Ultimate Solar Energy Course for Beginners

1. Solar Energy Course Content: Hi, and welcome everyone to our course for solar energy. I am Mathematics and Electrical Power Engineer. And in this course, I'm going to teach you everything you need to know about with solar energy systems. In this course. In the end of this course, you will be able to design that different PV systems from scratch and you can now work as a solar engineers. So let's start by learning what are we going to get from this course? So first, we are going to learn about the basics of solar energy systems. We will first understand how does solar panel work? How does it convert sunlight into electrical energy? And what are the different types of panels? And we are going to discuss some important factors when we are installing our PV panels. Then we are going to discuss the different types of charge controllers which are used to regulate that charging the batteries in the PV system. Then we are going to discuss more about the different types of batteries and the maintenance of batteries and charging of the battery. Then we are going to discuss different types of Xa inhibitors which are used to convert that DC voltage or DC power into AC voltage required in our facility or in our home. Then in the next part of the course, we will learn how can we design zack off-grid system or as a stand alone system? And how can we design our own grid system? What I mean by a design? How can we select panels, the inverters, charge controllers to form a complete BV system. We are also going to discuss is that design using an important program called the BV program. Then we are going to discuss another important system, which is a solar water pumping system. We will understand how can we use solar energy and water and plumbing systems and how can we design them for irrigation? Also, we are going to discuss is our prediction of BV system. How can we protect our BV system against the over voltage or short-circuit levels. And how can we select is that fuses and circuit breakers inside our PV system. Then we are going to discuss design of that grounding or the LCME system. So how can you form n or sink, grant or add grounding grid in order to protect humans and our electrical equipment. Also, we are going to discuss how can we simulate that PV systems in both the ITA program and the MATLAB programs. Finally, you will find inside our course and complete course about ITA program, which is an important program which is used in that simulation of the electrical power system. You'll learn about Beaver system, wind energy, and other types of BEV system or other types of power systems that can be simulated in this program. So in the end, this course is pretty, pretty important for anyone who would like to learn about BB systems design from scratch without any previous knowledge. Even if you are an electrical student, electrical engineer, mechanical engineer, or a mechanical student, hold like to start working in the renewable energy sector. So this course is for all of these people, and you will find that the content of this course is not found on any other course. Okay? So I hope you join me in our course and if you have any questions, just send me a message. Thank you and see you in our course for solar energy. 2. Introduction to PV System: Hi, and welcome everyone to our course for solar energy. This lesson, or in this section, we are going to discuss some basic concepts of solar energy. So first, we have a typical PV system, as you can see in this figure. This representing a BV system, which is used to provide electrical power to our house, e.g. so we have several components in this figure. First, we have the solar panels. Solar panels are used to convert zack solar energy or the energy from the sun into electrical energy. So this solar panels produce DC power. That is the first component of our system. Second component is that we will have the solar a charge controller. This regulates the charging voltage of the battery. Now, as you can see in the system, we have solar panels is that producers electrical energy. And do we have here batteries? What is the function of batteries? Batteries are used to provide electrical power at night or when the sun is not available. So in order to charge is this batteries, we need our charge controller that is responsible for a charging the battery. So we have here DC voltage. Now, as you know that in our house, we use what? We use a C voltage. So as you can see, the power coming from zap batteries. All that solar panels is D, C power. And in our house we need AC power. So in order to convert from DC to AC, we need the inverter. The inverter converts a DC voltage into AC voltage required for operating our house. Okay? So as you can see in this figure, is this representing our complete BV system or to be more specific and off grid PV system. So we have how many components we have the solar panels, we have such controllers. We have batteries, and we have the inverter, 123.4. So we will start discussing in this lesson that solar panels. And then in the next lessons, we will discuss the rest of all of these components. So before we started discussing the solar panels, we need to know why should we use solar energy. And instead of something like wind energy or wave energy? First it provides is green energy. It does not consume or providers C02. Second advantage is that it is free and available all of the time. Or to be more specific, to be more specific in all of the regions of the world. It can be used, can be used locally, which means it reduces losses. What does this mean? It means that I can install it on my own house or diastole and to provide electrical power to my own house. Force. Advantages that it is the operation and maintenance costs of BV system is very low because all you have to do, or usually what you have to do is that you need to clean the solar panels every now and then. Also it is silent. It means it does not have any noise because it does not have any mechanical parts. As you can see, it has no mechanical parts. It does not move. It does not have any mechanical parties like e.g. wind wind turbines. You know that when the turbines they are rotating and all contain mechanical power parties, which means it affect us for this end, any flying objects. And of course, it is very easy to install solar energy. And this is also used in the spacecraft applications, such as satellites or any missions to Mars, e.g. it needs, or it is operating using solar energy. Now, what are the different disadvantages of using solar energy? Number one, no power at night or during cloudy or rainy weather. So e.g. at night, there is no sun. It means there will be no power coming from solar panels. And that's why we need battery in order to be charged by Czar solar panels to provide electrical power at night. However, you have to know that batteries are the most, batteries are the most expensive part of the whole PV system. It is a primary cause of the high cost of alpha bb systems in general. So it is the highest or the most expensive components of all of these system. So this representing a disadvantage of using solar energy. Another thing, it requires additional equipment such as inverters and patterns. It has a low efficiency, 15-18% usually will find that mono crystalline, as we will see in this video. Type of PV panels, called the mono crystalline. It has an efficiency. In the market you will find about 18%. So it is very low efficiency, okay? It just absorb is 15-18% of the energy of the sun falling on it. So it is in general, low efficiency or low conversion of electric energy of the solar, solar energy into electrical energy. Compared to other types of renewable energy such as wave energy and wind energy. And of course, it needs a continuous cleaning. And for high power, bb requires a large area which is difficult to obtain insights. It's okay. So depending on the space, on your own roof here will have you will get a certain amount of power. And to produce a gigawatt projects, e.g. you will need a large number of panels are large area. Okay? So first, let's discuss the construction and principle of operation of a PV panel. So first, this is a BV panel, as you can see here. Now, this beaver panel, as you can see, it is used to convert the energy of the light or solar energy into electrical energy by an effect called the photovoltaic effect. Okay. So before we go to this slide, let's get back here. You will find that this is our panel, okay? Which is the one which is available in market. We use several panels. We connect them in series and parallel in order to achieve a certain current or a certain voltage. You can see that this panel is formed of cells B visa. You can see this block is called the acyl. This block is called a cell and another cell and so on. So we have BV panels, different types of BV balance according to the type of the vessels, as we will see in this lesson. So let's see what is the construction of a BV panel. So ABVD panel, as you can see here, consisting of all of these components, we have a frame which is used to mount the solar panels during installation. We have that last panel here, which is used to protect his or solar cells here from damage. Then we have here two layers here. These two layers are used to protect or holds it holds in position and prevented some moisture and dirt from reaching this cells. Okay. Then we have the junction box which is used the two connectors are other PV panels with it or it is used to give us the two terminals of this palette. We will discuss it in details, don't worry in the next lessons. Okay? So here is, this is a main construction of a PV panel. Now you can see that here. Let's look carefully about this. You will see that we have cells, the solar cells. Okay? So we have each solar panel like this one, like this one or like this one, consisting of a building unit called salary. Each cell is used to convert solar energy into electrical energy. Then each panel, or sometimes we call it module, can be connected in series and parallel to form something which is called array. Now why do we connect PV panels in series and parallel in order to increase the total voltage and total current. Don't worry, we will discuss this also in the next lesson. Okay. So what do we need to know is that how does the BBC will convert sunlight or solar energy? Into electrical energy. So if we take just one cell, this graph representing one cell, okay? Now you can see there is a first, the first layer here we have our coating layer or an anti reflective ray. Anti reflective layer. This prevent is a reflection of sunlight and allow with all of the sun or most of the sunlight to pass through it and reaches that solar cell, or the inner solar cell. Okay? Now we will find that we have conductors, semiconductors here. This conductor and this conductor is used to give us the two terminals of a cell to them as positive and the negative. You know that any, any battery, e.g. like this, a battery has a positive and a negative terminal. So we have here a metal part and metal layer for the negative or positive and the other layer for as a positive or negative. So we will have a boast of terminal and the negative terminal so that when we connect an electrical pulp or any load, we will have current going from positive to salute, such as our ball, e.g. all blah exists and getting back to the nicht, okay? Now the most important part of this B cell is that b n junction. This part B in the junction is a, junction is one which is responsible for the conversion of solar energy into electrical energy. Funds that each photovoltaic, photo, photo voltaic cell is basically a sandwich made up of two slides of semiconducting material. Photovoltaic cells are usually made of silicon. The same materials in microelectronics. To get this field or to get an electric field, the manufacturers use or dope silicon with other materials, giving each a slice of sandwich, Apple stuff, or a negative electric charge. So the add phosphorus to the top layer of silicon, which add this adds an extra electrons giving with a negative charge to that layer. And another one, we add boron, which gives us our bolstered by charge. This will lead to the presence of an electric field at the junction between the acetylcholine. So what does this even mean? All of this. Okay. Don't make this easier for you. You have to know that first, the photovoltaic are usually made of silicone. So we have two layers. Layer like this and another layer like this. Okay? This layer, and this layer is formed of silicone. Form it off. Okay? Now with that top layer, we add to it. We inject inside it, we inject phosphorus atoms. Phosphorus atom. Now phosphorous start is making a bond is with this circle. So when we inject phosphorus here in the silicon itself, it will start forming bonds with silicone. And you will find that we will have extra free electrons. So we will have here in this layer extra electrons. This is due to the composition of the phosphorus itself. So we'll have negative electrons, excess number of electrons. Now when we add or inject boron to the second layer, you will find that we will have extra holes, the holes, the goal eight holes, or both the rituals or bolster volts. So we will have in the end layer, the top layer called the Zak, n type layer, n-type silicon with negative charges and a bottom one, which is called the p type or full of charges. Now, this due to the presence of larger number of positive holes or fewer and fewer electrons, then you will have what is called the ZAB be in function since we have a B type silicon and n-type silicon. So this combined with each other forming that be n junction. So how did we achieve this and this by adding here phosphorous and by adding in boron. Due to the chemical reaction itself, we would have excess electrons which are not connected to any atoms. And we will have here excess positive holes which are not connected to any atom. So let's see this in animation so that we can understand the idea. So we have first the B type material. We have the n type material. So we have B type material which has, as we said before, has large number of moles of ions or not positive ions to be more specific holes, we have large number of holes. And the endothelium, which has excess number of electrons, are large number of electrons. Now when we add these two layers together like this, what will happen in this case? You will find that here, that since we have here holds and we have here electrons, okay? So we have here holds and that we have or boast of holes and we have negative electrons. So what will happen in this case? The electrons will start to go into from here and the fall, this holds. The electron wanted to fill these holes like this. So when this electrons leave this part and go and fill this holds, what will happen in this case? We will have here a positive ions, okay? Since this electrons of goals here, we will have negative ions. Will find that we will have in the end our positive ion. And the negative ion, which will form something which is called the depletion region, which is between, which has a positive ions and negative ions, as you can see here, due to the chemical reactions between this part here. Okay. So as you can see, we will have be an injunction. Moles of ions, negative ions in an electric field will be formed it going from positive to negative, like this. Okay? Okay. So here, this electric field will help us understand what happens exactly. Okay? So let's look at this image. Okay? So you will see that here we have the n type material, we have the P-type material. And then we, when we connect them together, when we bought them above each other, you will find that the phenomena will happen. Okay? The electrons, here we have excess number of electrons, negative, negative, negative. And then we have here excess number of folds at this point, at this intersection point. Now is that electrons will go and fill this holds, leaving behind it boast of ions, leaving by 10 mol of ions. And here will be negative ions. Okay? Now this is when, then this is at normal state without any photon, so without any light, without anything, just by adding an nn0 type over a B type silicon layers. Now we will find that here what will happen when light comes here and fall on this region or on the depletion region. So when light will fall on the depletion region, what will happen in this case? The electrons will have enough energy. So when a photon or sun-like Knox and electron free, it gives it enough energy to leave that atom. Okay, the electric field itself full bush, that electron out of silicon junction. We'll see that here when the light falls here, we have a free electron and we have a three balls, the balls, okay? Now you can see we have a magnetic field, the magnetic electric field here, from positive ions to negative volumes. Okay? So what will happen is that the negative electrons will be affected by the electric field. And the goals to zap layers or the location of supposed of sign ends up bolster holds. We'll go to the negative ions. So we'll find that in the end. You will find that the electrons will go to the upper layer, which is the n type layer, and holds the whole here we'll go to the lower layer. So what will happen when we have lots of light falling, lots of light. So we'll find is that when we have large, large amount of photons, electrons will have enough energy and we will have larger number of holes. So this holds. We'll go here and electrons will go here. So in this inner thigh, we wouldn't have large number of electrons. And the fourth is a p type. We will have large number of holes. Okay, So there will be large potential difference between these two layers. Okay? So what, what if we connect this part or the n type with a load such as a pole, and then connect it to the other layer here. What will happen inducing here we have large holes, large number of faults, and here we have large number of negative electrons. So these electrons would like to go and they fill these holes. So they will go through the wire like this and go fill this hole. Second electron will go and fill this hole. Electron goes and fill this hole. So what will happen when we have a flow of electrons? Flow of electrons is means is that we will have electrical current or electric cars. Okay, so I hope these ideas clear assembly when we have electrons, when we have energy, then due to the presence of magnetic, due to the presence of electric field, electrons will accumulate on the n type silicon layer, and the holes will accumulate on the p-type silicon layer. So we will have here large number of holes. We have here large number of electrons. When we connect this two layers together, electrons will go to the holes. Go to the holes. Why does the electron would like to go to the holes? Because it would like to be in a balanced state or would like to be in a neutral state. Every sink in Mitchell would like to be in neutral state. Okay? So this is how walks, okay? Now if you look at each cell here, you will find that each cell, this one, this cell look like this. K or each block like this of the PV panel will look like this. This sort of presenting oneself. You will find that we will have this lines, this lines, this lines, what does this represent called the fingers. And we will have two big lines called Zappos bars. So that fingers or the bus bars as opposed spouse first are used to conduct DC power generated by cell when photons header cells. So we see all the wires that connect each cell to the other one allowing the current to flow. So as you can see here In this, where exactly here. If you look here, don't worry, we will see this in the next slide. You can see this is the cell. Have a line here which has a past bar and Amazon. Okay. You can see it's an extra cell, it's connected to it in series like this. Connector exists and the next one connected like this, and like this, like this, like this. So when this as a current will go through all of these passports. So they are connected in series and parallel, as we'll see. 3. Types of Busbars and Solar Cells: So what does a function of fingers? So the fingers collected a decision rated current, DC currents, which is the electrons. You can see that we have large number of free electrons. So how can we collect this? We collect them using the fingers, collected all of the negative electrons, free electrons generated by the sunlight. And it delivers them to the bus bar, deliver them to the Pulse bars. Then we will have a bus bar itself, which have large number of electrons, will be connected with other passports to increase the total output voltage of the panel. Funds that each one cell, each block of this one is has a voltage between generics volts between 0.5 and 0.29 volt. So when we connect these panels, these panels in this cells in series, we will be able to increase the total voltage. And the cells are connected in baritone, creates the total current. So how can we achieve this by using some sandwiches calls that tire players and wires. So if you look at here we have one cell, here's another cell, another cell. You can see we have this bus bars plus bar and on a surplus bar and also plus one. Now you can see this one and this one and this one. Now, this one generate, let's say 0.5 volt. And this one generates a 0.5 volt, and this one generates 0.5 v. So when we connect, connect them together like this, connected them together like this. You will find that the total voltage, since the audit in theaters wouldn't be 1.5 volt. So we increase the total voltage of Pi connecting them together in series. So how can we achieve this by using that tab wires? You can see is this wire, this wire that can connect us between these two cells. This wire is called setTab wire. This wire tap wire, and as our top wire connected the cells together. Okay? Okay. Now, as you can see here, so the top wire can be added manually or automatically to the solar cell passport, which connect the individual cells in series with a low series resistance. Now what does the function of bus wire? So we have here this plus wire, as this is the top wire and this larger bus bar, you can see it connect this souls in parallel. Now, how is this happening? If you look at here, you will find that as this one have a current, let's say 0.5. And this cell also provides 0.5 there. This 1.5 and here, okay? So this bus bar connect us all of this parallel, which means that the total current inside the bus bar I from the nodal analysis, it will be 1.5 ampere. So the clusters of type words, strings are connected in parallel by using the bus wires, which delivers that cumulative current from all the cell to the BV junction box. Remember that WE junction box is the final two terminals is a final poll step and the final negative of the PV panel itself. Don't worry, you will see this in the next lessons. Okay? So what you will learn from here, you will learn that bus bars are connected in series to increase the total voltage. We connect them in parallel to increase the total current. Okay? Now, the bus connected in parallel by using paths, wires connected in series by using tab. Now we have also different types of spores. So if you look at this panel e.g. you will find that 12.3 plus bars. However, you will find another panel, 123455 lines, or five plus bars. So what is the difference? You will find that we have two plus three plus four plus five plus four different configurations for bv, which one is the best? So first, the three passport, it is the most common solar cell design. Or the most common solar cell design involves a three-part, uses a 3 bar bars printed onto onto the cell. Also we have the five bus bar, which is that trend, the trend. And you will find that the higher the number of passports, the petal. Now why is this? Because the high number of passports reduces the distance between the bus bars, which reduces their internal resistance loss. You can see that electrons would like to travel and go to this one, travel and the go-tos, the other one. However, if we look at here, we have a smaller distance. Here we have a very small distance. So smaller distance or smaller finger. It means that we will have a smaller internal resistance. Which means that according to Ohm's Law, we will have larger number, larger amount of current. So the high number of bus bars, it reduces the finger lens, which means the finger resistance will be reduced. So additional Pulse bars create lower resistance between salt. So you can see here more passports or you can think about it that Parallel, Parallel Branches, more parallel branches wins. The total resistance is lower. Okay? You can think about it like it's very small distance. And here we have large resistance. Okay? So if this resistance is all, Let's say e.g. all over five, smaller resistance, smaller electrical losses. So as you can see, according to Ohm's Law, that as a resistance goes down, the current will go up for the same voltage. Which means that the total power generated from the panel will increase because power equal to VI. So when we have larger number of passports, it means that we will have lower resistance or higher electrical current, or electric, higher electric current, which means higher current, higher generated. Okay. Okay. So you will find that the result of the additional passport is just solar ponds, or about two per cent more efficient than the one with lower amount of bus bars. Now, the question is, is to present, is really, really effective or not. You will find that the 2% is really effective compared to solar panels. Now why is this? Now we will find that we have different types of BB salts. We have the mono crystalline silicon solar panels that we have a polycrystalline or multi crystalline solar panels. We have the amorphous or thin film solar panels, and then we have the hybrid silicon solar panels. Different types of finance, which uses different type of beef cells. So in order to understand if this to present a really effective or not, you will find, we will need to understand this four types. The first type, which is called czar, mono crystalline silicone solar panel. This is a figure representing one panel which is format of a cell like z, which is this one called monocrystalline cell. Now what does this mean? You will find that this panel is one of the most effective solar panels, not the most effective, but it is one of the most effective or the one which is available in the market. It has an efficiency 15-24%. They are cut out from a single source of self-concepts. Why they are called Mono. Mono means one or single. That's why monocrystalline means that it is cut out from a single source of silica. They require less space than other types of PV panels because they produce more energy and can produce up to four times more power than the sun. Solar panels, which we will discuss. They also lost longer and perform better at low light. The only disadvantage of this one is the cost, which means it is not the first choice for the homeowners. Okay? So you have to understand higher efficiency means it will need number of one and z required to achieve a certain power will be reduced. However, low efficiency, low efficiency means that we will need a higher number of panels to achieve the same function. So higher efficiency means that we will have high cost. Okay? Also this type of finance is affected by dirt or shade which can break the circuit as we will learn about awards, that shading effect, that shading effect that we will learn about it in the course. And you will understand how it affects us, our PV panels. The second type is called the poly crystalline or multi crystalline solar panels. You can see this is a A multi crystalline panel. You can see it's really, really dirty type of solar panels. You can see not like this one if you look at this one, really clean and beautiful solar panel, compared to this one, you can find them panel, okay. Why is this? Because you will find that it has a low efficiency, 13-16%. And polycrystalline are often seen as a better economic choice because they are much cheaper than the monocrystalline. Here, y, z are called polycrystalline because they are made of several types of silicon which are melted together and then recrystallized. However, the zone monocrystalline has its format of one single type of silicon. However, is a polycrystalline. Several types of silicones are melted together and form this weird chain. Okay? The only problem of polycrystalline, it has lower efficiency, which means that we will need large number of panels to achieve the same function. So here's a small comparison between monocrystalline and polycrystalline. So this is a polycrystalline and this is a mono crystalline. Okay. Now another type, which is called the amorphous or the sun solar panels, which is this one. This is called the sinful. And it can be installed in a, in areas in which that space it does not really matter. So it has an efficiency of 70%, very low efficiency. And it is considered as the least efficient on the market. But they are the cheapest option. They work well in low light, even when light. And they are made of a non crystalline silicon that can be transferred in some form into another material such as gloss. You can see here, we can add it in building like this. And it can be used to convert solar energy into electrical energy. However, it has a very low efficiency compared to the other types as ammonia or the polycrystalline. Mean advances that it can be mass produced at much cheaper cost, but it is more suitable for situations where the space is not a big issue. Another disadvantage of this one is also it is not generally used for is potential purposes. And the wealthy grade quicker than crystalline solids. So usually we don't use this in the residential application or in our home. Because, why? Because, why is this? Because it has a very low efficiency. Remember cent, which we will discuss is called the hybrid silicon solar panels. Okay, here's all. You will not find them in the market. Why? Because they have the highest or the best efficiency. The hybrid solar panels are made from a mix of amorphous and the monocrystalline cells to produce the maximum efficiency. Now they are, there are a variety of types of hybrid cells and they are still very much at the research and development stage, which y is they are currently are more expensive options. We don't use them general. Generally we don't use them. You'll find that one of the resources which I found is that in 2018, the hybrid silicon solar cell in resource. As I remember in Journal of Nature, energy, neutral energy. It reach, it asserts three points, 3% conversion efficiency, very high efficiency, the highest recorded efficiency. And of course it is still in the laboratory stage. It is not in the market. Okay? However, it's considered as one of the best of times and it has a very important efficiency which can help us help reduce that, reduced the amount of panels required. Okay, so in this lesson, we discussed an introduction to solar energy. We discussed the different components of solar energy system. We discussed the construction of PV panel and how a solar cell walks. And we discussed the different types of solar cells. 4. V-I Characteristics of a PV Panel: Hi and welcome everyone to this lesson in our course for solar energy. In this lesson, we will discuss more about solar panels. So first, you will have to know that any panel, any solar panel, it has two terminals coming from it. One which is a positive terminal, and the one which is a negative ten. Okay? So when you connect to any of these, these two e.g. or Paul border resistor, then a current will flow from positive going into the negative terminal. So this can be considered as a voltage source, like a battery, okay? Okay. So now you can see this is a junction box in which we will have the two terminals as opposed to enter negative. Now what we would like to do is that we would like to find the VI characteristics of a solar panel. Or VI means voltage, current characteristics of a solar panel. I would like to see how does the voltage and the current looks alike from the panel. Okay? So first, as you can see in this figure, here, shows you the voltage on the x-axis. We have the voltage on the y-axis. We have the current guarantee in ampere and voltage of the panel. So this is the output voltage from the panel. This is the outward current from the panel. Okay? So let's start First. We have two different tests that we do. One which is called the open circuit test and the short circuit test. So what does this mean? Open circuit test is that we will leave this two wires opened. Suppose that the negative terminal is open circuit like this. Okay? Then we start adding an voltmeter. Voltmeter, which measures the volt meter, which measures the voltage here. This voltage is known as the open circuit voltage, okay? Or V open circuit. You can see V open circuit or the open-circuit voltage. As you can see, since this socket is opened, it means that the voltage will be equal to V. Open circuit, the open-circuit voltage and the current, what is the value of current? Current will be equal to zero because the circuit is opened. So we'll find that the first point here we have the voltage V open circuit, and the corresponding value of current is zero. This is the first point here. V open circuit at which is a current will be equal to z. Then the second test is that we will make a short circuit test. So we will do like this, connect these two wires together, the positive and the negative together like this. So what do you think is a voltage will be here between these two terminals. The voltage will be equal to zero. Why? Because we have a short circuit between these two wires, between the ball step and now in this case we would have maximum current. Current will be maximum will be the highest value. And in this case, we say that that current itself is equal to I short circuit or the short-circuit current. So the voltage is equal to zero here, and the current will be short circuit here. We have the first point, second point on the graph, and the first point on the graph here. Now between these two points, I would like to find different values of current and different values of voltage. So how can we do this assembly? We, we connect as a panel. We have a panel like this. We have the positive and we have the negative. And then we start connecting it to a variable resistor. Variable resistor like this. By changing the resistance, we can obtain different values of voltage and the current. So we can draw, finally, this curve. As you can see, this curve is called the VI, characteristics of a solar panel. Okay? Now similar since we obtain the current and voltage. So at any instant, let's say e.g. this voltage V1, we have the current which will be produced, will be current one. Okay? So the next thing we would like to do is that we need to find the output power of a panel. You know that the power in general is equal to V0. The blue bar is the current or the voltage multiplied by the current at any point, at any point, let's say here we have V1 and we have current one. So that corresponding power here will be this point which is B equal to V1, I1. Here at this point we have a voltage equal to zero and the current equal to I short circuit. So their multiplication will give us zero and so on. So you do this for different values of current and voltages like this and in z and you will obtain this graph, which is called the power characteristics of a solar panel or as a power curve of a solar panel. Now, as you can see, is that this curve has a certain value at which we will have maximum power. You can see is this point, which is the peak power, maximum bar p maximum occurs at a certain value of voltage called the V m and a certain value of current to call the RAM. So B M, which is the peak power coming from subpoena, is equal to i m, multiply it by v. So this v m is less than our open circuit voltage and i m is less than, or it short-circuits. Okay? It is between zero and I short-circuit, and this one between zero and V open circuit. Now, this point at which we will get maximum power is a value of voltage and the current is called the maximum power point MAP p, or the maximum power point. It is the point at which we will get the maximum power point on the VI curve at which we will have a certain value of voltage and certain value of current that will give us the maximum power. Now why is this important? Because we are going to control or use buck converter or we are going to use a solar charger controller in order to control the output voltage of the solar panel. So that we can always get the maximum power as we go, as we will see in the maximum power point tracking glass ones. Okay? Okay. Now the question is, how can I know, how can I know the operating point of a solar panel? Now e.g. you have this solar cell, some very small solar panel or a solar cell connect, connected to Paul, e.g. you can see we have the positive terminal as black is the ground. And then we have the orange one, which is a poster and the black is negative. Then we start connecting it here like this, and connecting like this. So we connected our panel to allude or the palm. Now the question is, what is the output voltage and output current of the panel in this case. Okay. So I would like to know what is voltage and what is Karen, how can I get this assembly? You will find that this is a characteristics is a blue line representing the characteristics of the BV Banner. As you can see here. Now in order to find the operating point assembly, we draw a line which are representing Zach characteristics of solute. You can see this is our polymer, which can be representing via resistance. So resistance equal to V over I, which is the slope of the line here, assuming that the resistance is a constant value. So we will have connecting it like this, drawing it like this. Okay? So the intersection between Zach characteristics of the load and the characteristics of the PV panel, their intersection, which at this point will give us the corresponding voltage and current. So as you can see at this point, we will have this voltage and we will have this current here, e.g. corresponding value of current. How did we get this by simply intersecting the characteristics of the load with the PV panel characteristics. So the PV panel characteristics that we obtained it by doing by connecting to a variable resistance or a variable resistor load. And then changing the value of that resistance. Then measuring the current and voltage. For the load itself, it has a characteristic. Some loads like this. Loads are like this, and so on. So they have different characteristics. So if it is e.g. like this, then this point will be the operating point. Now we would like to understand more about panels. So we will learn about the solar irradiance. So what does solar radiance mean? The solar irradiance, or S, is the power per unit area received from the sun in the form of electromagnetic radiation. And it is measured in watts per meter square. So as you know that if we have a panel like this, the sun falls on it. Okay? So the energy content, or let's say power dynasty content and sizes. Sun rays are called the solar irradiance or sometimes called the solar insulation. Solar irradiance or solar insulation. Okay? Now this raise or a radius is measured in watts per meter squared. As an example, we have a standard value which is 1,000. What bear meter squared. This is a standard values at which we will get the datasheet for this panel. Always the values given our according to this value of radians. Sometimes called the STC or standard conditions. This STC at 25 degree. And once I wasn't what they are, meter square radians. So e.g. if you look at this panel, you will find that this panel in the market, this is from Alibaba website. You will find that it is surrounded and 20 what? Polycrystalline solar panel. So that's zero hundred and 20. What? So on 20 or what solar panel. As you can see here, this value of power, which is the maximum power, it is obtained at a temperature of 25 Celsius degree and radians of 1,000 watt per meter squared. Okay? So according to the solar radiance, we can have a variable output power. So e.g. in order to understand how does panel convert this sunlight. So I would like to remind you of something which we have said before. So remember in the previous lesson, we said that the monocrystalline or polycrystalline have different efficiencies. Okay, the front efficiency, depending on the type of the panel. So as an example, this one is in czar market on Alibaba. In China. This panel has an efficiency of 18%. It team present efficiency. Okay? So it converted it in percent means it converters, Converters 18% of the radiance falling on it. And you will find here in this essential data details, you'll find here is that I mentioned of the palate. You will find the year Len sum multiplied by width, multiplied by the depth of the panel. This is in milli, milli meters, millimeter, 1,156 mm means it is 1.2956 multiplied by 0.992, multiplied by 0.0 for all of this means. So it means that the lens of the panel itself is 1.956 m and the width of the panel is 0.992. And the depths of the panel itself is how much? The depth is? 0.04 m. Okay? Okay. So here, this is a length, width, and depth. Now you will understand why is this important. The dimensions are important to understand the efficiency plot. So here we will find that this type of panels has different types inside it, or this model of panels has different types. So you can see it has from Silvana 22 360 p between two brackets, 72. What does 72 means? It means it is consisting of 72 cells. As you can see, a number of cells in one panel, 72. So as you can see, this number representing how many salts. Now Sarah, 120, 260. What does this mean? It's around 20 means how much? What is the peak power? To be more specific, what is the peak power? So, the peak power here. So first tomatoes on 22nd, 13 to five surrounded 1,340 upto 360. So we have different panels, 1234566 balance. Okay, so this is a big but maximum power that can be produced the pi sub panels at STC conditions or standard conditions, okay? At 1,000 watts per meter squared, the amount of power for each meter square is 1,000. Okay? Remember, you will find here is a maximum operating current. This is a maximum rating current. And the maximum operating volts. What does this mean? This two values are the values at which we will have that. What? The maximum power. Okay? So in order to get a big power, this, this peak power of 120, we need this value of voltage and this value of current. Okay? Now we have also the open circuit voltage, as we learned before, and the short-circuit current of the panel. And you will find that each one of these panels have an efficiency. Because Steve, 14,916.7, 17, and so on. This is the efficiency of conversion. Okay? Then we have finally the power tolerance from zero to plus 3%. What does this mean? It means that if e.g. this one has a peak power of 120 watts, the power tolerance, it means that not all the panels are the same. There may be a small error. This error, it means that 0-3% to plus three per cent. So it means that the power can be from here, 320. What, at zero tolerance up to row hundred and 20 plus 320 multiplied by 0.03, 0.0 stream point, or three. Very small present. Okay? So it means that if the panel is not exactly drawn to and it can be is 120 and up to 120 plus 3% of its value. Okay? Okay, so now let's just delete this part here. Okay? Like this. Now I would like to prove this point. So as you can see, this one, e.g. there's zero hundred and 41. This panel has an efficiency of, let's delete everything first, are all leaves them as it is now. We have a zero hundred and four to one, okay? This is a big power which occurs, adds up conditions of one cell wasn't watts per meter squared. Right? Okay. And the modal model efficiency is 17.52%. Okay? So I would like to prove that this panel is actually so hundred 40. How can I do this assembly? You have the efficiency, efficiency of converting this power and this power. Okay? So when you multiply one watt per meter square, which is some ray is falling power on the pattern. If you multiply one cells antibodies as 17%, you will get how much, what Bill meter squared our panel will convert into electrical energy. So as you can see, if we take the 1,000 watt per meter squared, multiplied it by say efficiency 0.17, 52, we will get 10,775.2 watts per meter squared. So the panel itself converted from the sunlight one-thousand what? The sunlight convert it to 175.28 absorbed, absorbed bit 17% or 1,075,275.2 watt per meter squared. Okay? Now remember, this is what per meter square. There is another factor. You have to know, the power here. What is the unit of power? Power is in? What? I need to convert watts per meter squared into what. How can I do this by multiplying by the area. What area, area of this panel. You can see the area is equal to lens multiplied by width. So we have 0.992 multiplied by 1.956, like this. So we have this power multiplied it by the area. So you will have 3,319.2941. Now, if you combine this value which we obtained at a similar tools or 341, okay? So I hope that idea of the efficiency is clear for you now. Okay? Now I would like to see what is the effect of z installation or the irradiance on the VI curve, I would like to see what is the effect of radians itself. Or how many watts per meter squared on the V icon. You'll find that, as we said before, solar radiance power per unit area. So the forms the sun and measured in watts per meter squared. Now, if we look at this curve here, you will find that, let's say we started at this graph. This is a value of current. And this is the value of voltage at a constant temperature. Here is a parameter which we change is the regions. How many watts per meter squared? So this is a panel characteristics. When we have a 250 watts per meter squared, okay? Energy or the power density coming from the sun. Now, as you increase regions, as you increase the regions, 250-500 to 751,000. As you can see, as we increase, what will happen to the curve. You can see it's going up. So you can see that the value of current here, instead of here, it increased the two here, increase the two here, increased weight. So as radians increases, the value of current increase, increase. In this case, when we are keeping the load constant, okay, we are just changing the radians. Now what about the voltage? You can see is a voltage as the radius increases. You can see a voltage increased by a very small value. So what we'll learn here is that as the irradiance increases, the current increases by a very large value and the voltage increases by a small way. So what is the effect? What is the effect of this on the power? You can see this is our power at a 400 watts, 600 hundred and 1,000. As you can see, as the radius increases, 400-1 thousand, you can see that the power increase. You can see this is a peak power increased to much higher of x. So what is the effect of radians? It increases the current, increases the voltage, and in the end it will increase the total power. Okay? Now we would like also to see what is the effect of temperature on the I-V curve. You'll find that as the temperature increases, what happens to the system? So as the temperature increases, you will find something which is really, really interesting. As the temperature increases, the current increases. You can see this is a forest temperature at zero Celsius degree, zero Celsius degree. And second curve at 25 degree. And so the curve at 50. So logistically, so as the temperature increases, the current increases, you can see increases. But by how much? Very small value, very small increase in time. Okay. But what about the voltage? When the temperature increases, the voltage decreases or reduces? The voltage is increasing in temperature, reduces the voltage. So as you can see, we were at zero Celsius degree, 25 cities as degree, and 50 synergistically. So as you can see, voltage starts to decay hint. So what will happen here? You will see that current, when temperature increases, the current, current will increase by a very small value. However, the voltage will decrease by a very large value. So in the end, the power is equal to voltage multiplied by current. Voltage decreases by a large vein, gotten increased by a small vein. So in the end, the power will decrease. Okay? So what is the effect of temperature? Temperature will decrease the output power. Okay? Similar to here, you can see that they cannot increase by a very small value, very, very small value as the temperature increase. However, the voltage decreases too much when the temperature increase. So in the end is that temperature is a bad thing for us. Okay? Now if we look at power characteristics here at zero Celsius degree, very small temperature, and here at 75 cities vertically, you can see that the power curve goes down. Okay? So as radians is an important factor or installation important factor, that will produce more power. However, the temperature is a bad thing for us because it decreases the output power. Okay? So in this lesson, we discuss more about solar panels. We discussed the VI, characteristics. We discussed this opera is a effect of temperature and radians. And we understand more about the data sheet of the solar panel. Okay? 5. Different Connections of Solar Panels: Hi, and welcome everyone. In this lesson or in the previous lesson, we discussed one BB panel. We said that each BV Bannon, each panel produces at certain voltage and certain current. Now, how do we connect these panels? So we need to understand, are we going to connect them in series? All are going to connect them in parallel. And what is the effect of this on the output voltage and current? So first, before we discuss the panel, so we will understand forest, the connection of batteries or the connection of different voltage sources. It is the same idea as panels. So here as you can see, we have 12 volt, this is a pottery and another battery. And the somas are battery and the battery. Now what's the difference here? You will find that these two batteries are connected in parallel. These two pathways are connected in series. You can see the red terminal is in supportive, as you can see here. And the black terminal is a negative or connected to the ground. And we have here positive, negative, positive, negative. Now as you can see here, that the first one, these batteries are connected embarrassed because a negative connected with negative and positive connected was positive. So these batteries, each battery is a 12-volt and the 500 CA or something which is called the cranking and bear. Okay. Which are presenting worth 500 cranking and Bell representing 500 CA e.g. it means that this battery can provide 500 and bears for 30 s. Okay. Usually we don't use in our PV system, we don't use that cranking and bear. We use the unfair our bare hour or how many amperes or does our battery provide for 1 h. Okay? Okay. So here, this configuration, we can say each battery can be considered as a voltage source, a DC voltage source. So we have the first battery like this, positive, negative, and second battery like this. Okay, pause the negative. Now you can see that the negative terminal is connected with a negative terminal. So it will be like this. And the positive terminal is connected with the other pole stiff Turner. So we will be like this. Then the final output, which will be this terminal. And this terminal will be connected to any load, e.g. a. Resistance. So what will happen here? You can see here we have a 12-volt, another 12 volt. This battery will provide a current, all your one. And this pattern will provide the current i2. So what does the voltage across the resistors? Since as you are all embarrassed, so the output voltage would be 12 volt. And what is the total current going into the road? That total current is the summation of these two currents are u1 plus I2. So in this case you can see is that well the world 500 cranking out there and another 12 volt 500 cranking and bear these two connected in parallel. It gives us our final output voltage over 12-volt, similar voltage. But as a summation of the two currents. One cells anti cranking out there. Okay? So when we connect the batteries in parallel, we increase the total or the total ampere. Okay? Now let's see the second configuration here, which is a series configuration. You can see we have a bolstered negative, positive, negative. So we will have like this battery like this. Also negative. Okay. Now you can see that. Let's see e.g. the first battery can see here positive, negative, positive, negative. You can see that the bowl stuff connected to the negative. So if we add another battery like this negative and post them, you can see Falstaff connected with negative. You can see bolster connected with negative. And as our final positive terminal and falling and negative terminal are going to look like this. Okay? So what will happen here? You can see that the current coming from first, first battery is equal to the current going out from second battery. So the total current is also the same current. So if this one I, this also will be I ends the current going to the root is high. However, you will find that the voltage across the load here is from here to here, which is a summation of the 12-volt and another 12 volt. So the total voltage across the load is 24 volt. So as you can see that to 12 volt series with another 12 volt battery, that will give us 24 volt is the summation of the two voltages and the current will be the same. You can see same current flowing inside our circuit. So it will be 500, similar to the two patterns. So what did we learn? What do we learn from this? We learn is that when we connect as our batteries in parallel, we increase the total current. When we connect them in series, we increase the total voltage. Now why did we discuss this? Because it is a same idea in BV bundles. So as you can see here, the same idea for batteries. Again, we have plus minus, plus, minus two batteries, six of all, ten ampere hour, six volt ampere hour. Here you can see as they are connected in series. So in series they will have the same current, same current, and the voltage will be so summation, which is 12 over here. For the parallel, parallel connection, there is an outward current will be zero summation, which is ten ampere hour. And honors or ten ampere hour gives us 20 and Baroque and the voltage will be the same. Okay? Now, similarly therefore panels, as you can see here, we have two connections of planets. We have connected in series. They have panels, ones panels are connected in series. They form something which we call string, the string of panels or string of modules. It means that we have group of panels connected in series. Why is this to increase the total output voltage? And when we have a strings which we connected in parallel, we form an array. This array would increase the total current. So as you can see here in this example, this panel, e.g. reduce six volt and three and bear at any condition. In general. This one produced six volt and three and bear, or we can say e.g. this values are the values at peak power as an example. So we have 6 v three and bear 6 v 3.6 of all the three and bear. Now you can see that each panel has both positive and negative. Positive, negative, positive, negative. Now when this panel's, when negative connected was positive, negative four is positive. It means that these panels are in series. So since they are in series, then the output current will be the same three and same current. But the voltage will be the summation, six plus six plus six, which is 18 volt. Okay? So when we connect the balance in series, we form a string to increase the total voltage. Here, the same idea, you can see it well, volt five Umberto Volta five umber, and so on. When they are connected in series, you can see a positive was negative or positive was negative boast of different terminals when they are connected to each other, with each other, it means that we have a series connection. So you can see is our final output is same current and the voltage is a summation, 12, 12 plus 12 plus 12, which is 48 volt. Now, now we know you connect them in parallel. Here we have e.g. if we have this string, four panels or three panels, or any number of panels, you can see they are in series. So if this 12 volt and this one is two volt, then the total voltage is 4 v. So we have one string. Now if we connect, connect one string to another string. So if this panels produce one and bear e.g. Okay, This panels are produced one and then the parallel connection, which means that we have an array. It will give us the summation of two currents. It will be one plus one, which is two and bears. So as you can see, series connection or formation of a string, which is a series connection of panels, means that we are increasing the total voltage. Parallel connection of strings, or parallel connection of two strings or more. It means that we have an array and we will increase the total current. Okay? So I hope that already has clear. Why do we connect in series and parallel in order to increase total voltage and total current. Now, as you can see, e.g. this is a system for our BV, as this is a BV system. So we have forest as building unit, which is a fundamental bending unit, building unit, which is our cell, which we have discussed before, which was its own different types such as monocrystalline, polycrystalline and so on. We form, using each assault we form one molecule or one panel. Okay? Then we take this module or resist BV panel, connect them in series, as you can see in series. Let's say it's this positive, negative, as in this false negative, false negative. So we will increase the total voltage. Now, each string, like this 11 is string here, connected in parallel with another string connected in borrows another one, we will have a large array. Okay? So the module is formed of cells and the string format of modules in series or panels in series. And the array is full of strings in parallel. Now let's see what will happen if we connect BV panels or PV cells to the same RTT in series and in parallel. You can see we have 0.5, 0.5, 0.5, 0.5 volt. When we connect them in series, they have the same current. But the difference is that the total voltage will increase summation of the voltage. So as you can see here, e.g. you can see this is a one cell, e.g. one cell like this. This one cell have a maximum voltage of 0.6 volt and they have a current, let's say maximum current 2.8. And then now when we connect it with another circle with 0.6 volt and the point date. And there we have two cells. Here, you will find that we will have the same current, one cell, single-cell, and two cells. You will find here the current is the same, but the voltage is increased. You can see, let's say here 0.6, 0.6 volt. And the 0.6 volt summation gives us our 1.2. Okay? So you can see that when we increase number of cells, that voltage will increase. Okay? You can see shifted to the right. Okay? Here, this figure is a similar to this one. Okay? Now, when we have B vessels in parallel, what will happen is that the current, total current will increase. So if we have one cell like this single cell with open, with a short circuit current of 0.8. Then when we have two cells, the current will be doubled. 0.8 multiplied by two gives us 1.6. And the voltage here will be the same. You can see the voltage didn't shift. It is a same voltage, but the current is doubled. Now what if we have three cells and it will be like this, 2.4, which is 0.8 multiplied by three. If we have more cells like this, like this, it is a same voltage, but the current starts to increase as we increase the number of cells in parallel. So something which is important here, this figure, two cells in our notes here as parallel as the previous one here is a series. This one is okay. Now finally, if we combine all of this, what we will have, you can see that here. We have one. Okay? As an example, one solar panel with a certain current and certain voltage and short-circuit current, certain open circuit voltage. Now, if we add another panel in series, in series, in series, what will happen? The voltage will increase. So you can see the voltage shifted from here and the Became here. This is a new voltage. And the water pounds or current, current is the same. You can see this is a new all the current oldie curve. And this one is a new curve that I'm bear is the same. Okay? Okay. Now, what if we have the same curve here? And we added another panel in battery. Okay? So we have a panel here and we added another one in parallel so that total current will increase from here, becoming here, okay? And the voltage will remain as it is. Okay? Now of course you can combine these two together. So e.g. if you have partner likes us in series, then you add it. You have two panels in zeros like this. You have for me this curve, okay? If you connect those two panels in parallel to it, then this curve will be like this, okay? Because the increase, the total current. Now of course, in each case we have a maximum power point, maximum power point, this point at which we will have maximum output power at a certain voltage and certain kind. This curve has a maximum power point, which, at which or we wouldn't have maximum power. This is obtained by doing, by drawing the characteristics of the combined solar panels. Okay? So I hope that idea of series and parallel connection in PV panels as clear for you now. 6. Shading and Half Cut Cells: Hi and welcome everyone to this lesson. In this lesson we will discuss phenomena that occurs in BV salts, which is called the shading effect. And we also, we are going to discuss an important type of panels called as a half god sons. And you will understand what is the relation between shading and using the half god sells panels. So what is the shading effect in PV systems? So if you look here at this imagery, you will find that we have here our panels. However, due to the presence of Germany or a building or a tree, you will find that there is a shadow which appears on the solar panels. This shadow will lead to what? Lead to the reduction in the electrical power generated. Okay. So when I shadow is cast on a panel with our Y a tree, or on any other building or a Germany e.g. it will decrease the amount of electricity produced by a panel. Now, shading of just one cell in a module. One cell, one cell like this, which typically consisting of around 60 cells, can reduce some power I would froms abandon as much as 33%. You can see is that this shading effect is really, really harmful for our PV system. So how can we solve this problem? Okay? So we'll find something which is really, really interesting. You will find that we use something which is called the people's diets. It's a bypass diode. Bypass diodes. So bypass diodes are used to solve a problem of the shading effect. So as you can see, this is a normal operation when we have sunlight falling on our BV salts or PV panels. As you can see here. The current is flowing through all of these panels normally or cells normally. Now when we have a shading effect, like here, we have a shadow on this soul or this PV panel. You'll find that what will happen if we and allows air to pass through this cell. You will find that since all of these cells are in series, you will find that the total current flowing through these panels is very much, very much reduced. Okay? So in this case, how can I solve a problem like this? In this case, we use a czar by pass diets, some bypass diodes. What does it do? It bypasses or some, or a panel. As you can see, the current will flow like this. So this solves which does not have any shading effect. Then when it comes to this cell or the panel which have shadow on it, what will happen in this case? It is our current will flow through the diode or as our ApiPath night. Okay? So it will form a short circuit on the panel, okay? As if this panel does not exist. So the current will still be high. So by using Zap bypass diodes, we will be able to cancel any cell or any pattern which have a shading effect. So if you look at this image here, you will find that we have three times on shaded cell, partially shaded cell, and completely shaded. So you can see this on shaded cell which we have, which have all of the current solar energy. And it does not have any shading effect. So we'll have 100% of the current and voltage coming out from this side. Now, the partially shaded cell is directly proportional to the illuminated area of the cell. No voltage change. So the problem is in our current, you can see that that current is reduced due to the presence of shading on this cell. Now, for a completely shaded cell, we will not have any output zero current, zero voltage. So let's compare that in case. So if we have a bypass diode or if we don't have a bypass. So as you can see here, we have 1234 panels. We have four panels here or not four panels. We have how many panels? Ten panels. Okay. Ten panels. So we have here ten. Okay. Then one of them, one of these panels and we have one panel which has a shading effect. Shading effect, okay? Which one is this spanner? Ok, you can see that there is a shadow here, which means it has a shading effect. Okay? So sensors S1 has a shading effect that we have here, a bypass diode. So this bypass diode will make a short circuit on the panel. So as if this panel does not exist. So each panel here, a terminal here, has a voltage of 32.5 volt and the current date and when we cancel this one. So what does the output power, power number one is equal to how many panels are. We originally had ten panels and we canceled one panel. So we have nine panels multiplied by voltage of each pattern, which is 32.5 volt, which will not change multiplied by the current. Now since we canceled this panel, we will still have larger current, which is eight and bear as an example. So we will have a total power of 2,341. Okay? Now, in the second case here, when the pi bonds diet does not work, when the pulse by diet does not hold. So the power number to this panel which have shadow, will still be connected. We will assume that the bypass diode does not exist. So in this case we will have ten panels, total number of finances then because we didn't cancel this one, multiplied by ten, multiplied by, multiplied by the voltage, 72.5 volt multiplied by the current. So the current here in this case, since we have a one which have shading effect in series with all of this. So the current will be reduced so much, okay? It will be e.g. one ampere. So finds that the output power, in this case three to five. So you can see is that when we don't have a bypass diode, the total power coming from the balance will be reduced compared to the presence of bypass diode. Now why is this? Because the panel which have a shading effect, which has a shading effect, leads to a reduction inside our current. Okay? So by using a bypass diode, we can sum that shaded panel. We now have nine panels instead of ten panels, but with a higher operating current of eight and bear in case of weak keeping of giving Zack shaded panel, the number of panels would be higher or ten panels. But the current will be reduced a lot too one ampere due to shading effect. So that is the total power will be reduced. Combine the two, the white balance night case. So the solution for a solution for the shading effect is that by using the bypass diodes to cancel the panel which have, which has shading effect. Now, this will lead us to discuss another type of modules. This type of modules is really, really helpful and really becoming a trend. This type of panels called the half, half cut cell modules. So here you can see that we have the wholesale monocrystalline, crystalline, false or monocrystalline and the half-cell monocrystalline. So Zach crystalline here, as you can see, here, we have our panel behind here. We have the junction box that provide exam posted and negative terminal of the BEV battery. Okay. Now this this panel is monocrystalline type, which we have discussed before. Now instead of having one cell like this, one complete set like this, we are going to divide ourselves into half. So we will have half cut cells. You can see instead of one cell, we will divide it into two parts, two halves. We will cut it. So we will have half cells. So we will have another panel which is formed of half of the cell. You can see Hobson, half say convert to this one which is one big cell. Now why do we do this? What is the benefit of doing this? So here, as an example. This is an example to understand the benefit of having the half cut cells. Okay? So let's say we have here, we have here cells. This is a panel, and this is another panel. This one is a mono. Crystalline Type, and this one is the half cell panel. Now you can see that here in this panel we have three bypass diodes. So each path bypass diode will take a string of cells. So this bypass diode is used to bypass this string, a string of cells. And this bypass diode takes this part, the second two roles, or two columns, and this one will take the second two columns. Okay? So e.g. if we have a shading effect here, e.g. on this panel, then this bypass diode will start working. And the palaces, this string. So in this case, what will happen when we will lose one over third of our power? Okay? We will lose one over third of our power, our power. So we have here 60 sold and we will lose one of our three of the power because if we have a shading here, this pipe boss will work and they cancel this string. Now what if we have a half got cell? So I have capsule here, and instead of security we will have 120 because we divided each cell into two. Okay? Okay, so what will happen here? You will find that if you look at this figure compared to this one, and instead of having three strings, you can see here three strings as a string and this one, and this one. You will find that we will have six strings. We have 123. And since we are half, but you will find that we have four 5.6. And our ApiPath supplied will be installed here. And instead of an installed here. Okay? So if one of these strings have a problem or a shading effect, it will be we will lose one oversold of the power. However, in the second case, if e.g. we have a shading effect here only this part. What will happen is this bypass diode will cancel this part only. So we will still have 5/6 of our panelists. Or to be more specific, we are losing 1/6 of our power or 1/6 of our strings. You can see third of our hair, 1/6 of the power due to the use IT, usage of the half cut cells. So you can see that in the first case of T-cells monocrystalline, we lost the one over third of the power. Since our panel is divided into three strings, supplies a Pali, bypass diodes. Remember here's a string. What does this mean? String of cells, not string of panels. In the second case of the 120 half cut cells, we lost the only one of our sort of the power for each part, since we divided the panel and to six strings. So what are the different advantages of using the half gut cell? Number one, you will, as you know, that the power losses in any electric circuit is directly proportional to the square of the current multiplied by the resistance. As you know that electrical losses equal to current square multiplied by resistance, or be equal to I squared multiplied by R. Therefore, when cutting a solar cell in half, so power losses are reduced by a factor of four or by 75%. Now why is this? Because as you look at this figure, we have the full size and then we have the half gut size. So here when we divided our panel into or our cell into half, then it means that we will have here all over two half of the current here we will have on your work. So as you can see, we have here is the total current i then, which is this figure. Okay? So the original power losses, I square R and the half cancel. We divide it into two parts, half and another half. Okay? So in the second case, our power of each part is equal to e square multiplied by r multiplied by resistance. Now with the current itself is reduced by half, so it will be all over two. Since we have half of the cell. So it means that our power losses will be I square R divided by four, or it will be 0.25 of I squared R. So what does this mean? It means that our power losses is reduced the from hundred percent, 25%, or our power losses are reduced by a factor of four, which is 1/4, or by 75%. Instead of having 100 per cent, we reduced it to 25 per cent. This came from I squared R as we sit. Now Windsor area of solar is cut in half as amount of electrical current, as we said now, got by, each bus bar is reduced by half as well. As we said here. This decrease in the electrical resistance within the Pulse bars results in an overall increase in efficiency. Because as you can see here, and instead of having this long bus bar, we now divide it into half so the lens a smaller, so that resistance is smaller. So this will lead to an actual increase in the efficiency pair manufacturer, Whichever is in the range of between 1.5 to 3% efficiency increase. Now, as you can see, half cut cells here and the monocrystalline. Now what is happening in the market? If you look at the market in 2017, you will find that we have full cell technology, one big cell like this, 11 full cell. And we have another technology which is half cell, which are exhaust and discuss dividing it into two halves. And then we have another technology which I didn't to discuss, which is a quarter cell, which means 12.3. And for dividing a wholesale into four parts. Now as you can see in 2017 or 2017, you will find that most of the market, most of the panels in the market or folds are very large. And very small portion of the market is for the half-cell, and the quote itself does not exist. In 2018, you'll find that the market share for the half-cell increase a little bit. And ask volume pulses leading to 20 2018, we predict that it will be this part. You can see the quarter increased, ends off guard cell increased a lot because it is much better technology. So it is predicted that the market share for half cell will jump from five per cent in 2018. You can see here 5% to, up to 40% in 2028. Okay? So in this lesson, we discuss the shading effect in BV system. And we discussed the how to solve with this problem. And we also discussed the half cell technology. 7. Mounting and Tilt Angle of a PV Panel: Hi, and welcome everyone to this lesson in our course for solar energy. In this lesson, we will discuss mounting of BV panels or PV system and the tilt angle of a PV panel. So first, what is the mounting of PV system? Simply mounting means that we are installing our PV system in different ways. So we can install our PV system on the roof, e.g. such as in our home. Okay. Like this, this is a forest type of mountain called the roof mounting. We have all mounting on a pole here. As you can see, that we have ground mounting, which is used for large GBV systems or mega bps systems. Now the roof mount, you will find that it is simple and cheap to install because you are just installing PV panels on the roof itself. We don't have any flexibility in orientation of the PV system. What does this mean? It means that we don't have much control on the orientation of the system. The motion of the BV pounds. As we will see in Zeneca slots. It was only support small BB system such as in our home or in small houses when we would like to provide electrical power to our home. Another type of mounting system, which is the integrated PV panels. Pv panels itself is integrated into the building itself. So as you can see, it is integrated on the roof, inside the glass itself. And here it is integrated on the face of the building, also on the claw, on the gloss of the building. So as you can see this two types. If you remember, we said that there is a type of PV panels that is used in this type of installations. We said before that we use Zazen foam inside when space is not important for us, they give us good luck and at the same time they have very low efficiency. So if you'll remember in the previous lessons, we said that the efficiency of the sinful efficiency is about 7%. If you remember. So it has very low efficiency. That's why we installed large amount of this panels and at the same time it is very cheap. Now let's discuss, since we talked about with the mounting systems, we will need to talk high-powered that tracking systems. So does tracking mean? Okay, So if you look at PV panel here, are what we would like to do in order to produce the maximum power. In order to produce the maximum power possible or maximum possible power. In order to do this, that sun rays should be perpendicular on the PV panels. So the Sunrise itself. So it'd be perpendicular on the panels, all forming 90 degrees with the surface of the path. Okay? So as you know that the sun itself is moving through the whole day, is moving through the whole day. And moving also throws a different seasons. So we can use something which is called the xhat dragging system in order to change our orientation. Or it changes the angle of this bv panel so that it will always track the sun to produce as a maximum power. So as an example, at noon here, you will find that we have sunlight directly on the panels. Then at morning position, we turn the panels to the right in order to face the sun. And that evening we turn it to the left, two phases on. Okay, so if you keep the panel in one position or one orientation, you will find that e.g. in this case, funds at the sun rays are falling like this, which are not perpendicular. Here, are not perpendicular. However, when we change the orientation of the panel width, movement of the sun, we will able to get the maximum power possible. As you can see here, reason PV panels, you can see it is moving through out the day and the year. We this also moves like this one. Okay. Now, how does this PV panels move? They move using an electric mode. So here, this is system is called the solar tracker. The solar tracker is a device that is used for orienting zap the vessel or the PV panels towards the Sun. How does it do this? Using light sensors are connected with mode. So this slide sensors, the sensors are light and according to the signal coming from it, it will cause the motor to operate and causes the orientation or changing the position of this PV panel. Now why do we use a system like this? Because it will help to increase the efficiency or the total power produced, or the total energy produced by 15% in winter and certainly present in some way. Remember, this is not the efficiency of the conversion of the panel. Remember we had monocrystalline, polycrystalline. Each one has its own efficiency. However, 15 per cent here when we are comparing with the output power, what power without tracker and without and power with Tracker. Tracker, You will find that this power is highest, is higher than this power by 15% in one term. And approximately is often present in summer. Okay? So that's why you can use a tracking system. However, is this type of systems is expensive or because you have here a motor and light sensors. So as you can see, it will lead to increasing the cost of the solar energy system. Now, what are the different types of the solar tracker or the tracking systems? You will find that we have two types. First one is a single axis tracker, which it can be vertical or horizontal. Like this one. You can see this is a single axis. What does this mean? It means that it moves along the vertical axis or along the horizontal x. So you can see that this time e.g. it moves like this, up and down, up and down. Okay? So up and down when it moves along the vertical axis, up and down. Okay, so it can be like this. It can be light in this position or it can be like this, or it can be like this. So it is moving in the vertical axis. Other type, which is the horizontal, which is moving like this and like this. So it can be sometimes by exist as our time it will be like zest as our time will be like this. You will see a video now which will chose this types of tracking systems. Second one, which is a dual axis tracker, which have both vertical and horizontal axis. So you can see here this one, which is a dual axis, it means that it rotates in the vertical and horizontal. You can see it can rotate like this and like this. And sometime it can rotate up and down in all of the directions. So of course is our dual axes is much better. However, it means that we have more cost or it is more expensive than a single x. Okay? Here's one of you will have to understand that usually, usually in a small BB systems such as in our home, we don't use any types of trackers. We use the fix-it oriented or the fix it PV panels which does not move. So if you look at here, you can see this PV panel is moving, can see it is moving in both axes, rotating towards the Sun. Like this. As you can see here. You can see it can be, can be vertical or it can be horizontal, or it can be something like this, which is a Doyle x. You can see that PV panel is always dragging some going everywhere order to absorb the maximum power. So before we discuss as a discuss something which is important, which is the angle. We have something which is called the air mass. Okay? So what does air mass mean? Air mass assembly, the proportion of the atmosphere. That's all light must pass through before striking the Earth relative to its overhead boss lens. And it is equal to y over x. Now what does this even mean? Okay. So as you can see here, we have our atmosphere, here is the Earth's atmosphere. Okay? Now, you can see we have this, e.g. is our location here. Okay? Now, this is our son. So before reaching the atmosphere, is there a m is equal to zero because there is no distance. Okay? So am here or air mass is equal to zero. However, when we are directly above as allocation, the air mass is equal to one, which is distance. Windsor sun is perpendicular to that location, biodiversity on it. Now, if the sun have an angle, a certain angle away from the vertical position, you will find that we have here sun rays, sun rays like this. You can see this distance is now different from this one. Okay? So if you look at this figure that this will help you understand. You can see there is our direct space from the atmosphere to xy location. This perpendicular position is called x, or when am or the air mass will be equal to one. So the atmosphere is equal to one. Now when that song form is an angle, it moves like this. It will lead to a larger distance called the y, which is this one. Now, you can see that there is an angle between the vertical position or the perpendicular position and any other position. Now, this angle, when this angle equal to 48.2, we will have a M or the air mass equal to 1.5. So simply what does that mean? Okay, so air mass is the ratio between y over x. You can see y over x. Now if you look at this figure, you can say that here we have 90 degrees. 90 degrees. So this is considered as our hypotenuse and this one is considered as the adjacent. So if we know from mathematics, suppose i1, see that all Trigonometry cosine theta is equal to 0, xylene zeta is equal to x over y, x over y. Now y here. So this will be equal to x over y. Now, as we said now is that air mass is the ratio between this distance y over the vertical distance x. So this will be a mess. So x over y is one over air mass. So from here you can find that air mass is equal to one over cosine. So one divided by cosine of this angle will give us the air mass. So use what is a standard, the value which you will find in PV panels, standard values at which we are taking our measurement or the standard conditions are at air mass equal 1.5. So when air mass 1.5, this is a standard values. Okay? So what does this mean? It means that the angle theta will be equal to 48.2. 48.2. Okay? You can see angle 48.2. So one over cosine of this angle will give us 1.5 LMS. So when you see on the panel that the air mass measurement are taking, the measurements are taken at air mass of 1.5. It means that the angle between the vertical distance and as the current position of the sun is 48.2, this is what does it mean? Does it really matter in anything? No, it doesn't matter anything. This is just for your own knowledge. So when you see air mass 1.5, you understand what does this mean? Okay. Now, if you look at any waveform like this very large wave form, e.g. this 1245 megawatt, which is 2.2 gw as, as, as in India. You can see a larger waveform. And you can see between these panels you have one role than our next row, then an extra one rows, rows. You can consider each row as one string. Can, you can assume this that each row representing one string. Now, you can see that there is a distance between them, between here and here, between each row and the next one, zeta is a distance. So if you look at another one here in United Emirates, you will find that also here. If you look, we have a row of panels here, then the next one. And between them, distance. If you look at this bv panel, there is a distance between them all. So this is a fall in Japan. Okay? Okay. Now, this will lead us to something which is called the Z delta angle and the distance between two panels. So as you can see here, that delta angle of a photovoltaic or a BV array, or usually they all have the same ANC, usually. So that delta angle of a PV array is the key to an optimum energy yield. Now why is this? Because if you look at any panel like this one, we have an angled call that delta angle. Where is the tilt angle exactly. It is the angle between the panel itself and as a horizontal line. You can see this horizontal line here. The angle between the panel and the horizontal line is called the tail tank. Now why is this important too? Because this angle, is this angle important because we are trying, we are trying to make the rays of sunlight to be perpendicular on the panel 90 degree on Japan. Why in order to yield is the maximum power or harvest the maximum power. Okay? So how can we determine this angle? We will learn how to do this in the next slides. So you have to know that solar panels or BV arrays are most efficient when they are perpendicular to the sun rays. Now, zeta sub problem here is that if you look at a panel like this, when it is, has a certain angle, beta, which is a delta angle. Now, e.g. if I install the next one like this, extra panel like this, you will see what you will see that this panel is causing a shadow on this panel, which means it reduces the electricity generated from this panel. This phenomena is called a self shading. So selfish aiding assemblies at each panel is producing shadow behind it. So you can see some rays here forming gas shadow at this regional. Okay? So if we install panel by actually before it, it will be having a shading effect. Okay? So what are we going to do? Simply, we are going to provide distance between each row. So we will provide distance between roles to prevent as a self shading. So if you get back here, that's what I'm talking about. You can see that this panel is a slightly inclined inclined from the ground or the horizontal line by the tilt angle. Okay. So we provide distancing between these two rows. Why? In order to prevent the shadow of this row from coming on this. Okay, So we provide distance to prevent as a self shading effect. Okay? So what is the distance or the distance should be at least three times the width of the panel. You know that any panel has not like this. Let's type it another way. Any any panel, any panel is like this. And installed that likes as the width of the panel. You can see that this panel has a width w. Okay? So in order to between each, each row, we will add what? We will add a distance c, d, which is equal to three times the width. So e.g. if this width is, let's say 1 m e.g. then the distance between each row D will be equal to three times W, which will be equal to three multiplied by 1 m of the panel, which is 3 m. Okay? Distance between pants. Okay? Now how can we obtain the Delta nk? So you will find that if you search for delta angle, how can you determine it? You will find lots of methods to get a little tangled. Mess will actually give us different values, okay? So there is no one correct solution. So here, this is a tilt angle between the panel itself and the horizontal. When this delta angle is equal to zero, it means that this panel will be like this on the horizontal line exactly. So here, this is a standard drove angles between it and the ground, the roofs itself in Australia at 15 degree and 22.5 degrees. So sometimes you can to control it. The panels itself is installed on the roofs with the same angle of the roof itself. You get exhausting, install it directly above the roof. Okay. You don't have any control on this. And then other times such as on the ground, you can control this Nk. So let's say you control this angle and you would like to know what is its value. So here is a beautiful map which gives us an approximate method. Here for different reasons in the wallet, depending on your own location. You will select the optimum angle. So as an example, which I am going to show, e.g. here in Egypt. Here, you will find that the angle is the optimum angle, optimal, optimal. And installation angle for delta angle is between 2060 degrees and sold seven degrees in this range is an optimum ink. Now why it is arranged, why it is not just one value. It is arranged because this angle, it changes through that is through the day. It changes from one season to another. So there is there is no one fix it solution. Okay? So this is a range which can help you. You can select an angle in this range. This is just an overall or an overview about L tank. Ok. So here to give you a point of reference as zero tilt angle. So here you have 15 degrees between it and the ground. So zero degrees, zero tilt angle means that the plan as a panel is lying flat down on its back, facing directly upwards. So it will be like this, like this. So it's facing upwards. So as the inclination increases, the panel would be adjusted to face more and more to the front. So as you can see, when we increase this angle, it is more to the front, more to the front. So as you can see, it is like this, increasing the inclination means like this. And so that, what does this mean? So you have to understand that there are many other ways to get that delta angle. So how can we do this? As an example is a first semester, I will give you some methods and I'm going to show you in the next lesson an example on this. Okay? So here's the first method is that you go to this website of nasa and also to find the latitude of your own place. Let's say you already know the latitude of your own place. Then what is the next step? Assembly If your own latitude of your own location is between zero and up to 25 degrees, then that delta angle will be equal to Sita or data, or the tilt angle will be equal to what? The latitude itself as the latitude L. Multiply it by 0.87. Like this very sim, similar to take latitude and multiply it by 0.87. Second way is that you can say that if you have the latitude between your own latitude of the location 25-50 degrees, then what are you going to do? You will find that Sita in this case will be latitude multiplied by 0.87, multiplied by 0.87. After that, you will add three-point degrees C, we'll say, plus 3.1 degrees. Okay? Now, if you're on latitude is above 50 degrees, then the most ideal angle is at 45 degrees. You will set it at 45 degrees. Okay? Now, this method is used for affix it oriented patterns. You are saying that I am going to put some panels in a fixed location throughout the year. So these formulas will give you the best angle to install your own PV panel. Okay? Now, another method, another method which you can get now let's say you can change the orientation of your own angle or you have a tracking system. So what I am going to do in this case, in this case you will go to this website. This website will give you a solar angle during the year. So you can for each month, you will have the best ANC. Okay? When you go here, as we will see in the next lesson, you are going to select the angle or the best angle in, in each month of the year. Now, the final method or before final method, you can use this calculator to get the angle. This also another website which you can put your own location and it will give you the ink. We will see this also in the next lesson. Finally, you will find that another approximate method and many, many solar engineers use this muscle, is that they say that the delta angle is equal to the latitude of the location. So if you're having a latitude of the location is 30 degrees, then the set delta angle, or the angle will be 30 degrees. This is the easiest method and the most approximated muscle that is used. So you can see we have how many muscles? We have. One method, we have 23.4 muscles. So let's see in the next lesson. By using this, what will be that delta angle and this, and this location. Okay? 8. Calculation of the Tilt Angle in a Location: Hey everyone. In the previous lesson we discussed the shading and the weeds caused all so that tilt angle. Now we would like to provide the different methods of force a tilt angle. Now we would like to see how can I do this for us? Do we have different methods? The first one is going to this website of nasa and then get our latitude. And from here we can get the total tank. This is the first missile. So first I'm going to this website. You can see here Power dot LARC, dot nasa dot government data access viewer. Okay. Okay, so what does the next step? The next step is that I'm going to find my own location. So I am going to get the back legs. E.g. I. Only chose e.g. in Egypt. In Cairo, Egypt like this. Okay? So here, this is Egypt and this is chiral. So what I'm going to do is that I would like to find the latitude of this location assembly. You can see this icon which is used to point at that location. So simple, I will click like this and go to anywhere like this. You can see it's a point to which I selected has a first, you can see a latitude and longitude or longitude. The latitude is salty degrees, 30 degrees according to the first method here. Okay. After going to the website, we get the latitude then if my own latitude, okay, so I'm going to type like this and gets a calculator like this. And so if your latitude is 0-25, use this method, 25-50 use this method. So as you can see, my latitude is 1,330.01 minus three. Okay? So I'm going to type this latitude like this. And which is 25-50. So we will take this latitude and multiply it by 0.87 multiplied by 0.87. Okay? Then what's the next step? Add 3.1 degrees. Okay? So I'm going like this, plus 3.1 degrees. So you can see is that the optimum angle using this method is 29.2 degrees. So this is a delta angle that I'm going to use. Okay? Now, another method which I said is that we can set delta angle equal to the latitude. Latitude itself. Latitude itself is salty degrees. So I can say is that the delta angle assaulted degrees, which is close to this value. Now the third way is that we can go to this website, solar electricity handbook.com and use the solar angle calculator here. This one. This website, this website can help you to get a Z tilt angle for different different monsters. So first I'm going to select the country here, same idea, Egypt. Then the city. Cairo where scale. Let's go down here. Here, Kyle. Okay. So you can see that this website, it gives you what gives you the angle is the optimum angle for E two months. Okay? So this formula which are used here as this formula and this one gives you the optimum tilt angle for a fixed set orientation. In the case of the Bronte, change the angle at all. If you are changing the angle every month, then you can use this website. Now you can see this angle. What does this angle? This angle is between the vertical and vertical and the banner, not between. Note here, you can see delta angle here is between the panel ends the horizontal. Okay. So in order to get the tilt angle, which is a horizontal angle, you will just subtract 90 degrees. Okay? So as an example for here, like this, for summer e.g. or a spring e.g. we have as angle here, this small angle which is between the horizontal ends up panel is 90 degrees -60. So it will give us 30 degrees. For spring. Now for each month here, this angle is between the vertical, so subtract 90 degrees from all of this, you will get the angle between it, Anza horizontal. This is another method. Now the last method here is that using this website for print here. This website can help you to get the solar panel tell tank. So e.g. here, I'm going to say Kyle, like this, Cairo, Egypt. So it will give you here from the horizontal line, you can see the optimum year round tank throws the whole year is 26.6 degree. And using this method here, here, we obtained how much we obtained 29 degrees and this method 30 degrees. So you can see there are different values. Now, this website also gives you the values optimum delta angle by seasons and the by each amounts. Now if you look at here, at this one and get back here to this map, you will find that the optimum angle is between 2060 degrees and 70, 2-6 and seven. And this tool method, this method, this method provides this 29 and so two degrees, which is in this range. Now let's see this one. You can find here 262-646-1611 and so on. So, yeah, Most of these values fall in this region. Most of it. Now if we look again here, so this is Amazon muscle. You can find the IRR for according to the zip code for any. For in the USA, you can get the optimum angle. Pi is allocation. So you can find here that we discussed several methods. And even when you start working with BB sets, the program which we are going to discuss, which is used to design PV systems. You will find that we can have angle which is different from this one too. Okay? So in the end we have different methods to get the optimum angle, but it's the best way in my own opinion, so that you can prevent yourself from different calculations. You can simply use this one, this rule, which is that delta angle equal to the latitude of the location or by using this role. Okay? So in this lesson, we discussed an example on how to get the delta angle for a location. 9. Practical Tilt Angle during Different Seasons: Hey, everyone. In the previous lesson, we talked about the tilt angle and different methods in order to obtain tilt angle. Before we continue this lesson, I would like to mention something which is really important. You can see that we said before in the previous lesson that the distance should be at least between the two rows. Each string should be at least three W. In the previous lesson, it was three W, which is three times the width of the panel. This was not correct. It is the correct answer is that it should be at three times the height of the module. You can see if you look at this figure, you can see we have this module with its own ttgle peter. You can see we have its height. This height is equal two from this figure from this rectangle, this strangle, sorry triangle, this triangle here. You can see that sin, Peter. Sine, Peter equal to opposite, divided by the hypotonus, opposite, which is H divided by the hypotonus. From here, we can get that the height is equal to the width of the panel, multiplied by sine Peter. Now, the distance between here and here, should be at least three times this edge in order to prevent the shading effect. Now, in another lesson, which I will be added to the course, we are going to discuss how can we get the exact distance between the two panels, not just approximate number like three or four. We are going to get the exact value according to each location. Talked in the previous lesson about the tt angle approximate method. We had many different methods to obtain the telt tang. Now, which one should I use or what should I use? You have to understand that engineers or solar engineers. What do they do when they are working in projects? What method they are using? One or large portion of engineers, they use that the telta angle is equal to the latitude of thecation. Many of them just use the telt angle equal to the latitude of the location. Other engineers like me, we use the practical tilt angle. We know that the tilt angle should change through whole year in order to achieve the pest power. Why do we have different tilt angle because the location of the sunny changes throughout the year. You will find that during summer, autumn spring winter, we have different tilt angles. Now, what I would like to get is that what is the pest angle for summer? What is the pest angle for autumn for spring for winter? How can I get the steel tank? You will find that first, we go to this website again for Nasi in order to obtain our latitude or the latitude of our location. Then as a rule of some solar panels should be more vertical during winter to gain most of the low winter sun and more tilt during summer to maximize out. You can see that delt anger is at its lowest during summer, to make most of the sun raise perpendicular to the panel. In winter, we increase the delt anger very high in order to make the sun raise perpendicular to the panel. So what is this value? Exactly, you'll find that. First, I have the latitude, which is the most important value, latitude of any location. What I'm going to do is that, the optimum delta angle is calculated by adding 15 degrees to your latitude during winter. Since we have the higheslta angle, so it will be the latitude plus 15 degrees, for what for winter and subtracting 15 degrees during summer. During summer here, It will be latitude -15 degrees or subtracting 15 degrees. This is the optimum tilt angle to maximize power during summer. This is the optimum tilt angle to maximize power during winter. For spring or fall for these two seasons, what are we going to do? They will be equal to the latitude, the tilt angle here. Will be equal to the latitude. Very easy, right. What are you going to do in practical situations? Very easy? Simply, if you are looking for pest value of delta angle during summer, you will choose this as latitude -15 degrees. If you want the pest angle in summer, you will take the latitude value and add it at 15 degrees. If you are looking for the pest angle during spring or autumn, simply you are going to choose that that tilt angle will be equal to the latitude. As an example, if your latitude is four degrees, the optimum tilta angle for your solar panels during winter will be four plus 15 since we are talking about winter. For summer will be 34 -15 degrees. The spring and autumn, it will be equal to the latitude value, which is 34 degrees. We talked about the optim delta angle. Without thinking, you are already now know the past delta angle for each season. Now, the question is, how can I select the tlta angle if I have fixed panels with a fixed tilt angles. I don't change this angle through the whole year. Which angle should I choose as I choose the summer? So I thro the winter, orso through the spring and autumn angle. Which angle if to select, if I have a fixed til tank. This depends on the type of the system itself. So if we are talking about of great system, it means we have our electrical or our solar panels providing electrical power to batteries or the storage system and our house. At the same time, if we have a solar water pumping system, which we are going to discuss in the course, then what tangle choose so that we will operate through the whole year. Now, one important thing that you have to understand is that We will select the tilt angle to maximize power during the weakest season or the lowest amount of power in the season which have the lowest amount of power. Now, remember that winter is the worst season. Summer have a good amount of energy, fall, spring. However, winter is the worst. That's why since I'm installing an off girt system or a solar water pumping that operates the whole year, then I will select the tilt angle. That is suitable for the worst case. Which means I'm going to select the angle as latitude plus 15 degrees. If I'm having an off grid system, I will choose it as latitude plus 15 degrees, y in order to maximize power during winter. Because I I will get good values of electrical power for in summer, spring, and autumn. However, winter is the lowest season. Okay. What about of grid system that operate only in summer and water pumping system that used in irrigation only in summer. Then of course, I'm going to choose the best angle for summer because it is only operating during summer. The angle during summer is a Talt angle, which is latitude -15 degrees right as we discussed before. Now, what about grade system? Grade system here, I'm talking about a system that's connected to the power grade, providing electrical power to the power grid, or it can be hybrid providing power to the grid and at the same time, providing power to a house. Anyway, in this system, if you are talking about grade, it doesn't matter. If we are in summer winter spring, we need to maximize the power through the whole year. We will select the tilt angle equal to the latitude. Why? Because if we are, for example, inventor and the panels are generating lower amount of electrical power, I will get the excess or any extra amount of power needed from the electrical grid. However, the of grade system, you are not connected to the grid. You need to have electrical power the whole year, not the maximum power, but we need power through the whole year. If you see the newer versions of PVs program, which we will discuss in the course. In the newer versions of PVs program, you will find that. If you are talking about the design of the of grid system, you will find that it gives you a suggestion for maximizing power during winter. If you are designing on grid system, it will select the angle that will maximize power through the whole year, which is equal to the latitude itself. Okay, so I hope the idea of the tilt angle is clear now for you. So you now forget about the previous lesson. If you are having any kind of confusion, simply you can just use this method that we discussed. Latitude. If you are if you are designing of grid, it will be latitude plus 15 degrees of grid system on grade system, it will be latitude. If you are talking about systems during summer only, it will p -15. During winter only, it will be plus 15. If you are maximizing through the whole year, similar to the grade system, then you will just select the silt angle equal to the latitude. 10. Orientation and Azimuth Angle of Solar Panels: Hi, everyone. In this lesson, we will talk about the orientation. We talked before about the tilt angle of the solar panels. Tilt angle, how much it will be inclined from the horizontal position. Now, let's talk about something really important. The orientation of the panels means I'm going to direct my panels through the South, or I'm going to direct it through the east or through the We West or through the north, nor south east or west. What direction should I choose? This is related to something which is called the Asmus What is as Asmus is the angle that the solar panels are facing and it's measured in a clockwise direction from the northe. We have the line of the nose. Let's say, this is the line of the nose. Let's just draw it like this. This is the line of zs. You can see the direction of these. Now, the angle from here to the direction of panels, you can see the panels are in this direction. This angle you can see here. Between line of the norse and the direction of panels is called the sms angle. This angle representing the angle of orientation of the solar panels. This is different from the tilt to angle. How can I determine this type of angle? How can I get it? First, you have to understand where simple thing, if you are in the southern hemisphere, we are in the North and South. In the southern hemisphere, you are going to direct the panels to the north. If you are in the Northern hemisphere, then you are going to direct the panels to the South. If you are in the north, you will direct to the South. If you are in the South, you direct it to the north. Why in order to face the sun through the whole as we can? Why? Because this affects the generation of the panels. As you can see if you are in the Southern hemisphere, the sun will be in the Northern sky, the panels should face the North. If you are in the Northern hemisphere, the sun will be in the Southern sky, so the panels should face the South. You will find a tool that I'm going to show you right now that will help you get the exact g. How can I get the Asmos angle? Simply will find that you are going to go to this website footprint hero.com slash solar panel AsmoS Angle Calculator. This will help you get the exact angle. Very easy. Before we go to the lot, let's go and do or get the Asmus angle for any location. We went to the footprint here, the solar panel Asmus angle calculator. This is really easy to find the past direction for the panels. Direction orientation. Let's say, for example, use your current location or add any address or set. As you can see, you will see that here. The north south east west, or west. As you can see here that the angle should be 4.8 degrees east of magnetic south. You can see that your optimal Asmus angle is true south. What does this mean? It means that myself or my location is in the north in hemisphere. My location is in the northern hemisphere. I should direct my panels into the South. That's why it say the esmo angle is in the South or true South. By how much you will get this by using this calculator. You can see that your esmos g can be suppressed as 175.2 clockwise from the magnetic north. As you can see, we have the north. The angle from here, all of this, this angle from the north to this line is 175 degrees. My panels will be directed to this location. It will be looking at the South. Simply using the compass, you will be able to direct the panels. That is really easy you just add the location and you will get the angle. So now we talked about the how to get the asm angle exact. To direct our panels. Now, the biggest thing that we would like to see is that what is the effect of the Asmus angle and the tilt angle? Let's see what is the effect of the Asmus angle or the tilt angle. What happens if I don't direct it into the correct location? So for example, the asthmas here. Here, let's say, for example, my correct orientation is zero degrees. Now, how much losses I will get, if I am directing my asthma to any other degrees. For example, if I am, my correct location is zero degrees, and I'm directing my panels to the west. How much degrees? If you are directing an extra ten degrees, you will suffer from 0.36% losses, 20 degrees, 1.14%, 45 degrees, 5.15, 70, and so on. You can see that the losses increases as a degrees increase. However, these losses are not that big. That's why if you have solar panels installed on a roof, you don't have control on the orientation, and you don't have much control on the tilt. That's why it will not affect much your generation. If you have a control on the asm, try to be close to the correct value. However, if you don't have any control, then you install these panels with the same angle of the roof. Now, why this will not affect Because you will have to understand that when I am designing my BV system, my solar energy system, the of grade system, I usually add 20 to percent losses in the system. This 20 30% will accumulate or will compensate to pay more correct compensate for the losses, losses in the tt angle, losses in the cables, losses in asm, that 20 and 30% value will compensate for any kind of losses in the system. Don't worry much about the incorrect asm. But if you have a control, you have to make it in the same direction or the correct direction of the Asmus. For the delta angle, for example, all of these values are obtained from one of the websites, one website that I have seen. That's always the effect of Delta angle from the optimum. As you can see as you change delta angle, how much a percent you are suffering. You can see that there is no much as a percent is 0.1% or 0.449%. You can see very, very small change. Anyway, you don't have to worry about the losses due to the tilt angle and esmos because you are compensating this with that 23% when designing the PV system. We talked up out here and this lesson, we talked up out the Asmos angle and how can we get it? 11. Sun Chart and Distance between PV Rows: Hi, and welcome everyone. In this lesson, we will talk a poet, the distance between BV or solar panels rows. If you remember we said before that each row of panels, there is a distance between them to avoid the shedding effect or the shading effect. The distance between them, we said before, it is approximately three to four times the height of the panel. However, I would like to get it more accurately. I would like to get the correct answer for each location and each situation. How can we do this first? As you can see here here, we have an example. We have our angle, the tilt angle equal to 15 degrees, and of course, this one have the same tilt angle of 15 degrees, and we have the width of the panel itself is 39.41 ". This is the width of the panel itself. What are we going to do? First step is that we would like to get the inter rose pacing for uro modules. What does this mean? What I mean is that I would like first to get the distance from here. You see this point here, the point corresponding to here from here to here. That is the first distance that I would like to get. Then I will add this distance to get the total distance, which is the module raw distance. The first step that we are going to get is that this height, I would like to get this height. As you can see, we have 15 degrees and we have 9.41. As you can see from here from trigrametry, that sine Sine Peter or sine the tilt angle is equal to opposite, opposite, sine of the angle is opposite, divided by the hypotonus. We have opposite, which is, and the hypotonus, which is the width. The height, if I would like to get the height, it will be sine Peter, which is a tilt angle, multiplied by the width of the solar panel. As you can see sine angle, multiplied the modules. It will give us the angles, and this angles will be in degrees not radians. As you can see in this example, we have sine 15 degrees multiplied by 39.41 equal to 10 ". So the height here is 10 ". Now, what is the second step. Second step is that we would like to get the shadow angle or the sun elevation angle. What is this angle? As you can see this figure here. We obtain the first step that we obtain. Now what I would like to get is called the shadow angle or called the sun elevation angle. As you can see when the sun falls on the panel, you can see there is a shadow here here. At this point, all of this is shadow. And you can see that the sun forms an angle with the horizontal line called shadow angle or the sun elevation angle. Sometimes the sun can be like here in this situation and falls on the panel. It will form a shadow like this. This part will be shadow, and this will be the new sun elevation angle. What I would like to get is the worst case, which means the smallest shadow angle that gives us the largest shadow. I need the worst location at which will give us large shadow, the worst t case. In order to do this, we need something which is called the Sun chart. This chart differs from one location to another. As you can see, we are going first to go to this website. This is a very important website that everyone uses Sun chart program. Of course, you can go to this website using the slides or the BDF slides that you have in the course. After going to this website and entering the location details, such as the latitude, the longitude, the time zone. After doing all of this, you will get a chart for your own location like this. Now, what does this chart represent? This gives us the sun elevation. Sun elevation throughout the whole er and gives us also the solar sms from east to east. The movement of the sun is from east to east. As you can see here, we have 5:00 A.M. 6:00 A.M. 7:00 A.M. Am and until 7:00 P.M. As you can see what happens is that as time passes. First, each of these lines, each of these plu lines, representing amounts. As you can see, June 21, May 21, April 20. What does this mean, it means that tie of April, 20 M, February, Jane, 21, Deber 21. What does this mean? For example, this one, it means the day 21 of June. To 21 of June, the day and the months. This is a 20 day of April, to 20 day of March, and so on. For example, let's look at June 2021, this big one. As you can see, starting from 5:00 P.M. The sun will start at 60 degrees asm and zero sun elevation. As the time passes, the asm will increase keeps increasing from east to west or west west east and west. Starts from here going to 300 degrees. As you can see, goes like this. The sun elevation will start increasing, as you can see here, elevation of the sun stars increasing as the time passes until reaching the maximum Asmus. This happens through each day of the months. Now, you have to understand that the worst case is that or the worst case scenario when the sun is very, very close to Earth is at December 2021. Sumer 21 for the worst case scenario. As you can see here, If you look at this figure, this one is December 2021. In this case, what are we going to do? We are going to big this curve. You can see this big curve. This one. This is the same case for any location. Now, what is the next step? You are going to take the curve of 9:00 A.M. And 3:00 P.M. Then you are going to go like this until the intersection here with this 21 December curve. Here like this, go here. As you can see the intersection between the time frame and the December 21 curve. Is this point and this point. Now, what is the next step? We are going to provide a horizontal line. We are going to provide a horizontal line from here like this, bussing through these two points until we intersect with the sun elevation. This will give us the solar elevation angle at the case, which will give us the largest shadow. Here this intersection with the line gives us 17 degrees. As you can see here, the intersection gives us 17 degrees. Now, 17 degrees as you remember from the curve, here the shadow angle here in the worst case is 17 degrees. How will this help us? As you can see is 17 degrees, and we have the height which is 10 ". From this triangle, this triangle here, this one, 90 degrees, from this triangle, we can get the distance from here to here. How it will be ten 17 gives us 1017 is the opposite, which is a 10 " or edge divided by the adjacent, which is a row distance. Distance from here to here. As you can see here, Module row spacing, what does module row spacing mean here? It means the distance from here to here. The spacing between the two modules, not the whole distance. Just this distance. It will be, which is the height divided by ten seen gives us 3 ". This distance here, This distance here is 33 ". What distance exactly from here to here. However, however, there is something which is really important. As you can see that the sun itself, it's location, it changes with time. You can see the solar sms for the location of the sun itself, it changes through the whole time. From 9:00 A.M. To 3:00 P.M. And our BV panels are installed, for example, at 180 degrees, asm There is a relative Asmus between them or a relative angle between them. We need something which is called the Asmus correction. How can we get this? You can see that the sun is moving through the whole time? However, our panels are installed at a fixed angle from the north, if you remember, the orientation that we discussed in the previous lesson. What are we going to do? Simply you are going to take this space from here, which is at 3:00 P.M. Tone pm, this angle. The difference between this two and divided by two, to give us this distance and this distance. You'll find that this angle, which is the difference between this angle and this one is 44 degrees, and between here and here is 44 degrees. 44 degrees is called the sms correction angle. How can I use this? You can see this angle? What are we going to do with it? This will give us the minimum distance. As you can see, the 33 " is excess distance. More than required. How How can I get the minimum value by using the correction? In order to do the correction, we will do like this. The minimum module row pacing. Which is distance from here to here will be the 33 ", which we just obtained multi blood by cosine the as mos correction angle, which is 44 degrees. This will give us a smaller distance of 24. Instead of having a big distance of 33 ", we can just take 24 ". We reduced the distance required between two modules. Or between two rows. Now we obtain this distance, right, which is at 24 ". Now I would like to get the module row distance, the whole distance. It will be that 24 plus this part. Which is 39 or the widths of a module, multiplied by cosine 15. It will be like the zow widths, which is a minimum equal to minimum module row spacing, which is a 24 " that we just obtained plus cosine telt angle multiplied module widths. We can see cosine of this 15 degrees multiplied by 39 gives us this distance here. This distance. By taking this distance and adding it to this one, we will get the whole distance. It gives us a minimum rows of 62 ". Now, as you can see, as you can see, 62 ", which is a distance from here to here. Now let's look at the height. We said before that the distance between two rows is at least three to four times the height. Three to four times the height. It will give us what? It will give us 30 to 40 ", which is not enough. That's why we need to do this calculation in order to get the correct module row distance. What are we going to do next? Now, what we are going to do is that I would like to show you how can you get this curve? This is the important part. How can I get this curve to get the sun elevation. Let's go to the website that I just showed you and let's see how can we get this curve? If you go to the website that I just showed you, Sun pass hart program. Let's refresh this page. We have the first things you are going to do is that you enter the latitude and longitude of your own location and remember in degrees. Again, we will use the power data access viewer from NASA. Similar as we did before, here's my own location in Cairo, Egypt. I'm going to take this longitude here. Or the latitude, sorry, the latitude. First one is the latitude and the longitude, latitude, longitude, latitude and longitude. Okay added here. Okay. You can add also the Zip code if you are in the US. We add the first latitude and longitude. Second thing that we are going to do is that I'm going to si fy the time zone. You can see here the time zone in UTC. What I did is simply I typed in Google, UTC Egypt time. W you can see is plus 2 hours. You can do the same for your own location. I will go here and just type plus two UTC plus 2 hours. Now you will keep everything as it is. Don't worry about anything, and type this verification number, and then create chart. Then click here to download your BDF. Okay, now we have this chart. Let's rotate it. View, rotate view, clock wise, like this. You can see this is the figure for the altitude and longitude, as you said, for the time zone. As you can see here, you can see that we have the linim and the 3:00 P.M. Then we will make a horizontal line here, and then we will get the intersection angle. Then we are going to measure the sms from here to here and vd it by two to get the correction angle. Very easy. This will help you in the end in obtaining the telta angle, not the telta angle, the distance between two rows in a BV system. I hope this lesson was hel buff for you. 12. Important Note Regarding the Sun Chart: Everyone. In this video, we will talk a poet, a very important note regarding the distance between BV rows. If you remember in the previous lesson, when we talked a, the distance between BV rows, and when we talked a poet, the usage of the solar chart in order to get the solar elevation angle or the shadow angle in order to find the distance. Now, there is a very important note here. That when we go to this website and add our location, such as the latitude, longitude, and the time zone, there is something here which is important is that when we get this sun short, this sun short will be different from in two different cases. If you are in the Northern Hemisphere, it will be something like this. If you are in the Southern hemisphere, it will be different. Here, when we are designing, similar to what I did in the previous lesson. If you are in the Northern hemisphere, You are going to sign during winter, which is in the Northern hemisphere is in December 21, 21, December. This one is the worst case between 9:00 to 3:00 P.M. From here to here. However, however, this is really important. If you are in the Southern hemisphere, The winter will be in June 21, not in December 21. Here if you are in the Southern hemisphere, you will find that the lowest curve here will be June 2021 instead of December 21. This is really important. You do the same process, the same steps. However, if you are in the Southern Hemisphere, we are looking for the curve with June 2021. Let's go and let's have an example on the sun short for South Africa, which is in the Southern hemisphere. Let's see how it looks like. As you can see here, the same website here, and in this case, I'm going to use South Africa. South Africa have this latitude and this longitude, 30.5 and 22.9. 30.5 and 22.9. Now, there is a very important node here that if the latitude in the South in South or the latitude is South, you need to add a negative sign. Let's look at here. We can see in South Africa, it is South. What does this mean? We need to add a negative sign. We can see here, I have added a negative sign. For the second one, if you are in the West, Northeast, you are in the West, Northeast, you will add a negative signs. Let's look at here, we are in East, so it will be positive. This is really important. Now, the second thing that we are going to do is the time zone. If I go here and search for time zone, South Africa, UTC. It is plus two, let's go here, UTC plus 2 hours. Then after doing this, you will click on Create chart. Now you can download the BDF. Now, let's compare between Egypt, which is my own country in the Northn Hmisphere. Compared to the other case, which is South Africa, which is in the Southern hemisphere. This one is a short for Egypt, as you can see latitude and longitude, and as you can see here, this one is December 21. What you can see here is that each of these curves, representing June 21, May 21, April 20, sunshart, for a specific day. For example, here tie of March. A specific date. Since I am in the Southern Hemisphere, Egypt in the in the Northern Hemisphere, we will choose December 21. We will look at nine curve intersection between nine M curve with December 21 and 3:00 P.M. Curve with December 2021. This is the intersection here. If you extend the line here, you will get to 21 degrees, which is the lowest solar elevation or shadow angle. Another thing here is that if you remember the Asmus correction, why do we add Asmus correction? Because if you remember, since we are in the northern hemisphere, we are going to direct our solar panels to the South, which means the Asmus angle is 180 degrees. The Asmus should be 180 degrees. However, these values here and here at a different Asmus. You can see this one at sms approximately 130 degrees. Or 125 degrees. This one, for example, is about 225. This Asmus here. However, our panels at Asmus hundred 80 degrees. Why? Because we are in the northern hemisphere. The distance between here and here or here and here, the difference here, we will use this as a correction Asmus This is for the Northern hemisphere. Now let's look at South Africa and understand the difference. Sshot for South Africa. If you look here, the first thing, the first thing that you'll notice is that December 21, January 21, February 20, March 20, and so on until June 21. You can see the lowest curve here is June 21. Unlike Egypt, which is in the Southern hemisphere, December 21. Why? Because South Africa is in the Southern hemisphere. Another thing you look at here is that the Amos. Since South Africa is in the Southern hemisphere, the sms should be zero. The smus angle should be zero of the panels. You can see here zero here, exactly here, zero, compared to Egypt, which is 180, since it is in the northern hemisphere. Now, another thing here you can see is also here, June 21, you can see 3:00 P.M. Here. And nine, we extend a line here until the intersection here to get the solar elevation angle and do the same process of what we did in the previous lesson. This is a difference between sun chart of a Southern hemisphere country and sun chart of a Northern hemisphere country. The asm Correction angle because 180 is our reference. Here for South Africa, also we have a correction angle because zero is our reference. And we do the same process. I hope this clear something which is confusing for many of you that are living in different parts of the world. 13. Panel Parameters and Measurements: Hey everyone. In this lesson, we are going to talk about some of the parameters and how to do that open circuit and short circuit, or how to get the connections of the different testers involving the panel's first panel parameters and power. So if you look at any panel, any imbalance, okay, you will find that it has a data sheet. Okay. This datasheet show with us the different parameters of subpoena, e.g. it's always us that maximum power produced by a panel, which is e.g. here, maximum power is 250 watt. This is the peak power of the panel. Now, when do we produce this power? This power, or the maximum power, is produced add conditions called the standard test conditions, or SDC, SEC, or the standard test conditions. What does this mean? It means that we test that our panel, when we have irradiance falling on it with 1,000 watt per meter square. And at a temperature of 25 threes as the green. And that air mass of 1.5, which we have discussed before. At these three conditions. When we test our panel, we will find that the maximum power which can be produced is 251. Okay? Now we have also the open-circuit voltage and short-circuit, which we haven't discussed it before. When we leave our wires open, two terminals open and we measure the voltage. And when we connect to that, connect these two wires together, the two terminals together, we will have this short-circuit current. Now we have also the optimum operating voltage and optimum operating. What does this mean? You can see here v and maybe, which is the voltage at maximum power. And I am maybe means the current at maximum power. Okay, so in order to get the maximum power of 150 from the turf, if you remember it. V and I like this or I and V to be more specific like this. If you remember the curve, it was something like this. So it's a point of maximum power point at which we will have maximum power. Maximum power. This point is occurring at the value of current will be 8.87 and bear, and value of voltage would be the 0.10. Okay? Okay. Here this is a voltage and this is a cat, okay? This is a short circuit current. This, if you multiply 2.1 multiplied by 8.32, which is the values at maximum power, you will get the 250. Okay? We have another three parameters here inside the datasheet of the panel. You will find your temperature coefficient of B, maximum temperature coefficient of V open circuit, and temperature coefficient of r in short sec. What does this even mean? You can see that the temperature coefficient b max, we have our Power BI max equal to 250. Okay? Now what does this mean? Negative 0.44% bare Celsius degree. So remember that this power is at the STC conditions of 25s reserves degree at temperature equal to 25 citizens degree. Now, let's assume that the temperature is now equal to 26 Celsius degree. So what happened here? The temperature increased by 1 c degree. The temperature increased. And as we remember that when the temperature increases, the voltage will decrease and the current will increase by a very small value. So how much is our panel up? Our maximum of the panel will be at once Lisa's degree. When at 26 degree, you will see that here. It says that negative 0.44 per cent bear, so this has degree. So it means that our p nu, then your maximum power at as a 26 degree will be equal to. There are 250 -250, multiply it by 0.44%. So our power will be decreased by 0.44% for each 1 c degree. Now let's say the temperature, and instead of 25, it is Celsius degree. So in this case it will be 250 minus z decrease in the power due to the increase in temperature. You can see 25 became salty. So this is degree. The difference between them is five. So this is degree, so multiply this by five. So here it is a reduction in power as a percentage bear solicitors degree is the same idea for the voltage. Voltage V open circuit is here, 7.7, 0.5. Now, for each temperature rise, we will decrease by negative 0.3%. Okay? So here, e.g. let's delete all of this. So let's say the temperature again is 26 Celsius degree. So what will happen to the voltage? Voltage will be open circuit, which is 7.5 -7.5 multiplied by how much? Negative 0 point here, negative 0 point C. Okay? So here our voltage will decrease by this present. Here we have our present. Remember, now what about the current will increase by a very small value, 0.04. So instead of negative, it will be plus. Ok. So here you will see that the power and voltage decrease by 0.44 and 0.3 h, or current itself increases by a very small value. That's why it's a total power decreases. Okay? Now you can see here what is the maximum system voltage? It is a maximum value of the voltage of the system itself. Okay? So when we can connect as a panel together and form a string, the maximum operating voltage of this string must be 600 v DC. This is a maximum value. And you can see here maximum series fuse sizing rating. Here we have a few rules which you will use to protect our BV banners. We will learn of goals in our course. How can we select the diffusers and cables, the maximum fuels when we are connecting the panels in theaters, maximum one is 15 amperes. Okay? Okay. Here you will find that fire rating, which is not important for us. We have the weight in kilograms and pounds, and we have the dimensions which is length multiplied by a width, multiplied by setups in millimeter and in edge. And this is our STC conditions here, as this image is taken from clean energy reviews or clean energy fuels data, dot info. This shows you the top electrical panels in 2022. Okay? So this is a top panel. So what I would like to say here, you can see that all of these panels are half cut cells. Because we said before that half cut cells is much better than a fall monocrystalline cell. Okay? So here you can see this is the highest panels with the highest power. As you can see, this panel, e.g. has 120, 144, 156, and so on. But you'll notice something which is important that solar panel size versus power output. You can see that as the power increases from zero hundred to 560 or 680, you can see that the dimensions of the panel itself starts increasing. So more power means that we will meet need more area of our manner, okay? Because it will absorb more energy or more irradiation from the sun. Okay. So what about Bannon power? Usually you will find that this panel power or the BV system is rated in kilos. What beak? You can see this value of power, which is a P maximum representing the peak power. So we can say is that this one is Zach kilowatt peak of the PV system. So what does this mean? It means that e.g. if we have PV system, which are consisting of several strings or arrays, we have seven kilowatt peak. What does this mean? It means that this system or this solar energy system. Has a maximum output power of 7 kw. It is the maximum possible power that this system will produce at STC conditions. At STC conditions. Okay? Now, as you can see that here before we continue, you can see is that of course, the power output of the PV panel is affected by the temperature, as you can see, and also affected by the irradiance. So how can we know this? We need to find the data of the irradiance and finds a data of temperature in our location that we can size our system correctly. Okay? So here you can find that this is essentially the rate at which it generates energy at peak performance. Maximum power, e.g. at noon we have the highest radiation from the sun. So this is the time at which we will have the maximum possible power. Kilowatt peak of domestic system will vary depending on how much a customer wants to spend and the area of the roof available. So usually we are limited to the area of the roof. Okay. If you are and installing PV panels for your own house, then you are constrained or you are limited to the area of the roof itself. You don't have much space. So depending on this as base, you will install PV panels and you may reduce your own electricity. But we can know that radiation of allocation required to Angular of the BV and temperature using the global solar eclipse. So here, as I said before, here as I said, we said here is that we have the radiants and temperature are very important to know. So how can I know the regions of any location and the temperature of any location? We use some a website called the Global Solar Atlas. Global Solar atlas. If you go to this website and selected your own location, you will be able to find that optimum delta angle again. And you will find the radians values or radiation values. And you will also find the temperature of the location. So as an example, if I go to the Global Atlas and I selected the same location as before, Cairo, Egypt, which I have selected in the previous lesson. You will find that the irradiance here, here it is given the regions. You can see that here, the direct normal radiation. And we have global horizontal irradiation, Diffuse Horizontal irradiation, and the global tilted radiation at optimum angle and so on. So different types of radiation which we will discuss in another lesson. I will discuss them so you can understand the difference between them. So anyway, for now you can see that this website helps you also to get the optimum tilting and you can see 26 degrees, okay? And also this website, if you go to more details, it can give you the direction of the run. Is it directed to the east or west or north or south? The website itself shows you it gives you the four directions, north, south, east, west, west to east, west. Okay. And it gives you the direction of the panels. So you have the panel itself, an angle, which is the tilt angle which we have obtained using several methods before. Using several methods that before. And we have, we need the direction. Which direction, which, which one of these four directions? You will find that e.g. it will give you some single axis. So it means that we should direct our panels to the east, south or south or east. Okay? So now you have the angle which is the triangle using the methods it before or by using the value here, optimum angle obtained by the global Arctic's, you can see everyone is giving you different delta angles. So there is no one solution. There are several Delta angles for the same location. So you have the tilt angle and you have the direction. You can see also here. Here's the different types of radiation and you have here also the air temperature. Remember that our panel is at 25 citizens degree as I peak power, peak power. Now from this, you can identify them. Since you have here 22.6, you can see the difference. The output is the maximum output power and the open-circuit voltage. So this will help you to get more data about the BV system, okay? How can we do the BV panel measurements? So here, as we said before, we have our meter. The meter is used to measure current and use it to measure the voltage. So as an example, if we have a battery or our BV system, which will give us two terminals. Positive, here, negative and here we have posted two terminals. Now what are you going to do? Assembly, okay, not this one. That says delete all of this first. Here we have the positive terminal and the negative terminal. So usually you connect, connect his arm, Steph terminal of a battery or a B visa system with the red measurement port, which is connected here to the PowerPoint. And the negative terminal. Here you can see negative or the current coming down like this. So the current will flow from battery like this through the red port and go to the device and then comes out from the COM port. The compound here is the one which you will connect to the other part of the rim. So you can see this meter is in series, so you have something like this. You have a battery plus minus. Then you have here the current measurement here. You have the current image element in series. We have supposed of terminal and the negative terminal. So you can see poster, poster, you can see both step was opposed. Okay, then the negative terminal is connected to one part of the lab. Let's say it is a resistor. One part of the lamb and the other part will go to the next part. We'll go to the negative part. Okay? So here you can measure, you can measure what you can measure the short circuit current of a panel. Okay? Now here's the same idea. You can see here. Not the, not the short-circuit. It will measure the current in general. Okay? Why it is not a short circuit? Because we have a load here. If we cancel this load and connected this part by rectally exists, then we will measure the short circuit current. Okay? You will see all of this in the next slide. Here you can see as a same idea for measuring the current. This idea is similar to this one for the voltage. Voltage, or the meter is connected in parallel with the load. You can see we have the PV panel like this pose step and the negative terminal. So we connected this one here bolstered with both positive and the negative was negative parallel to z. You will have something like this. You can see is a panel like this, plus minus. Like this. This is our panel. And we connect a Lexus, the meter parallel to it, parallel to the load, which is more like this. Okay? Okay, so here you can measure the voltage. So here we measure voltage and here we measure current. Okay? So here you can see this is the open circuit test, or we are measuring the open circuit voltage. So you can see we are connecting one terminal to the voltage part of the gravimeter and other terminal to the com. Okay? So here you can see we are having e.g. here, positive and the negative terminals of the panel. We will put it like this so we can measure the voltage we want at one terminal and honors often. Okay? Now the same idea for the short-circuit current, same part, but you will connect to the ambient. So instead of here you will connect the red one here. I'm pair part. And the negative is connected to the column. Usually is a negative is a black one, and red is positive one. So here we will measure the short circuit current. So now Let's see this practically, this is, this video is from somewhere Company K for PV systems. You can see that here. Let's go a little bit here. Like this. You can see that first, if you look at any, any panel, you will find two terminals or two types of terminals. One which is like this. We have a red one and the blue one. The red one is the positive terminal of the BV or the PV panel, and the blue one is a negative term. So all Steph terminal negative Turner, same idea. You can have, you can find some panels have blue, green, and red. Same idea as, as here. If you measure the voltage between blue and red. You will get the open circuit voltage or the total voltage. Similar to if you measure here and here, it will get the total voltage. However, if you take the green one and the red one and started measuring the voltage, you will get half of the voltage. So again, red one, red one is usually post them. Blue one. Blue one is usually negative. Measuring in-between them or adding the elbow meter. You will get what? You will get the whole voltage, complete open circuit voltage. Here. If you same idea, take red, which is supposed to have and the blue is a negative. If you connect the meter between them, you'll get the whole open-circuit voltage. However, if you connected between here and here, you will get half of the voltage. Those are two, the two types of terminals of BV system. So if you go here, you will find that we have our album ID. First. You have to select, are you choosing voltage like here? Or are you selecting and pair? Okay, you will find here, if you are measuring the open circuit voltage, then you will select the voltage here. If you are measuring Zach current, then you will select the current t here. Then you will find here, Zach, come, come here, which is that black one is the ground. This one is always used. It is connected to what? Connected to that blue line because it is a negative ten. And you will find the other two terminals. One which is an bear, one, another one is milli ampere and voltage. If you would like to measure the open circuit voltage, it will take v. And if you would like to measure current, you will take milliohm bear or the 10:00 A.M. bear and the Tsar. Okay. So as you can see here, here we have the BB junction box, a very small junction box here with the two terminals. Okay, So if you go here, you will find here we have the red one, blue, and green. So if you go like this, okay, now you can see here we connected, you can see black here. Let's take it back a little bit here, like this. Okay, so first you can see black connected to that Guam. And the red one is connected to a voltage. Okay? So here we are measuring the open circuit voltage. So we will connect the sensors. S1 is a negative or the ground. We will connect it to the blue one. And then we will connect to that red one, to the right one or both step toward, you can see here Y exists. You can see as a blue one connected with the black line, is the red one connected with red wire. Okay? So you can see here red and blue. Now we find that the voltage showing here, 20 volt, this is what, this is the open circuit voltage of our BV panel here. Now, if I would like to measure as a short circuit current simply will take that red line, this red line, and put it in milliampere or the ten and bear. So a fund like this, you can see here, as you can see here, we switch it to, we will switch it from voltage and go here to the other side with current, as you can see here. Like this. You can see here, current. Here we have the voltage, and here we have the current. Okay? Okay. Now you will take the instead of red terminal from here and put it here at the current point. Okay? What should we have done right now? Okay? So as you can see here, here we have voltage. When we measure the voltage, and here we are going to measure the current and the comb is at as it is. Now. We will take the black and the boat it here with a blue one and take the red was read, as you will see now. So we'll take this one here like this with that clamp. Remember, I think it's called clam. You'll find that the current measured, dc cannot measure is 0.01. Very, very small current or very small short circuit. Now why is this? Because there is no much light in the studio. Very weak radiation. So the current, output current is very, very small. So in this lesson, you will learn more about BV panel parameters. And how can we measure the open-circuit voltage and short-circuit current. 14. Junction Box in PV Panels: Hey everyone. In this lesson we are going to talk about the junction box inside PV panels. So if you look at any PV panel, you can see we have the front of the PV panel with its own widths and lengths. And of course, sickness of the PV panel. This is the front of the PV panel. Now if you look behind at the back of the PV panel, you will find here a box. Here, this box, this box is known as the junction box. Now what does it contain? It contains the positive and negative terminals of the panel. So if you remember that any PV panel, any beaver panel has two terminals. All step and the negative we have the two terminals which we are used to connect to another panel or to take the output power. Now, if we look at this figure, you can see that here we are using a type of cables called MAC for connectors. The MSE for connectors, which you are seeing here. This what are they used for? They are used to connect between two panels. We can connect them together to form a string or in parallel, such as in a combiner box, and so on. Okay? So as you can see, we have two terminals, one which is a positive and a negative. And then we start connecting the two bands. So you will find is that inside the junction box there are diodes. Now what are these diodes as they are the rights which we discussed before. So we'll find that we have two types of diets in the PV system. Remember that we talked about which are bypass diodes in order to solve the problem of that shading effect. So remember, each part of the panel has a pi, pi S bypass diode. Remember it. Okay to bypass our panel if it has a problem of shared or has a shading effect. Okay? Now we will find that zeros, another type of diets called Zap locking died. Now what does this dye do? It simply prevent the power flow from the battery to the panels. Okay. So as you know that during the day during the day, the panels are supplying electrical power to the battery to charge the batteries. Okay. Now, at night, this panel's does not produce any power. So if there is no blocking diode here, what will happen is that this battery will start giving electrical power to our panels, which will lead to burning of zeppelins. Okay? So we need a type of diet called a blocking diode in order to prevent as a power flow from the battery to the panelists at night. Okay. So what are diodes inside the junction box? As aldehydes inside the junction box are one type which is a Pi, pass diets. Okay. Now where are the blocking diodes? Are blocking rights exist inside there? A charge controller, which is used to charge a battery. Inside it, it has the blocking bytes, which you prevent this up outflow from battery to that. Okay? Now, if we look at the junction box here, here, this is our junction box, okay? This part. Now if we look at it closely here, you will see that we have two terminals. You can see here posted as you can see posted here. And you can see negative. So we have Falstaff terminal of that panel or the junction box, and the negative terminal of the junction box or the panel itself. Now if you look at here, you will see that we have here as our diets, this diode and this one, and this one. All of these, all the three are diets. They are connecting 12-3 and four bus bars. Okay? We will see the equivalent circuit of this in the next slide. But for now you have two nodes at the junction box is an enclosure on the module or the PV panel where the BV strings are electrically connected. You will find that inside using this junction box so we can connect to that BV strings. Okay, Since we have here one terminal poster, another terminal point negative. And we have another panel like this with a whole step and the negative terminal. So in order to connect them in series, we will take this slide exists positive or negative, and then bolstered with the next and negative and so on. So we will have in the end two terminals, as we discussed before, when we learned how to connect strings in or panels in series. Okay? So by using the junction box, there are two terminals, so we use them using MAC for k walls or connectors. We can connect between panels in order to form strings. It is fine. It's found on the back of the solar panel. It wires usually for connectors together. And it is our interface of the solar panels. As you can see here. What does this mean? You can see for connectors, you can see 1.2 and 3.4. So this junction box connectors between four bus bars. Now what does this even mean? You will understand is Anika. So slide. When buying the solar modules, we have to look at the IEP or the ingress protection junction box, or it representing their protection to numbers. One representing the protection against liquids and the other representing the protection against mechanical stress. So you will find that two numbers, 676.7 is a very high IB or ingress protection. This value, it means that this junction box is well-protected against water coming from rain, e.g. and protected against the mechanical stress. Now you have to know that most of the photovoltaic junction books have diets, which is, as we said before, it's a bypass lights. Now, bypass diodes. We said that it is forming as a chunk pause to allow current to bypass the faulty or underperforming module. So if zeros are faulty inside that part of the pattern or as shading effect, it will bypass this pattern or this part of the panel. Okay. There is another type of diodes which is found where inside that charger controller, which we are going to discuss, this diet or the blocking died prevents the current from flowing back, from flowing back through the string. This is a charging the battery at night or other time zones as solar panels or not work. So in the end, it prevented the power flow from the batteries to the solar. Okay. Okay, So let's see closely how it looks like. So this shape here is similar to this one. So you can see we have the, what is this diets, the bypass diodes. Now if we look at this figure which we have discussed before, you can see we have how many how many lights? 12.3, right? If you look here, we have 12.3. Now we can see that here we have this one and this one. Each diode takes two rows of cells, 1.2 and 3.4566 source, okay? So funds that we have one line here, second line. Whereas the third one, we have one here, one here, and one here, and one here. Okay? So if you look carefully here, you can see that Zafar diodes for a slight connectors between two bus bars. Second diode connected between this bus bar and this bar here. This dye connects between two bus bars. So to make it more clear, okay, If we look, we have 123, okay, so we have 1.2, 3.4. Okay? So it connects between two bus bars to passports or two lines of string. A string here, here, a cell strings, and here two strings. String here means a string of salts. Okay? So you can see we have 12, which is a forest part, and 12 second part here. Then 12 which is a solid part. Okay, So this representing the equivalent of this. And of course, as you can see, we have two terminals by exist this terminal, another terminal here, you can see here we have terminal here and almost automatic. Okay? So I hope this configuration is clear for you. Now. So here, the same idea, you can see we have the bypass diodes. Here. We can say this one is conducting strip or the one which is related to each string. So this tie, e.g. has only two bytes, Which means that we have only something like this. We have our diode legs us and on us all diode like this. Okay? And under them we have group of panels here, and group of panels here. So it dividers that panel into two strings or two lines. Then we have finally is our positive terminal, the negative terminal which goes to the charge controller. And here is the same idea you can see here, you can look at here, you can see it's a poster. As you can see here. This is how it looks like the positive. And the negative. Negative looks like this, or male and the female. Here we can see both deaf. And we said before that bold step is usually the red one and the negative is always the black one. Black one is usually related to the ground. And the poster representing the live part of the electric shock. Okay? So when wiring modulus strings together, which happens in series post of two negative, the voltage is increasing. Wild current stays constant. While wearing multiple modules strings together in parallel. Boast of the ball step negative two negative current is increasing wireless the vault stay connect constant. So if you remember, what does this mean? If you'll remember, we said that in order to connect an order to form a string, what will happen in this case, we are connecting the modules in series and series, which means that we are connecting both negative. And the next one we have posted connected to negative and we have all stuff connected to negative and so on. So we are connecting them in series, positive to negative like this, which increases the total voltage but keeping the current constant. And we said that when we have strings and we would like to form an array which is group of strings parallel to each other. We need to connect to bolster was posted like this and the negative was negative. Then we take this terminal and this terminal to have our paths. That idea of connecting to boast of the ball step negative to negative. So as if they are not as f, z are in parallel. Now let's see how does a PV panel junction box looks alike. Okay, so if we run this one like this, we go like this. If you open czar junction box off any panel, any PV panel, you will find that here. By exist. You will find that we have 12.3 diodes, right? We have 123 lights. Usually will find here to 10 min. You can see this here and here. Okay? So you can see that here, this one usually is a positive and this one is negative. How can I know this? Okay? So this circuit is similar to the one which we discussed before. We had three diodes and three strings. So in this figure you can see we have the terminals here. But which one is positive and which one is an act? So how can I know this using the womb? It will do something like this. You will go here and take the red one which are presenting as a pollster, and the black one which representing Xanax. So we will start adding this to this point. And the connecting this on this point, like this. You can see that the voltage here is 17.42 volt. It means that this is actually supposed to and this one is an act. Okay? We are connecting correctly, okay? So if this value is negative, it means that we have the reverse. It means that this one is that both f and this one is an act. So the red one is connected to the ball step and black one connected to negative. If we don't that connection correctly, then you will find it here. Bolster. If the connection is wrong, you will find the negative. Okay? So as you can see, we're looking at here we have bold step. And so what we are going to do, we are going to add two indicators to help us know or remember that. This one is a boast of one and the other one is zero or the ground one or negative term. Then what is the next step, Zeno album to remove this. And then we are going to add our wires. So as you can see here, like this, we have the two wires like this. Then we'll start connecting that red one with the red one and the black one was black one. You can see like this. Keep it in place by EXOS. Okay? Um, they the red one and put it here like this. Okay, so we will first Like this. Yes, we will see this one in the next lesson. Don't worry. So let's move a little bit like this. You can see we removed as a sport. Then we connected it to the red line so that we can fix it here. Like this. As you can see. Then why are we going to do the same thing for the ground one or the black one? So as you can see, we have this to fix it. We have the positive and negative. Then we close that. You will like this, and then we are completely die. Okay? So as you can see here, here, as you can see, connected here and connected here. So in this lesson, we learned about with BV junction box, and we learned about with the wiring of junction box. 15. Solar Wires and Cables Installation Process: Hi and welcome everyone to this lesson in our course for solar energy. This lesson we will discuss solar cables and wires used in connecting the panels. So here when we are installing our PV panels, you have to make sure of some instructions. The first one you have to avoid that actually between the positive and a negative terminal of the panel. Or to be more specific, avoid forming a short circuit between the two terminals because it may lead to damage of the pattern due to a very high short-circuit current. Second point is that you should reduce or reduce the distance between the panels and the charge controller or the inverter to reduce the losses. So you have to understand that this system, in the end we will have two terminals of positive and negative representing the output power or output voltage and the current of the whole system. When we are, what's the next step? We are taking this and going to the charge controller. Okay, then from a charge controller we are, we are going to connect to the batteries. And then from here we'll go to the inverse. So we have to make sure that the distance between panels and charge controller also invert and must be reduced. Okay? So why? Because when the distance is reduced, distance reduced. It means that the resistance will be reduced. Resistance provided by wires. It means that the power losses in the system will be reduced. Okay? That's why we try to keep the charge controller and or inverter as close to the panel, as close as possible to the panel. Also, we have to allow space between panels to reduce the wind effect. So when we have strong wind, this can mail it to leaving the panel from this location. So our wind here, we will allow when wind comes here like this, we will allow it to pass through this smallest space. You can see there is a very small space between balance so we can allow the wind to pass through it. Okay? Also, we need to avoid obstacles and shadow in front of cells in order to avoid the shading effect as we remember or as we discussed before. Finally, we need to, you can see here is that the enclosure of the system here, this enclosure at which we install our BV been similar to this one. This enclosure. You can see that we need to do the sourcing system. We need to connect this one to that ground. Do and arcing for this enclosure and this part, this enclosure, and for all the fix-it components of the PV panel, why is this? In order to discharge any charges on that system? So that to avoid any electric shock, we are going to use a BB structure, which is made of aluminium. It is irresistible to rust. So we use this one made of aluminum. So we discussed the Nile, some instructions about installation of PV systems. We have to understand that there are two definitions. One which is called wires and the other is called cables. So first, the wire. The wire is a conductive material and made copper or aluminum wire, copper and aluminum because most of them have high conductivity. Ok. So as an example of X0, Y0, you can see this one is considered as a wire. A wire which consisting of group of conductors, another wire consisting of a group of conductors, and so on. If you look at here, we have a wire, this one, and this one is also aware. And this one is also aware. Okay? One wire contains, consisting of group of conductors inside it. Okay? Now we have to understand that wire representing one cooler, one cool, or one terminal. So as you can see here in these images, we can say is that the red one is a positive. One. Wire represents things are positive terminal. Another y representing the negative term. And so on. And another wire which can be all saying, which is usually green and yellow, combination of green and yellow. So it is usually representing one core. One core. Now what is k with k, What is a group of two or more different wires? Instead of having just one Wildlife Service or one-one like this, we have a group of wires. This, you can see the scale bar consisting of a group of wires, 1234 and so on. So group of wires together in one, in one bundle surrounded by an insulating material. This, in this case, we wouldn't have k1. So k1 is a group of wires, or sometimes we call the cables that at consisting of several course. It is multi-core. So if you remember in the previous lesson when we discussed open circuit and short circuit test of the PV valid. If you remember that we had one black bundle inside it, it had three wires. One had two wires, which is a red one and the black one. And the other one had three wires, which is the green one. If you remember, we said that in that video, we said that if we measure the voltage between the red one end or between a red one and this black one, we will have the total voltage and between green and the ground, we will have hovels of voltage, if you remember. So a cable has different diameter depending on the number of conductors inside it. So a wire is considered as a single core, e.g. one phase or one terminal. However, the cable is a group of goals or wires. So usually if you remember, in electrical system we have a three-phase system. Okay? So sometimes we have a cable, larger cable inside it, we have three cores, 12.3. Now this three cores, each color representing one phase, e.g. a, and B and C as a three-phase score of a cable. Okay? Now, each one of these is considered an outlier if it is alone, like this. Okay? So as you can see, this is an example of solar cables. This is how it looks like. We have the red, which is really representing the positive and the black representing the negative terminal. Okay? Now this is also the front cables with different millimeter square or different area. You can see here one C, which means one core, multiplied by six square millimeter squared or millimeters squared. So this one has an area of 6 mm squared. And of course, area is important in selecting the cable because it representing how much is a cable will carry, the current, how much current it will carry. So finds that the solar cable is a cable time, especially designed to be used in photovoltaic power systems. This cables are high ultraviolet radiation resistant and over it's in a wide range of ambient temperature. It can start, it can operate from negative 40 Celsius degree, Celsius degree and up 200 Celsius degree. So from negative 40 Celsius degree and more to, up to more than 100 Celsius degree because it is inside. Inside it is. Suppose the tools are ultraviolet and exposed to the high temperature of the sun. Now, these cables are also suitable for permanent, I would do long-term use because they are available in the sun. As they are exposed to the sun through hours a day. This cables are expected to beam as expected period for this cable is 30 to 40 years. Under normal conditions. You will find that the cable itself or the solar cables, that cheese of the cable, cheese of the cable is halogen free. Now why is this? Because at help us to help us scale to become highly flame retardant, which means that it is protect us against or it can withstand the fire cases. Okay. So of course is a halogen free cables also are not toxic and does not have any grooves, have gases. Okay, so any corrosive gas are not released in fire because it is harmful to humans. And okay, that's why we use, we use the halogen free cheese. As an example. If you open a website, any website and social false color cables. As an example, this company solar cable of 10 mm squared CSA, which is a cross sectional area, or the area of the k. So this cable is, has an area of ten millimeter square. And the can was a standard current, dc current up to 98 and bear. And the flame retardant and halogen free. Okay, it can operate in temperature from negative 40 Celsius degree up to 90 Celsius degree. Okay? Now if you look at the specs of this cable, you will find that it is fire behavior, it is flame retardant. It means that it can withstand the high temperature off during fire and halogen free because it does not release any harmful gases after burning out. Finally, here we have the cross sectional area ten millimeter squared. And the current ratings are rated current of this cable is a maximum current. It can with stand in normal conditions 98 and bears the minimum and the maximum rating conditions. You can see negative 40 Celsius degree and the 90 Celsius degree. And the cheese colored the color of the cable itself. You can see black color. Ends of the diameter of the cable itself is 7.2 mm squared. So if users to multiply pi over 47.2 square, if you multiple get the area which is equal to the area over four D square, you will get ten millimeter squared. Okay? Now you will find that solar cable type. It is a solar PV cables shape it is a single core cable, one representing one core or one phase. And this one met the standards of IEC, this different standards of IEC standards. And this is the operating temperature range. Here we have the voltage rating, which is 1,500 volt, which is the maximum voltage that this cable can with stand. Okay? Now we have to see, now like this, if we have balanced, we discussed this several times and in different ways. We said before that we have for each panel, we have positive terminal and the negative terminal for each of these panels. If I would like to connect them in series, I will connect to the negative was posted and take the other two terminals if I would like to connect to them in Paris and bolster was positive and the negative was negative. Then we take the two terminals of the positive and negative. Now the question is, how can I do this? How can I connect them together? And what, what I need to do in order to do this function. Okay? So before we do this, we will have just a small discussion about the standard color code for cables. Okay, So this will help you to understand that different colors used in different systems. E.g. if you have a three-phase system which is not related to as a PV system. A three-phase system in general, you will find that we have the color or a color of p and the color of c ands a neutron. Ok? Now if we have a single-phase system which has live part ands are neutral apart or Tsar live cable or core, and neutral cable or core. Okay? So we have DC, which has a positive terminal and the negative terminal, similar to our PV system. And the conductor or the protective earth color. And you'll find the user reference which is used for each of these colors. Okay? Find the ears different phases, e.g. if you are in the European Union, you will find that phase a is prowling, be Black, Sea gray than neutral light blue. For active and the neutron black or brown and the light blue. And you will find the IRR for this dash. What does this mean? It means there is no recommendation given signs are Francais, so the force of protective earth's most likely in all of these different regions, you can see European Union, United States, Australia, China, Japan, Japan, Russia, South Africa. All of these. You will find that the protective Earth is almost assembler. Green, yellow. Okay? You can still find green yellow cable is usually usually representing the arcing system. You will also find there some nodes here which you can see. So you can just take a screenshot of this and save it to your PC. Or if you have the slides, you can get back to it if you would like to see or know the color of any cable. Okay, now for our system or the BV system, you can see is that we are talking about the DC system. So you will see that here it's a positive. And the negative. You can see that the posterior is what color red and then negative what color? Black? This is a new new new Zealand and Australia. Okay. So this colors is the one which I'm discussing in this course. You can see we have used the rent for the live part and the black for the negative part, or the ball step and neck. As there are other countries, such as Russia as a use brown and gray. So what are the tools we are going to use to connect two panels or more together. Okay? So first we have the solar cable cutter. What does this function or what is the function of this? It is used to cut up out of the wire. Remember that we have a large and our larger long wire. So we are going to just take a part of it. So how can I cut just a part of it using this tool which is called SAS solar cables. Okay. Second part is a solar cable stripper. What does it do? It simply removes the insulation layer. Okay. In order to add contacts or that pen of the clamp or the MFA for connector. We will see all of this, don't worry. We have the MC4 solar crimping crimping tool. It is used for cables or solar panel. Wires from 2.5 million to 6 mm square solar panel BBQ. You'll see each one of these representing different cross sectional area. Okay? So this, you will find that what is the function of all of this? It is used in the end, connected between two panels. So let's see first is that solar cables travel. What do we do? We simply we add our cable. You can see here 141210 millimeter squared or 1 mm square, 14 mm squared. So according to that cross-sectional area of the cable, we will put a cable here, e.g. as you can see. And then we will close on it by exist. And then after this, we will just pull this one away. So in the end you will be able to what? To remove the installation of the cable. Okay, So what we are going to do with this, we just need to remove the insulation. So how it looks alike when it is in motion, you will feel spine here at some animations here, e.g. you can see like this. Okay, so we add that tool, that solar cables triple. And then you will see that when we compress or by compressing here, you will find that the installation itself is removed. Okay, like this. So I can just remove this installation part. And then I'm going to connect it. Added adder can contact to it. Okay, so we will see another one here. You can see we add a cable and Lexis, boom, very fast, okay, likes us. So we remove the insulating material. Another one here you can see we add that cable like this. Okay? Here. Okay. So you can see here at the beginning, like this, we add it here. Then I'm okay like this according to the dimensions and when we compress, you will find that the installation is removed. Then we will remove another installation like this. Okay, So we have here two insulating parts for this cable. We have a two insulating board. One which is a white 1.1, which is a small cables or the small wires. So that this tool had two locations. One to remove that white insulation and the other one, use the to remove that insulating material of each line. Now we have also the MAC for solar crimping tool. What is the function of this? You will find that assembly I'm going to add here is a pen like this, this pen or the contact. Then I'm going to compress using this crimping tool to hold a trust in place without compromising too much. Then we are going to add our wire. So we have, remember that we had the wire without insulating materials. So I'm going to add this part connected here, like this. Then I'm going to compress using this crimping tool so that this part will be added to the wire itself. Then we are going to make Zach grim. And then we will have something like this. Okay. Then I'm going to add it to that male or female. Then I'm going to rotate and we will have finally, the male or female we would like to use. Okay, So in general, here is the summary for the steps and we will see a video, don't worry, we'll see a video. So we have the stripping part which removes the insulating material. So we'll have something like this. Okay, then I'm going to connect as a sport added here and connect to my own wire, then compress a little bit, just to compress a little bit so that it will be fixed it to this part of the wires. Then I'm going to insert it to MAC for, remember we said before that we use MSE for male and all female to connect it between two panels. So I'm going to open this part is in insert as this one and then sold as this one and start rotating to keep it in place. Then we're going to tie it in as a tightens or MSE for male and the female using these tools. Okay. So we have seen now the steps required to form a male or a female MSE for male and the female, which you are going to use to connect two panels together. So what we are going to do now we are going to see a video to understand the idea. So let's look at the video here. You'll see that this is what we would like to do in the end we have male and female, or both positive and negative. And we would like to connect them together. So we have a cable here, which we would like to connect it to the MAC for connector, and another cable to the MSE for connector. That's what we would like to achieve. So let's see how we are going to do this. Okay? So if we go here, you will see what to do. We have the cable. This is a solar cutter which will help to cut just a part of the k well, as we would like. So as you can see, we cut using this tool. So we can have any lambs in the length of the cable and just take a part of it using the solar. Okay. Then we're going to use that. So a lot of stripper tool, you can see that here we have 2.4, 4.6. You can see here millimeter squared, 2,154.6 mm squared. So depending on the cross-sectional area of the solar cable, I'm going to put it inside which one of these holes. So as you can see, we bought a tooth like this. And then when I compress, you will find that the insulating material is removed. So if we get back here like this, again, you can see when I compress, that insulating material is removed. Okay. Now, what does the next steps, and I'm going to add the contact. You can see here two types, two types of contexts depending on the rim of the MSE for connected. Okay. So you can see we added first here the contact. Them are going to add the cable like this. Then we will compress like this. So we'll see what will happen in this case. You will find that the cable ends up connector became one part. Now I'm going to add it to the MSE for male and the female like this, watered like this. Then remove this one, rotate and remove them, put it in slide like this, then rotate again. Like this, keeps rotating. Okay. So we will tighten it using these tools exist in order to have our male and the female typing correctly. So it will have in the end one wire connecting to a male, which are presenting that negative terminal. And another one connecting to that mail, which are represented as opposed to the terminal. So we can now connect them together as we would like. Okay? Okay, so here we learned about with the solar cables connection. Okay? So here's an example. So we have our B and a junction here for this panel, and another being a junction here. Let's use Zach connector here. One being a junction here, another one here. Now we have what we would like to do. We would like to connect them in what? In series. In series. So if you remember that, if I would like to connect to them in an OT in series in parallel. This configuration is for parallel. So what I need, I would like to connect the pollster was positive and the negative was negative. Then we take the positive and we take the negative. Okay? So we'll find that like this. If you look here, we have both staff and Donald's or bolster sensors. You are male. Most of them are males, not male and the female, female representing the negative, the male part representing Zappos stuff. So that we have here, if I would like to connect them better, we have two males. So we cannot connect them together. So we'll use, will use something which is called the MAC for multi-branch connected. We will put the first one here and one here. So in this case they are connected together. We will have final balls Tifton. Then for the negative, we will connect a negative here, and it's also negative here to the also multi-branch connector, we will have a falling non-negative. So this is in the case of parallel connection. Now in the series connection, in the series connection, you can see that in series we connect both of us negative. Now boast of year, we took a cable here and we use that crimping tool, all of our tools to finally get a male and the force and negative when we did the same process to get a female. Now simply we will connect as a male with the female here. Now, then we will have two other terminals. One which is a pollster, and one-fourth, which is negative, which are representing the positive and the negative of the whole system. This connection is series connection. Okay? So in this lesson, we learned more about the PAV installation process, some instructions, the solar cables and wires. And how can we connect as a two panels or more together? Okay. 16. PV String Maximum Voltage: Hey everyone. In this lesson, we will discuss the BV string, maximum voltage. So you have to know that when we are installing our PV panel, you have to make sure that our voltage does not exceed a certain value. So what does this value? This value is dependent on the contrary, good or manufacturer itself. So as we will see here, now, if we look at this module type which we have discussed before as this one, you will see that here we have a very important parameter, which is a maximum system voltage. If you remember, we said before 600 volt DC. So what does this mean? It means that when we are connecting these modules together, you can see in order to form a string like this, remember that when we are connecting them in series, we are increasing the voltage. Since there's a panels are connected in series. So we have to make sure that the total voltage of all of these panels have V1, V2, and until VN. So the summation of all of these voltages from v1 to vn, summation of all of these volts is less than or equal to 600 v. So we have to make sure that the system voltage of string does not exceed 600 volt. So here you have to know that in the United States, e.g. for the residential and commercial PV systems, it is rated up to 600 volt. So it is important to make sure that the PV array is configured so that this X hundred volt rating is not exceeded or according to that manufacturer here. Okay? So according to the load or according to the module itself. Now, you have to know that what causes the voltage to increase. So if you remember that we said before that the temperature itself, when the temperature increases, what will happen to the system? The power was assaulted decreasing and the voltage will also decrease, right? However, something which will happen in the reverse case, if we have the temperature which is at 25 degree is a standard test, the condition temperature, STC, condition temperature, which is equivalent to V open circuit, whereas I V open circuit with V open circuit of 7.5 volt. Now, if the temperature decreases below that 25 citizens degree, what will happen to the voltage? Voltage will start increasing. So we have to make sure that at the lowest expected ambient temperature in the site or in the location at the lowest temperature, e.g. let's say that lowest temperature is 1 c degree. So we have to make sure that at 1 c degree, the voltage of this string does not exceed 600 v. Because as we know that when the temperature decreases, the voltage will increase. So we have to make sure that the voltage here does not exceed 600 v. Okay? So the B from the tool manufacturer provides a temperature coefficient which we have discussed before as temperature coefficient of the open-circuit, denoted by this T K V open circuit, TK is the temperature coefficient V open circuit. It must be used in the calculation of this voltage. So as an example, you can see here that temperature coefficient here is one temperature coefficient of V open circuit. This coefficient is the one which I'm talking about, T K V open circuit. This temperature coefficient, which is equal to negative 0.3 per cent for each lesions degree. So what does this mean? It means that for each temperature, for each 1, c degree increase beyond is a 25 citizens degree each one. So this has degree. Our voltage will decrease by negative 0.3%. Okay? But what if our temperature decreases? So for each temperature equal one. So this are degree h decrease in temperature, delta T. Each decrease in temperature when lead to an increase in voltage by plus 0.3 per cent for each Celsius degree. So this value, negative 0.3 for each increase in temperature. For each increase, voltage decreases by negative 0.3%. For each decrease in temperature, it will be plus 0.3% increase in the voltage. Will find that the coefficient tells us how much is joules voltage will increase, bear citizens degree below the standard test condition of 25 citizens degree. So you have to know that sometimes the manufacturer itself provide the Zan them Richard coefficient in the form of how many volts bear solutions degree, or how many millivolts for Silesia degree, or as a percentage per Celsius degree, as you can see here. Okay? So what are we going to do? How can we know this? First? You, if you have e.g. if we have this string, ends our module, each module is string. Each module, each one pattern has a temperature coefficient of negative 0.12 volt per series as degree. What does this mean? It means that for each, for each decrease in temperature by 1 c degree, our voltage would increase by plus 0.12. Okay? Because here, negative, what does mean? Negative means a decrease pair what Bear increase, decrease in voltage, bear increase or decrease in temperature leads to increase in voltage, okay, as they are opposite to each other. Okay. So what does this mean? It means that for each 1 c degree below 25 citizens degree Zemo dual voltage will increase by 0.12 volt. E.g. if you have on what you always given in percentage versus religious degree, we will multiply this coefficient, percentage, how many percentage of boys or open-circuit voltage to get, how much we will increase. So as an example, if we have a module with an open-circuit voltage of 6.29 volt and the temperature coefficient is negative 0.36% versus religious degree. So it means that for each 1 c degree for each decrease in Celsius degree for each one, for each degree below 25 citizens degree, we will have a voltage of what? Of 6.29 multiplied by 0.360, 0.368 per cent. Now we have to know that all 0.36 per cent equal to 0.36 and divided by 100, okay? Because we have a percentage, okay? So this divided by 100, we will move this one to the side 12. So we'll have 0.0, so we'll have 0.20, 0.00360, 0.000036. Okay? So this means that we will have, our voltage will be like this. V open circuit in general is equal to 6.29, which is the current, the voltage at 25 citizens degree plus 0.133 volt multiplied by delta t. And delta t here representing water representing 25 Celsius degree minus the new temperature. So if we, our new temperature is 24 degrees, the difference will be one. So our voltage will be 36.9 plus 0.133. Positive voltage increase when temperature decrease. However, if we have at 25 Celsius degree of this one is 25 citizens degree, then the difference is zero. So this part will be equal to zero. So our voltage will be 6.9. Okay? So once we do this calculation, we must have determined the lowest expected ambient temperature. You can do that calculation and according to a number of modules and installed in series, you will get the maximum voltage ends up corresponding temperature. Or to be more specific, or the correct way is that we already know the lowest temperature in allocation. We already know the lowest temperature in a location. So from this data, we will already know. We will be able to know how many modules, maximum number of modules that will be installed in series, as you will see in the next slide. So here's an example to understand this idea. Let's say we have a string which uses like this one, a string which uses our modules with V open circuit equal to 76.29 v. So 6.29 volt. And the temperature coefficient is negative 0.36 per cent per Celsius degree. And we are located in allocation with an extreme minimum temperature of negative 23 reasons degree. So this is the lowest temperature in the location. Okay? So Forest according to the lowest temperature, Let's see what will happen to the open-circuit voltage of one module. So simply like this, you will find that the drop in temperature with respect to the STC conditions, you will find that here we have 25 citizens degree, which is temperature at STC, which is equivalent to voltage open circuit of 36.9 minus then you temperature, which is negative 23 solicitors degree. So we'll find that the difference in temperature, or that drop in the temperature is 48 Celsius degrees or Celsius degrees. So 48 Celsius degrees. What does this mean? Or what is the value of the voltage corresponding to this Celsius degree? You will find that here like this, h temperature drop, each 1 c degree drop is an equivalent to n increases the voltage by this value. You can see we have 0.36%, 6%, which is 0.3 6/100 multiplied by the open circuit voltage, which is 0.13 volt. So for each 1 c degree, decrease in, by 1 c degree, we will have an increase in the voltage apply 0.133. And as you can see, we are dropping by how much we are dropping by 48 Celsius degrees. So you will see like this, the total BV voltage or the total increase in the PV voltage is will be equal to 48 Celsius degrees 0.1, 73 volt will give us 6.38 volt. So our panel, due to the drop, due to the drop in temperature from 25 citizens to a negative 23 degree. We will add this voltage to that, so 6.9. Ok. So in this case, the maximum voltage for each one module, maximum open-circuit voltage of one module is 43.28 volt. So each one of these maximum open circuit at the worst conditions, we will have 43.28. Okay? So what we are going to do now, we have to make sure that when we are connecting several modules in series, we shall not be less than or equal to 600 v. So this is a question here. What is the number of modules in series that will achieve this condition? So e.g. if you are connecting at well-formed goals in zeros, 12 modules, we will have the total voltage, total, maximum, total open-circuit voltage of the system will be that well volt or not, that 12-volt, the number of modules, which is 12, 12 joules, multiplied by the open circuit voltage adds a negative 2.3. So easier Celsius degree, which is 43.28 volt. So if we multiply this two values together, we will get 519.4 volt. Now, as you can see that this value, if we have 12 0 modules in series, adds a worst condition. Or at extreme minimum temperature, we will have an open-circuit voltage of 519, which is less than 600. So it is acceptable case. We can connect 12 modules in series. It is acceptable why? Because it produces less than 600 volt at the extreme conditions. However, if we assume 14 modules, what will happen? 14 modules, it means that the system voltage will be 14, which is the number of modules multiplied by four is 3.28. You can find that it gives us 605.29 volt, which is what, which is, which is greater than the maximum system voltage of 600 volt. It is higher than the maximum system voltage. So in this case, this one will be rejected because the 600 volt limit is exceeded. So we cannot connect 14 modules in series. Our maximum number of modules in series will be 12. Okay? So the question is, how can we know the extreme minimum temperature of allocation? There are several ways to do this. You can search for it to find the minimum temperature in allocation. For me, we can use this website. This website is called solar ABC's dot org. If you go to this website, you will find as solar reference map. What does this do? You can find here locations in the US. When you select any location in the US, e.g. here, you will find that this website or this map, we'll give you the extreme or the minimum temperature in allocation zero Celsius degrees. So I can use this one as the minimum temperature. So delta t, which is the difference between the STC temperature and minimum temperature, will be equal to 25 Celsius degree minus zero Celsius degree, which will give us a difference of 25 Celsius degrees. So I'm going to multiply my own Walters 25, 25, multiply it by that percentage or the increase in voltage. You can find also using the global solar outlaws and other methods, you can get this extreme minimum temperature. Okay? So in this lesson, we discussed the maximum voltage of BV system. And we understand now why it is important to do this because we need it in our design. So when we are designing our PV panel, we have to make sure that the modules which you are connecting in series so not exceed the maximum voltage at extreme minimum conditions. Okay? 17. Important Definitions in the Global Solar Atlas: Hey, everyone. In this video, we will talk about the global solar atlas and we will have some important definitions regarding it. Let's start. Before we go to understanding the definitions regarding the global solar atlas, we need to understand the difference between landscape and portrait panels. This is a very important definition or a very important difference. If you remember when we talked a pot BV rows, we had a BV row like this and another BV row like this, contains consisting of group of panels beside each other, similar here in this row, like this. If you remember that we said there is a space between them right, Now, we said that this is the width of the panel that we use in identifying the distance between the two roles. Now, the panels itself can be installed in two different ways. They can be installed in the form of a portrait like this. You can see this is what we call portrait, one panel besides the others, and the landscape is installed like this. This is a vertical installation called portrait and the horizontal installation called landscape. So this in installation depends on the area itself in which you are installing the PV panels. If it is like this, for example, long area like this, then which one you are going to use? I'm going to use the portrait like this like this in order to make the panel fill this large or long area. If for example, it is horizontal like this, You can install the panel like this in the form of landscape. It depends on the area in which you are installing the BV panel. This is a difference between portrait and landscape because you will find this in some of the reports regarding the installation of BV panels. Now let's go and understand some definitions regarding the radians or solar radians. This definitions will help us understand some important definitions in the global solar atlas. So we have here our sun, which is providing us with sun rays. Now, we have two types here, or three types of radiance. The types of radiance. Number one, is called the direct radiance. We have sun rays directly falling on the panels. We call this direct radiance because it is coming directly from the sun. Second one called the diffuse radiance. Diffuse radians, which is the sun irradiation or sun rays that are diffused or scattered scattered by the atmosphere, sky, or the clouds. When we have scattering and this scattered rays go to the panel itself, we call this type of radians called the diffuse radiance. Direct coming directly from the sun. Diffuse scattered by the clouds or atmosphere and then going down to the panels. We have direct difus. Now, when you combine, when you compie both of them together, direct difus, you will get the global radians. We have direct diffuse and global radians, which is the submission of diffuse radians and direct radians. That is the first part. Now, let's add more to this definition. Just a little bit more sentence or more one additional word to the sentence itself. So if I say, for example, global, global, horizontal radiance. So what does this mean? Global horizontal radiance. So we know that global radiance means direct plus diffuse. When we add the additional word, which is called horizontal, it means that our panel is completely horizontal like this. As you can see, completely horizontal to the ground. So the global horizontal radiance in the summation of direct sun rays or direct radiance and diffused radians. This is from the sky itself. Direct plus diffuse on a horizontal panel. That's why it's called the global horizontal radiance. Remember this because it is important in V panels. Now, another one, let's say global tilt radiance. Instead of saying horizontal, we say tilt, what does this mean? Instead of having a flat surface or a flat panel, we have a tilted panel with a certain tilted g. Again, global tilted radiance, submission of direct, and diffuse radians, coming from the sun on a fixed tilted angle on a fixed tilted surface. Now, what if I say direct normal irradiance? We say direct radiance, direct irradiance, means sun rays coming directly on the panel. But when I say normal, what I mean by this, it means that the panel itself normal to the sun rays. For example, in this position of the sun, the panel will be like this. Perpendicular, sun rays, perpendicular to the surface itself? If it is in this position, it will be like this perpendicular, and this position like this. So as you can see here, in order to achieve something like this, we have to get a tracking system. Our panels will be always perpendicular to the sun rays. So I hope it's clear right now. Directly coming from the sun diffused, diffused or scattered by atmosphere. Horizontal, when we add word horizontal means that our surface is completely horizontal. When we say tilt, it means it is a tilted with a certain angle, and normal means it is normal or perpendicular to the sun rays. Solar radiance representing how much power from the sun that reaches the surface per unit area, how many what? What per meter square? So in the global solar atlas, which we will talk about, it has four magnitudes related to the solar irradiation, four values or four definitions, number one, the direct normal irradiation. Similar to what DNI or dic normal irradiation, similar to the direct normal irradiance, which is the case on here. This one. It is a part of the solar radiance that direct reaches the surface, P pundicular to the sun. You can see always P pundicar to the sun. Second definition called DIF or diffuse horizontal irradiation, sometimes called DHI, DIF and DI are similar to each other. Diffuse horizontal irradiation. Let's analyze this word. Diffuse irradiation means diffused irradiation going to the panel. And this panel, what its position horizontal. We have a horizontal panel, Diffuse the radion falling on a horizontal panel. That's what it means. You can see that the part of that is scattered by the atmosphere and falls on a surface horizontal to the ground. Then we have the third definition, which is called the global horizontal irradiation. This is the one which we use in the BV system design. It's really important. If you look at the solar global atlas. This one, it includes both the direct normal irradiance and diffuse horizontal radians. It is a submission of DNI and DIF or DNI and the direct normal irradiation and diffuse horizontal irradiation. Submission of these two. Now, there is a very important part here. Which is is that? If you look at DNI, if you go to the website of the global solar atlas and selected any location on RS, and you, for example, look at the DNI, it will say, for example, it will say 5,000. It's a value is 5,000. For example, for any location, DIF, let's say, 2000, if you look at the global horizontal irradiation, it will be, for example, 5,500, like this. This is an actual values of irradiation. But you will see something here which is important is that global horizontal irradiation is a summation of this two, summation of DNI and DIF. So global horizontal irradiation so be 5,000 plus 2000 means 7,000. However, what you will find is that this value is lower than 7,000. It is not the submission of this two. It means that there is a factor, which is remaining one additional factor that we forgot to add. Let me tell you what is this additional factor called the solar nous angle. The global horizontal irradiation should be equal to direct normal irradiation, DNI, multiplied by a certain angle or a cosine of solar nous angle. Plus the diffused horizontal irradiance. We have here this additional part, which makes them not directly the submission. There's just a small difference here. Okay, what is the solar Zenius angle? What is this exactly? Let's go here and understand. So we have here our location. Let's say, for example, this is our panels here. Now, the vertical vertical, which is perpendicular to the surface, the perpendicular or the vertical on the surface called the Zenius. And we have here our sun, as you can see here. The sun raise or irradiation going directly to the location like this. Now, the angle angle between the zenus and the irradiation or the sun raise calls the zenus angle. This is the one which I'm talking about between zenus and sun raise. Now, let's talk about it in a different way. Remember that when we talked about the sun short in the lesson of the distance between BV rows, we said that the angle between the angle between sun irradiation and the ground and the ground called the altitude angle or called the solar elevation angle or called the shading or the shadow angle. All of this representing one thing, which is the altitude angle. This angle, which we use in the selection of the distance between two B V rows. Now, what you will see from this figure is that the submission of the Zenius angle and altitude angle is equal to 90 degrees. You can see here 90 degrees. We say that the Zenius angle is the complement of altitude angle. It means that Zenius angle is equal to 90, minus solar elevation angle or the solar altitude angle, and as you can see in this figure. This is the relation between the solar zenous angle is the angle between the sun rays and the vertical direction, which is the ens here. Second part, it is considered also as a complement to the solar altitude or the solar elevation, which is the altitude angle or elevation angle between the sun rays and the horizontal plane here. This angle. Now, you will find something which is important. The higher values of DIF over GHI represent a higher occurrence of clouds, higher atmospheric pollution, or a higher water able content. So what does this even mean? DIF over GHI. So if we get back here, DIF means diffuse horizontal irradiation, or the diffusion amount. The amount of sun rays diffused, with respect to I, which is the total irradiation. So if you think about it, when the ratio between the amount of diffusion, with respect to the global, which is the total irradiation. Total irradiation. When this diffusion becomes very large, or this ratio becomes very large, with respect to the total irradiation. What do you think about this? It means that the location we have here have higher occurrence of clouds. We have lots of clouds that cause scattering of the irradiation. Also, we have higher atmospheric pollution or higher water content. All of this lead to scattering of the irradiation or causes diffusion or diffuse irradiation. Now, we discussed the three definitions, DIF. We discussed also the GOI. We also discussed the direct normal irradiation. All of these definitions were three definitions. The last definition is called the global tilted irradiation at optimum ng. Now, similar to the global irradiation, which is a submission of direct. However, tilted, the surface itself is stilted at the optimum n. So we have here like this panel stilted at a certain angle. Sta. This angle is the optimum tilt ng. The amount of irradiation falling on it. In this case, will be equal to, the amount of radiation falling on it will be equal to the summation of direct and diffuse. Or what we say here, the global tilted irradiation at optimum g. It is the maximum amount of solar radiation that can be received at the ground at optimum ng. Okay. Now, let's discuss another thing which you will find. Now, when we talk pot panels, we say that we talk pot panels in the form of kilowatt peak. So when we have a PV system, we say that this PV system is, for example, ten kilowatt peak, five kilowatt peak, ten kilowatt peak, 15 kilowatt peak, and so on. So this is a measurement of the maximum power, maximum amount of power that this panel will give, for example, at noon on a sunny day. At the at the time with which we have the highest irradiation. So when we say, for example, if we have 250 what panel, this value, this amount of power is at STC conditions, which is irradiation of one than what perimeter square, 25 Celsius degrees, and 1.5 air mass, as we discussed in the course, lots of times. We have 250 watts. If I combine four of them, we will get 1 kilowatt peak. Won't kill what peak. So this is what does this mean? It means that the maximum power that our BV system can give at noon on a sunny day. That's what mean P kill what peak. Now, if you remember from the STC conditions, when we said 1,000 perimeter square, this number is actually equivalent to the global horizontal irradiation. This is actually related to each other. Okay? Okay. Now, let's continue. So the globe, the kilowatt peak of a domestic system will vary depending on how much a customer wants to spend and the roof area available to accummoate. So what does this mean? So how much kilowatt I can provide depends on the budget of the customer itself, how much money does the customer have? Second thing is that how how much area is available to install our PV panels. So let's say you have a certain area, depends on this area, we can install a certain amount of kilowatt peak. Okay? Now, there is another definition that you will also find in the global solar atlas, which is called the BV potential. This one measured in Kilwa pa Kilwa peak. What does this mean? How much Kilwa can this BV system produce P one kat peak. What does this mean? Let's say, for example, you installed a BV system with a 1 kilowatt peak. You installed this system, let's say in a country like Egypt, and at the same time, you installed it in Poland, for example. Now, you will find that, for example, that the energy produced in one day in Egypt would be five kilo hour peer day. In Poland, for example, you will find, let's say, 2.9 kilowatt hour per day. This is a better location to install our PV panels compared to Poland. You will find that in the global solar atlas, you will find for every location, we have kilowatt hour pair kilowatt peak. The higher this number, the more energy can be produced in location compared to another one. So what does this number depend on? This number depends on how many hours or how many sun hours available in this location. For example, in Egypt, we have 5 hours at which we will have sun that will give us the maximum power from the BV panels. 5 hours during the day. For example, Europe, for example, in a country like Poland, it will be, let's say 2.9 hours. So the more hours we have, the more energy that can be produced from this system. Because in the end, you will find that when we go to the design procedure, you'll find that the amount of sun hours will affect the sizing of the system. It will change even the cost of the system. Now, using the global solar atlas, you can find the irradiation of allocation, all of the four magnitudes that we talked about. You will find the required lty angle, the optimum angle without any method. You'll also find the temperature using the global solar atlas. We will go to these two websites that you will find in the course of slides. You can go to them by downloading those slides and go to these two links, and we will see what are we going to do? When you go to the Globalss, you will have something like this. Let's go in the next lesson and see, what can we do with the global solar atlas? 18. Global Solar Atlas PV Simulation: Hey, everyone. Let's start talking at the global solar Atlas. So when you open the website, global solar atlas dot flash map. What you can see is a very large map here, what you can see for different regions in the world. Let's say, for example, you would like to choose any part. I will choose my own country, Egypt, and the region Cairo, like this. I would select any point like this. What you can see first is Cairo, which is a selection region, and the first part, which is a latitude and longitude of that location. If you go down here, we will find the data of this location. For example, the first one, which is a specific foot voltage power output, which is a ratio between kilowatt hour per kilowatt peak. Let's convert this into instead of per real, let's make it per day. What does this mean? It means that if you are installing 1 kilowatt peak V system, you will be able to get energy from it around 4.9 to it, kilowatt hour. Now, this number can change from one region to another. Let's say, for example, if we go here to any Eurobean country, let's say here. An random one. If you look at the specific foot will take power, 3.186, which is lower than Egypt. If we go here like this, 2.9. Depending on the region, the amount of power which can be generated can change. The higher this number, the better the generated amount of energy per day. Then you have here is the direct normal irradiation, DNI and global horizontal irradiation, diffuse horizontal irradiation and the global tilted irradiation at optimum g. All of these four definitions which we have discussed in the lessons of the definitions of the global solar atlas. If you don't remember it, go to these lessons. Okay. Now, for this area or this location, you will see that the global solar atlas told you that the optimum delta angle of the BV modules is 26 degrees. This is the optimum angle calculated by this program or this simulation. And 180, what does 180 mean? This one is the Asmus angle. Since our country here, Egypt is in the northern hemisphere, we have to face our panels to the South, which is equivalent to 180 degrees of Asmus here the air temperature of the surrounding temperature of the location itself, and the elevation of the location. Now, another thing here you will find is that the global tilted irradiation at optimum angle. Now, this is representing how many kilowatt hour per meter square and the global horizontal irradiation. You have to know that GI and gt R are used to get the peak sun hours. What does peak son hours mean? It means that the number of hours in which we will have irradiation of 1,000 or higher, 1,000 permere square. If we just do like this, and just type something here. Here, the peaks some hours peak some hours, s hours in one day in which we have irradiation of 1,000 permere square or higher. This is equivalent to what is equivalent to the STC condition of the irradiation. STC 1,000 permere square, 25 cs degrees and 1.5 mass. Now, the GHI here, for example, GI, its value is equal to 5.76 1 kilowatt hour per meter square. This 11000 is equivalent to 1 kilowatt/meter square. Now, if you look at this one and this one, 1 kilowatt/meter square, 5.76 1 kilowatt hour. This means that this value g is equal to b hours. Multiplied by 1 kilowatt/meter square. This number 5.761, representing how many hours or the pix on hours per day. But you have to remember something which is important. Here, global horizontal irradiation, representing the peak sun hours here for a panel installed horizontally, Delta angle equal to zero. The amount of radiation falling on a horizontal plane. However, if you are using a telta angle, let's say 26 degrees, you'll find that this value is the one which you should use in getting the number of sun hours. The number of sun hours should be 6.3 hours. You should have used this one if you already know the telta angle that you are going to install. If you don't know yet the delta angle, then you can use the GI as the peak sun hours. Y Paksun hours is important because they are used in the sizing of the B system. When we reach the lesson of the design of BV system, you'll find that we will need the Peak sun hours. So you can use GI or GTI. However, GTI is more accurate representation of the Peak sun hours. Okay. What are we going to do next? Let's go and select the system. Using the global sol tras, you can choose what system you would like to design, small residential system, medium sized commercial, ground mounted, large scale, floating larger scale. Let's say we are talking about a small residential like this, choose. Then you will find here the configuration of the system. You can see that this system is a small residential. The sms is a 180 degrees, total angle 2060 degrees and the capacity of the system is 1 kilowatt peak. This is the average values generated by the program per day, and you can also make it barrier. Like this. It says that you are going to generate how many megawatt hour per year, 1.727 megawatt hour per year or kilowatt per meter square 2,283.7. Okay. Now, another thing here is that you can change also the PV system. If you click here, you can change the asm like this and put any asthma you would like. You can also change the Delta angle as you would like and the size of the BV system. Now, another thing you can see here is that if you choose small residential, it considered the size as 1 kilowatt peak. For a medium, 100 kilowatt peak. For a ground, such as a large scale grid connected system, 1,000 kilowatt peak, or one mega watt. For a floating on surface of water, you'll find one mega. Depending on the system, the size or the amount of energy wallow change or amount of power wolle change. We have a small residential. Now let's get back here. For something important. Now, remember that when we talked in a lesson about the tilt angle, and we said how can we select the tilt angle of a location? We said that if you are designing based on summer and based on summer, then the tilt angle will be the latitude -15 degrees, 15 degrees. The angle will be 15 degrees in this location. If you are designing based on winter, it will be 45 degrees. Because you are going to take the latitude and add 15 degrees. If you are designing based on autumn or fall, then you are going to choose or spring, then you are going to choose the tilt angle equal to the latitude, which is 30 degrees. Also this depends on the type of the system. If you don't know this, get back to the lesson of the tilt angle. Anyway, let's continue this lesson. So Let's keep the default values of 26 degrees. However, if we change this to 30 degrees, making it equal to the latitude of the allocation, let's look at the difference. Very, very small difference in power. If we choose the angle, similar to the latitude, it will not give any it will give a very, very small decrease in power, very, very small value. If we click on open detail, You will get the details of the system. Here you can see the sun curve, similar to the sun curve that was obtained in the lesson of the distance between BV rows. Here, you can see the average hourly profile, which are representing how much what hour generated in each month and during the hours of the day. Here, for example, at 6:00 P.M. 6:00 A.M. If you go and increase until 12:00 P.M. Then goes down and so on. Here gives you for different months. This figure is similar to this one. January, 7-8, you will get this amount of energy 8-9, this energy in what hour and so on. This is a monthly average, how many what hour for each month. Now, this is a design based on the global solar atlas. However, there is something which is important here. When we are designing, let's say, for example, I'm talking a of grid system. I'm talking at of grid system. We said before in order to design an off grid system, the tilt angle should be equal to the latitude of the allocation plus 15 degrees. Now, why do we do this? Because this will be the best angle for harvesting or obtaining electrical or maximum power, maximum energy in winter. Remember that winter is the worst month in generation of electrical power. We design of the of grade system based on tilt angle plus 15 degrees. For the grade, it will be equal to the latitude. For the systems working in summer, it will be latitude -50. Here we are select, if we select, let's say, delta angle equal to the latitude like this and open detail. This is for 30 degrees. You'll find this is the power that we have. Now look carefully at the difference between the highest months and lowest one. If you look at August, which are representing summer in Egypt, compared to December, which are representing winter in Egypt, look at the difference in energy produced. Here in August, V out equals 146.2 kilowatt hour, 164.2. In December, which is the lowest month, 118, you can see approximately 50% difference between here and here. You can see approximately, let's just read this, 162 in summer, or in August and in winter, how much exactly, 180. 100 and e. You can see at f kilo difference between these two months. This difference is equivalent to 50% for summer, 50% additional to winter. You can see large gap between them. Now, if we do the method that I discussed in the course, which is designing latitude plus 15, in order to balance the energy produced throughout the whole months. Latitude equals 30 degrees. Add 15 to it, it will be 45. If we change this to 45, In order to design based on the worst months, you can see change in energy. Energy produced is lower. However, let's look at the palans in the generation. You can see almost all of the months are close to each other compared to the previous case. If you look at the highest months, August, 148.5, 148.5 for August or summer, for winter, look at here, 126.8 for winter, 126.8. You can see difference between them is just 20 kilowatt hour. Compared to the first case which had a large gap, 50 hour. That's why for the of grade system, you design based on the worst case in order to make the system provide enough energy in the worst months, which is winter. However, when I design on grade system, I design based on the latitude equal to the longitude in order to what in order to get the maximum energy from the system because it is a grade connected system. Okay? Now, let's say you have finished everything you would like to do with the global solar Atlas, you can download a report from it. Li just click on Report. Then chill the format, you would like BDF or Excel and click on download. Now the report is format, click on it, and you have a report coming from the BV syst. Now, another thing here, if you look at here, This page support slash methodology. This one gives you the assumptions or the theoretical model assumptions. You can see that here, for the small residential, it is assumed that the system is oriented portrait. The solar panels are installed portrait, portrait like this in the vertical and for the commercial and the other system landscape, which is horizontal panels in each row. For the self shading, Here, theoretically, we have a 2% self shading. For the residential, no shading effect, for medium as, there is a shedding effect, and so on, gives you losses in cables, how much percent losses, how much losses in transformer, and so on, and even the inverter efficiency. This is a theoretical model. Simulation based on this values, which can be a little bit different from the real case because it depends on the actual values of the efficiency of inverter and other equipment or other values of this equipment. In this lesson, we talked up the global solar outlos and we'll learned how to use it and how can we simulate the generation energy of BV system? 19. Hybrid Photovoltaic Thermal Panel (PVT): Hi, and welcome everyone. In this lesson, we will talk out another type of PV panels called the hybrid photovoltaic thermal panel or abbreviated as PVT. Now, this type of panels is used to do two functions. Number one, it is used to convert the sunlight into electrical power, and at the same time, it will provide us with heated water or hot water. How does this type of panels work? First, a standard foot voltaice panel converts 20% of the incoming solar light into electricity. The rest of the energy is dissipated or lost as heat energy. For example, if we have a PV panel with an efficiency of 20%. It will convert only 20% of the sunlight, and the rest of this will be converted into heat energy going to the BV sol. Remember when we talked at the relation between current and voltage with respect to temperature. We said that the temperature has a bad effect on the solar panels. As temperature increases, the power generated will start going down. As the efficiency of the panel will also go down. Now, something which is really important here. When I talk a temperature here, I'm talking about the temperature of the BV cell. When we talk about it STC condition at 25 Celsius degrees, we are talking a the temperature of the BV cell. When the temperature of the cell increases, let's say in a hot weather, it will let's say 45 Celsius degrees. When the temperature of the cell increases, the power generated will be reduced. Here, why does the temperature of the cell increases? Because the rest of the the rest of the sun irradiation is converted into heat energy transferred to the BV cell. Now, another thing is that in addition to being wasted or the heat energy is wasted, 80% not converted into electrical power. This heat energy is also detrimental to the solar panels foot voltaic efficiency, which means it drops when the panel rises in temperature. The same what I just said that when the temperature increases, this heat heat energy leads to increase in the temperature of the PVs. This will lead to decrease in the efficiency of the photovoltaic panel. In order to solve this, we have a new technology called the hybrid photovoltaic thermal panel or called BVT. A two in one solar technology. This type of panels is designed by a company called the dual sun. The dual sun or dual sun company has one type of PV panels called the spring hybrid panel. Now, what does this do? It does two functions. Number one, in the front side of the PV panel, we generate electrical power, and in the left side or the back side in the back side or the rear side, The extra energy, which is the heat energy in the BVS is transferred to a circulating water using a heat exchanger. This will lead to reduction in the temperature of the PV panel, and at the same time, it will provide us with hot water or heat energy for residential purposes. Let's understand this idea. Let's delete all of this first. We have our PV panel, which is a spring here. In the front side, we convert the electricity or the sunlight into electrical power. By using the monocrystalline side. On the pack side, we have large heat energy inside the cells. In the PAC side, we added heat exchanger. You can see lots of tubes here. These are tubes in which we input, we add some water cold water that will go the BV cells. It will go through the system. So the heat energy inside the BV cells or the BV panel will be transferred to the tubes here. In the end, we will be able to get hot water. As you can see here in this figure, you can see we add it from here, cold water that will go through the hot PV panel, and then it will provide us with hot water from the side. This heated water or hot water will go through the building. Or the residential building to provide hot water for the building. We did here two functions. Number one, converted sunlight into electrical energy. Number two, Using the heat exchanger on the back side, we provided hot water to residential building. We don't need any type of heaters inside the building itself. Another thing is that when the heat energy is transferred to the cold water, the temperature of the PV panel will start going down, which means the efficiency of the panel will increase, and more electrical power is generated. The water flow has two pets, number one, double heat as the water can reach a temperature of up to 70 celsius degree, and it will cover the building's various heating needs. Number two, double post, the water also calls the foot voltaic solves and improves the electricity output pie 5-15% depending on the usage. Now, how does this PV panel looks like? It looks like the spring, this is the front side, and this is the pack side. In the pack side, you input water from one tube like this and it will go through the PV panel. You can see this part is the junction box, and in the end, you will get hot water from the other side. The dull aun spring is an example of a hyper solar panel that produces post electricity and hot water, making it more efficient than standard V panel. They are used to maximize energy generated by the sun. By using BBs and solar thermal collectors. Solar thermal collectors, we do the do this. They are used to provide hot water. For example, we have tubes. In reality, the solar thermal collectors only. We have large tube that contains water, cold water, and due to the irradiation coming from the sun, this water will start getting heated. After this water gets heated, it will go to the building. Now, another thing is that we sometimes use heat exchanger. For example, the sun itself, heats a tube filled with oil, and then the oil will be exchanged with with the water. Depending on the system itself. The BV salts convert the sunlight into electricity, while while solar thermal collectors, absorb the heat from the sun and use it to heat water or air. To be more specific, it absorbs heat from what from the PV panels, the high temperature from the BV panels. This is the figure that we talked about. In this sloson, we talked with another type of PV panels called the hybrid photovoltic thermal panel. 20. Off Grid, On Grid, and Hybrid PV Systems: Hi and welcome everyone to this lesson in our course for solar energy. In this lesson, we will talk about different types of BBS systems that we use. So we have three different types of PV systems. Forest that we have the off-grid PV system. We have the on-grid PV system and we have the hybrid PV system. Let's start by understanding the different difference between these three systems and what are the components inside these systems. So first we have the off grid system, or the off-grid PV system, or the stand alone PV system. So an off-grid system or a stand-alone PV system refers to as PV system that is not connected to the electricity grid. If you look at this figure, we have this bv system, all of this representing our PV systems that provide this power to our house. As you can see, is that the main source of electricity is our BV system. We don't have any connection to the electrical power grid. So we are in the off-grid system or a stand alone system. So it means that all of the energy produced is a stored and used owns assigned to always ensure access to the electricity off grid solar systems require battery storage and backup generator if you live off the grid. So let's start by understanding how does the system work. So Forest, we have the solar panels that we discussed before. Solar panels that will convert solar energy into electrical energy. So this solar panels will provide DC voltage. Remember, DC voltage. Then that our DC voltage, let's say we have two terminals, is our positive terminal and the negative terminal of the solar panel. These two terminals will go to a charge controller. So what does the charge controller do? It regulates the charging of a battery. Okay. The output of the charge controller will go to the battery. So the charge controller regulates the charging of the battery Pi, controlling the voltage. Okay? Then the battery here is also DC voltage. Dc voltage. So we have an inverter that will take this DC voltage coming from the solar panels or from the batteries and provides it or change it from DC to AC, suitable for our home. We take the DC power coming from the BV system or from the batteries and convert it to ACA required for our house. Let's understand more about the system. So you can see we have solar panels. Solar panels will provide energy to our house, let's say 8 h a day, 8 h a day when the sun is available. Okay, So during this 8 h, I will take energy from the solar panels and will operate every equipment inside our house. Now, when the Sun is not available, there is no source of electricity. That's why we use batteries to start to providing electrical power at night. Okay. So you can see that our house has two sources. Forest from the solar panels. During the day. Solar panels provide DC voltage that will go to the inverter to provide electrical power to the house at night when there is no sun and no power coming from the solar panels. The battery as well as started discharging and providing power to the inverter, which will provide power to the house. So the solar panel Z during the day and during the night, we use the energy stored inside the pattern than solar panels during the day. It provides power to charge the batteries. Charge these batteries, and at the same time gives the power to the house. At night, we dislike charges, the batteries to provide power to the house. Okay. Now, usually we have batteries, other systems or other how is use a backup generator, e.g. a. Diesel generator, as a backup power instead of the patterns. On top of this, battery bank typically needs to be replaced after ten years and also finds that batteries are complicated, expensive, and decrease the overall system efficiency. So we have to understand that that main function of the batteries is to store energy from the solar panels during the day and provides power during the night. So you have to understand that batteries are the most expensive component in the PV system, not the solar panels or the inverter or the controller. The batteries are the most expensive part or component of the solar energy system. So they are expensive and needs to be replaced after ten years. However, we need them in the off-grid system when we don't have any connection to the grid, we need batteries to provide power at Mt. You will find that off-grid solar systems can be cheaper than extending power lines and certain remote areas. So let's say you are living in allocation, e.g. on the mountains and you would like to have electrical power. So extending power lines are providing transmission lines or building transmission lines to transmit electrical power from anywhere to that mountain. It means that we will need more money. It is much more expensive than installing the BV system. Okay, So instead of extending transmission lines with electrical power, we built an off-grid system, all solar panels that will provide electrical power. Of course, living off the grid means you are self-sufficient, which will help us to feel good. Now, why is this? Because of course, any power failures on the utility grid, it will not affect you. So if the power grid has any problems at all, you will not be affected by it because you are an off-grid system or not connected to the grid, you are completely dependent on the solar panels. Okay? Now, there is another system which is the on-grid PV system. So the on-grid PV system, we are now connected to the power grid. You can see that this system, which is called desert on-grid system or a grid tied system. The utility interactive system that grid back feeding. All of these are terms that will describe the on-grid system, which means solar energy system connected to the utility power grid. Okay. So how does the system work assembly, we have solar panels, again that will provide DC power. However, in this case we have directly an inverter. The inverter. What does the inverter do? It takes us a DC power and converts it into AAC CO2 poll for that grit. And at the same time suitable for our, our home. Okay. So you can see that in this system, we don't have any charge controllers. We don't have any batteries. So the cost of this system is much lower than the off-grid system. So we only have solar panels and we have inverters. Okay? So solid balance and inverters. Now we will find that here in the system, we provide power to the home or our home, and we provide electrical power to the utility grid. Okay. So we provide power to these two components. And at the same time, at the same time, this is happening during the day. So during during that day. Okay, during day, we will provide electrical power from solar panels to home and the grid. Okay. So we have electrical power going into the house and going to the utility grid. Now at night. What will happen at night? At night, we don't have any power coming from the solar panels. So in this case, we are going to take electrical power from the grid to our house. So from grid to house. So during the day from the BV system to our house and the grid, at night, we will take power from the grid to our house. So you can see that in this case we have two powers. So you can see that we are sometimes providing power from the solar energy system to the grid. And other times we are taking power from the utility grid going to our house. So you can see we are sometimes providing power and sometimes you are taking power. That's why we will have a net meter which is installed here, which will help us to reduce their electricity bill. So you can see that when we are providing power to the grid, we take money. We are taking money from the government. When we are taking from the grid to our house, we are paying money. Okay? So sometimes we are taking money and sometimes we are giving money. Okay? So this depends on what the red zones or power flow. Okay? That's why you will need a net meter to measure the power provided to the grid ends up are taken from the grid. So we can in Z and reduce our electricity. So we will save more money with net metering, which will provide better efficiency rates. Net metering plus lower equipment and installation costs. So first, why do we have better efficiency? Okay, So if you look at here at this first system, let's delete all of this. For us too. We have a power coming from the solar panels, Let's say B1. Then this power will pass through the charge controller. So they will suffer some losses. So we have, depending on the efficiency of the controller. So we have some losses here. Then the battery also have an efficiency. Inverter also has an efficiency. So you can see our power will be suffered from three efficiencies depending on the controller, battery and invert. However, in this system, you can see that we have only the efficiency of what? Of the inverse. So we have better efficiency or lower power losses. And the same time we have lower equipment and installation costs because we have here inverter only, but in the off-grid system we have inverter battery and the charge controllers. Okay. So you can see that batteries and the other stand-alone equipment are required for a fully functional off-grid solar system, which will increase the total cost and the maintenance of the system. And remember that we need to change the battery the whole time. So you will see that the grid tied solar system or the on-grid solar systems are generally cheaper and simpler to install. The width net metering, you will find that homeowners can put this excess electricity onto that utility grid instead of storing it themselves with the battery. So e.g. if we are providing, let's say ten kilowatt. Okay? And at anytime we need e.g. let's say e.g. this providing ten kilowatt hour. As an example, energy. And our house require five kilowatt hour, okay, as an inertia. So the excess energy will go or the excess five kilowatt hour, we'll go to the grid. So any excess electricity will go to the utility. And instead of storing it inside batteries, you will find that many utility companies are committed to buying electricity from homeowners at the same rate as the soil surface. So e.g. if I consume electrical power from their utility, let's say each one kilowatt-hour cost is e.g. $1, $1 for each. Let's type it in another way like this. So each kilowatt-hour cost, e.g. $0.1 per kilowatt hour. So each kilowatt hour consumed from the utility grid, we pay $0.1. At the same time, if you provide. Electrical power to the grid. Some companies will give you all so 0.1 polar bear kilowatt hour. So when you consume, you will pay 0.1. When you provide electrical power, you get $0.1 per kilowatt. Okay? So we'll find that the utility grid is acting as a virtual battery. So instead of storing the excess energy inside batteries, as we did in the off-grid system. We are restoring them as if it is a virtual battery. As if it's a grid is virtual pattern in which we will take the electrical power at any other time. Now, let's see the comparison between on-grid and off-grid systems. So again, on-grid system or the off-grid system. First, we have solar panels connected to the inverter, which will provide electrical power to the house. And on sometimes we have an optional which is a generator or a diesel generator. Now we have to understand that there are some inverters, some inverters that will act as our charge controller. And at the same time in volts. So it has terminals or pens for a charging the batteries as if it is a charge controller. And at the same time it has other terminals which will provide the AC power. Okay? So some inverters do the two functions together. Georgia controllers and an inverter as, as at the same time. But usually, usually we have two different components or two separate components, the charge controllers and inverters alone. So in this figure, this inverters do the two functions together. Okay? The on-grid system, we have solar panels and inverters and the utility grid as n into utility meter connected to the grid. Okay, so we don't have any batteries in the on-grid system. Finally, we have a hybrid between sustain, what does a hybrid PV system means? It means that we took the best of the grid tied system or the on-grid system and the best of the off-grid system. So you can see we have solar panels, charge controllers, then batteries, then inverter, and providing power to our house. So this part alone representing, representing the off-grid system. Okay? Now, this part alone is a utility inverter and solar panels. This part representing the on-grid system. So as if you combine the parcels that grid ends of grid systems together. Okay? Now, why a system like this is a good system or will provide more efficiencies and others. You will find that this systems can be described as an off-grid system with a utility backup power. So we have here an off-grid system which is as part. Okay. And for any problem inside the PV system, we have a backup system, which is a utility grid. Okay. So we can say it as an off-grid system with a pack of power coming from the grid. Or it is a great Bright solar energy system like this. Sunspot. Solar panels inverter ends a utility. This is an, a grid connected or on-grid system with an extra battery storage, which is from the off-grid system. Okay. So the hybrid system, you will find that it is less expensive than off-grid solar systems. Now why is this? Because you don't need any backup generator. So in this system you don't need any back abs are tight or such as a diesel generator. If any problem happened in the B versus time, you can just take the power from the grid. And at the same time you can use a smaller batteries. So you can see that in this figure, this solar panels, it during the day will provide power p, let's say P1. This P1 will be divided as some of them will go to the batteries, will go to the house, and the other will go to the utility grid. So you can see it's divided into three parts. That's why you don't need a big batteries to absorb all of the power from the solar panels. You can simply provide the excess energy to the utility grid. So you can Darwin size, the battery is required. Now, off peak electricity from the utility company is cheaper than diesel. So what does this mean? You will find that during the day. Okay. Let's say this is the price of electricity per kilowatt hour. And this is a time of the day. You can see that during the day, the price of electricity, it changing all of the time. Okay, depending from 1 h to another. So what we can do is that do during the peak hour, when the electricity is very expensive, we will absorb our electrical power from the solar panels or from the batteries. To reduce our electricity power. During the off power we can absorb as a power from the utility grid. So you can see that the homeowners take advantage of changes in the utility electricity rates throughout the day. So you can see that the price of electricity is a changing throws a day. That's why you will find that solar panels have into outputs are most electrical power at noon, not long before the price of the electricity peaks. Will find that your home and electric vehicle can be programmed to consume power during off-peak hours or from your solar panels. And you'll find that you can temporarily store whatever excess electricity, your solar panels and batteries, and the body tones or utility grid when you are beds are most for every kilowatt-hour. Okay. So what does this even mean? So let's say the price of electricity is expensive. So you will take as electrical power from the batteries or from the solar panels. And at the same time, when the utility grid, if you provide electrical power to the utility grid at a certain time, that money you will make is much higher than any other time. During this time, you can start providing electrical power to the grid to earn more money. Okay? So you will find that your house is programmed to consume power during the off peak hours. Let's say if you have a control on this, so you can win, the electricity is cheap. You can simply take it from the solar panels or from the grid. However, when the electricity is expensive, you can start providing electrical power to the grid. So you can earn more money. That's why this system is called a smarter solar system. You will see that this concept will increase, its important will increase as times we, As we go to the Smart Grid concept in the coming years. So in this lesson, we talked about with the hybrid PV system, on-grid system and as the off-grid system. So we talked about all those other types of PV system. Now in this course or in the rest of the course, we will start talking about the rest of the components, such as a charge controller, the inverter, the battery banks, or the battery itself, and so on. Then we will go towards the design of the BV. 21. Introduction to Batteries: Hi, and welcome everyone to our course for solar energy. In this section, we will start talking about the batteries inside the BV systems. Let's remember what is the batteries are, what are the main functions of the batteries in size a BV system. So the battery is accumulate the excess energy created by your PV system and then store it to be used at night or when there is no other energy input. So if you look at this system, which is an off-grid system, you can see what should we have our load, which is our house, and do we have our equipment, which are the solar panels, which will change that sunlight or the irradiation or solar energy into electrical energy. And it provides DC voltage. And do we have here our inverter that is responsible for converting the DC voltage coming from our batteries into AC voltage for our house. Now, as you can see, we have between the solar panels and the battery system, we have controller, which is a charge controller. The function of the charge controller is regulating that charging of the batteries. Now we will learn in this section that lead acid batteries, or the lithium ion batteries, has a charging cycle, charging charging cycle. And its format of three stages. Now in size, these three stages, which depends on the state of the battery, has a state of charge, which we will understand what does this mean? And this section. Depending on the state of the charge, we have a three stages. Three stages, we have different values. We have a charging current, we have a float voltage, we have absorption voltage. All of these we will find in signs that data sheet of the battery, which will help us to add this to the settings of that charge controller. We will learn how can we get a Z is values in the datasheet lesson of this course or batteries part. So that Charles you control, regulates and has these cycles That's reaches the three stages of a charging our country. And also think about the charge of control is that it reverses the overcharging of the battery. So if our batteries reaches 100% or fully charged it, then the charge controller, we'll just apply a very small voltage or a certain voltage. Gold is afloat voltage, which will keep it at 100% and prevent as the overcharging of the battery. Now, all of this we will learn in this section. So the function of the battery is that they take the energy from solar panels, excess energy. Remember that during the day, solar panels provide electrical power to our house. Answer our excess energy which are stored in the batteries. This excess energy will be used at night or if the panels are not available or the Sun is not available for any other reason. So during the charges, the batteries takes electrical power from the BV patterns and convert it into me onto chemical power or chemical energy to be more specific. And during this a charging, it will take the chemical energy and convert it back to electrical energy to start using it. Now, why selection of batteries is important in BYU systems? The sizing of batteries are, is very important because they can represent up to 40% of the total cost of the BV system. That's why you have to select as a batteries that will give you the best number of cycles or the largest number of cycles and always a good efficiency. Now we will understand this when we talk about the different definitions involving the batteries. And we will also talk about different types of batteries. So you have to understand that there are some batteries that can not be replaced as through as a whole lifetime. So e.g. if the solar panels will remain for 20 years, some types of batteries, such as lithium ion, we don't need to change it at all or don't require any replacement. Unlike other types such as the lead acid batteries, they can be replaced several times during their own lifetime. So why is the cost of these batteries representing larger portion of the whole BV system. Now let's talk about the battery's voltage. What is the voltage of the battery is that we use. Solar batteries are available in a few common voltages size this is a common voltages, or these are the common voltages. There are six volt battery. At 12 volt battery, had 24 volt battery and 48 volt battery. There are, of course, the newer technology, which you will find a battery voltage of 2 v e.g. or 1.2 volt and other values. But these are the values which are common in the market. Now as an example, you can see this solar energy battery. You can see, as you can see, six volt battery through 100 ampere, hour slashed and hours. We will learn what does this mean and what does this mean in the next lesson, in the C rate and in the battery capacity lesson. Now, another one of that solar batteries. Here we can see a 12-volt solar battery. This one, e.g. as we just said, you can see this one is at two volt and the Gibbs 1,000 ampere hour, very large amount of energy, and it is two volt battery. Now here is another one. This one is that Joel battery. You can see here the total battery, which is one of the types of the BV system. You can see it'll involve a regulated gel battery, one of the types of the lead acid batteries. This one is a 24 volt. Here you will find that we have a lithium iron phosphate. 48 volt. Okay, 48 volt. This one is under the family of lithium batteries. We will talk about lead acid batteries, including the flooded lead acid batteries, is absorbed big gloss, matte than Joel batteries, lead carbon. We will talk about lithium batteries and more in this spot. So in this lesson, we had an introduction about the batteries in the PV system and over all, small introduction. 22. Practical Recommendation of Battery System Voltage: Hi and welcome everyone. In this lesson. This lesson we will talk more about that battery system voltage. So what I mean by this, we will take the batteries and combines them in series to increase the total voltage. So what are the systems that we use? What is that voltage that we use in BB system? So that practical recommendation of a battery system voltage. And here I'm not talking about one battery. I'm talking about with that combination or the total battery voltage together. So here you will find that the most common volts used for BV system is at 12 volt, 24 volt, and 48. These are the three common voltages that you'll find in the off-grid systems. Now what I mean by this. So we have a group of batteries, these patterns when they are combined together, they e.g. give us our final post if terminal, and define a negative terminal plus minus these two terminals, or someone which will go to the charge controller. And at the same time z will go to the inverter. The voltage across them can be, as a final voltage, can be 12 or 24 or 48. Now exact question is, on what basis that I can select on what base do I select at one millivolt or 24 or 48. Now remember there is no standard such as I triple E or IEC telling us which a voltage would I use? It is all practical knowledge. Practical recommendation for this ranges is that if you have a small installation, small installation, older is alludes of the house is up to 1201. Then the system voltage here used is that well volt. So if you have a six of Walter batteries, you'll combine two batteries in series to form our final voltage of 12 v. If you have a medium installation which is between 1,000 and hundred 200 to 2000 watt. Then it's called the medium installations. And in this case, we will use that 24 volt DC system. If you have higher than this, greater than 2000, then you will use a 48 volt or higher, such as mine, six volt DC, the common hour 1,224.48. Now, why? Because these values are safe to humans. More than line six volt. However, you will find in the market that there are inverters, charge controllers that support mine six volt. So I have to mention this. Now, as you can see here, let's say e.g. we have at 24 volt system, then I will take it a volt battery and honors of 12 volt battery and connect them in series. You can see all stiff terminal negative or positive negative in order to connect two batteries in series. As we will learn in the next lessons, series connection. The negative terminal is connected with the positive term. Then the final negative and positive will give, will be as an input to the charge controller and invoked. So since they are connected in series, so 12 0 plus 12 24. If we have three in theaters, it will give us six. If we have four in series to give us 48. Now I have to mention something which is really important is that we can use to batteries to form a 24 or we can use a one big battery, which is a 24 volt one battery. Here's the same idea we can't necessarily using for 12 volt battery. We can use one big batteries. This is a design process. You select what you see. Co2 and water is available inside the market itself. Now I would like to mention something which is really important is that if we select that too when T four volt system as an example, then we have to select that charge controller or an inverter that support is at 24 volt battery. And we have to select our charge controller that give 24 volt or supports at 24 volt battery. And also we have to connect these panels in series to give enough voltage to charge a 24 v so that the system itself, all the components or system are in resonance or in synchronization with each other. So all of the elements that we select are aligned with each other as they are compatible with each other. So as an example, there be V panel corresponding voltage for each type of batteries. So the selection of the panel depends on two parameters that require the energy system. And the connection between as a connection also depends on the battery voltage. Now what I mean by this, so we have here our house, which requires certain amount of power kilowatt hour in one day. Now, this kilowatt hour is the final energies that goes to the house. And through our system, we have some losses. At losses, the two cables, you losses inside inverter, losses inside the charge controller. So we have the kilowatt hour required or the energy required to buy the house plus losses. Now, we have to make sure that our BV panel can give us this amount of energy, the amount of energy required by our house, which is of course to divide it to energy during the day and energy for the battery to and give energy to the house at night. We need to pass here at kilowatt hour for the house and during the day and energy stored inside the battery in addition to losses occurring in the system. So that is how we select as a balance, as we will see when we design the off-grid systems. Now, another thing is that the battery voltage. Now, if it is a 12-volt, it will be different from 24, different from 48. Now with these different voltage will lead to different seamless connection of balance. The balance should have enough power to charge the batteries. Okay? So as an example, if you look at them in the market, you will find e.g. we have a 12 volt panel. Let's say we have a 12-volt battery voltage and we have a 12 volt panel. So what does this 12-volt mean? That, well, volt is called the nominal voltage of the panel. That 12 volt is not a measurable value. We cannot measure it. It is not the open circuit voltage. It is not the maximum power point tracking voltage. So what does a 12 volt mean? It means that this panel is designed to charge at 1 v battery. So if you look in the market and you see at 1 v solar panel or a 24 solar panel. This means that this panel is designed to give, this dying, designed to give at least enough. You can see here it is designed to our atleast enough voltage to charge as a 12-volt battery under worst-case conditions, which includes low irradiation, high temperature. So at 12 0 volt battery, e.g. needs at least 13.6 of all two chars. That's why adds the indoors a worst condition. The panel will give this value, which is 13.6 volt. Now, you have to understand that these values are 0.6, where the word do we obtain? We obtain it from the data sheet of the battery itself, as we will learn in this section. Now, this means that in the perfect conditions at well of all the solar panels may give an outward around 17 volt or more. So that will revolt. This one. That maximum power point tracking here. This panel under the normal condition is the maximum voltage is equal to 17 volt or more. So this 17 volt is enough to charge the batteries. And you'll understand how can we connect or not, how we connect. How many panels are required in series to charge the system. The system is synchronized with each other, as you will learn in the next lesson. For a 24 volt battery, the panel voltage is around three to six volt. This is a voltage that the panel gift to charge the battery under the worst conditions. Now, as you can see here, we have our charge controller. Now is the charge controller is between the panels and the batteries. Now, here, it is designed for 12 volt or a 24 volt batteries. So the charge controller here is designed to charge at 24 or 12, and it already automatically it will identify is the battery itself, is it 12 volt or 24 volt? Now, this charge controller will accept up to maximum BV input voltage, voltage DC. So it can take up to 50 v DC from the solar panel. So he was, the panels are connected in series and they give 50 v DC. It will be able to charge these batteries. This is a maximum value. Now another thing you can see, rated the charge becomes the maximum charging current of the solar charge. Control the maximum current can it give to the batteries to charge it? Now, how can we identify this value? How can we know the maximum a charging current of a battery? This will be also given from that data sheet, as we will learn in the next lessons. Now another thing here, you can see battery type, ECM gel and the flooded. So this one, this is a charge controller, can be used for EGN, battery absorbing glass, matt, absorbent, gloss, matte, gel, and flooded. These three types, or lead acid batteries. So this charge controller is designed for them. So I hope you, I hope this lesson, how would you understand more about what that BV panels, corresponding voltages and different practical recommendation for the battery system. Voltage. 23. Components of 24V and 48V PV Systems: Hi and welcome everyone. In this lesson, we'll give an example on a 24 volt BV system and 48 volt PV system. So you can understand how does the components or how does the components inside they'd be V0 system are aligned with each other or are synchronized with each ours. So you will see here e.g. this is from clean energy reviews, this picture here or this image illustration from clean energy reviews website. So you can see here, look carefully at this system. We have here, our inverter is at 24 volt inverse. So design for batteries operating at 24 volt. Okay? Now if you look at the batteries here, you can see 12 volt and also to all volt z are connected in series, so they form 24 v DC. And then we have the final positive terminal. And following a negative term. These two terminals are connected to our invert, which will be connected to our AC loops. So we can see 24.24 volt in volt. Now we have the charge controller here. Now if you look at the charge controller, you will see several inputs. The first two here with the finger or the sample of the solar panel is used to take, suppose there was a solar panel and negative or solar panel. You can see it's a final poster which is a red one, and the black one which is negative. And you can see here is a whole step of the batteries and negative of the batteries. You can see it on the sample of the battery. Don't worry, we will see a closer look at this. As an example of a charge controller. Then if you have DC loads, you will connect them to input here, you can see an input here for the DC load. Now remember, don't ever, don't ever connect a DC load directly to the batteries. Why? Because it will damage the batteries. However, that charge controller can disconnect as this looked for that lifetime of batteries and to protect it against damaged, don't ever connect directly to it. Now if you look at the solar panels here, you can see this one and this one. So we are operating at 24 volt system, 24 volt DC. This panel will be a 12-volt. This panel will be also 12 volt. So z, when z are connected in series, they will form a 24 volt. Now, you can see both positive, negative, positive, negative. Now, these panels are connected in series. You can see it's all stiff terminal, connected to the negative terminal. Then it's a poster which is the final one. And then negative which is a final negative. You can see that panels are connected together using what? Using an MC4 connection that we talked about before. And at the same time you will see that the charge controller is connected to the final poster and final negative using MC4 connections to MC4 connectors. You can see two connected between them and the charge controller. So what you can see, everything here is 24, 24 volt inverter, 24 volt battery at 24 volt solar panels designed for that 24 volt system Battery. Now, let's look at a more complex system. Now we have here in this system that same ideas, this one, or this system is an on-grid system or a hybrid system. Now what I mean by this, you will see that here we use something which is called solar hybrid in water. Now what does this inverter do? This invoked is really amazing. Why? Because it has several functions. Number one, it has a maximum power point tracking charged controller inside it. So it has a maximum power point tracking charge controller inside it. It has inside it invert, which you will take the DC from batteries and convert it into AC for our loads. This inverter also acts, accept this power from the AC grid. So it can take electrical power from the AC grid and the charge batteries. It also accept this input from generate or such as a diesel generator. So you can see the hybrid inverter is complex. It contains lots of things, are lots of devices in one place. That's why it's called the hybrid inverter. Now, you can see that here. This inverter, instead of the maximum power point tracking charge controller, it will take the input from the PV panel. You can see this PV panel system has a final poster and define a negative. So Z will be connected here to this inverter. Now what does this will do? It will change as our voltage across that PV panels to produce maximum power. So it is acting as the maximum power point tracking charge controller. At the same time, the charge controller inside it will charge the system batteries. Z is buttress. And the same time it will take energy at night from Z is batteries to convert it into AAC for our AAC loops. And also it has a location of the input for the AC grid origin rate. So you can see how many function does this solar inverter do? It, it does is a function of a maximum power point tracking charge controller and inverter at the same time. Now, you can see that this system is a 48 volt system. You can see this batteries. If I remember correctly, this one. If I remember correctly, they are lithium ion phosphate batteries, one of the types of lithium batteries. Now how did I know this is our 40th voting can see 48 volt. 48 volt. And look carefully, the ball stiff connected with what? All stiff connected with boast. Bolstered, connected with post them here, negative connected with, negative, connected with negative. So z3 batteries are parallel to each other. So since they are parallel, the same voltage, however, is that amperage or the emperor our will increase. Now, you can see that here. So this system is a faulty add volt system. So the negative will be connected to negative and all stuff connected to post. Now let's understand more about this inverter. You can see this is the hybrid inverter. This is the specs of this inverter here. As you can see here. You can see this in voter suspects one piece, five cells and what 48 volt hybrid environment. Now, you can see that this is a spec. So let's look at it. First. Rated AC in what voltage? Ac input. Ac input. What does this mean? It means the input to the invert this AC input, which is 110 slash 120 volt AC. This voltage representing the voltage coming from the power grid or coming from machinery. At an emergency generator or a diesel generator. Look at the rated output power. So it is our five sells them to what inverter. The maximum output power is 5,001. This is the maximum power that will go from this and go to AAC. Now another thing you can see, output voltage waveform is a pure sine wave. So it produced a pure sine wave, not a modified sine wave, which is of course in great for us. You can see also the efficiency, efficiency as great as landline to five per cent. So it's software is only from five. Software is only a 5% losses. Now, you can see here maximum BV input power. This is really important. So it means that the power coming from the PV panel, maximum input should not exceed 5,000 to one. Okay? So the panels here together does not exceed 57, and this is a maximum input power it can take from the PV panels. Now is the battery voltage range here, what I mean by battery voltage range, representing the battery is connected to 40-60 v, as you can see the system as a 48 v. So it is in this range. Look at Amazon seeing here, which is the battery type, lead acid or lithium battery. So it walks with lithium batteries and lead acid batteries. Okay? Another thing here you can see maximum charge accounts with a maximum current, it can give its 40 and bear. Now look at this, which is really, really important part. You can see BV, operating voltage range, maximum power point tracking voltage range at these two is really important, especially as a maximum power point tracking. Now what does this mean? It means that if the voltage is coming from this system, total votes coming from this system is in this range 120-500. It can take it can be connected to the inverter and it will operate if it is higher than 500 or lower than hundred 20, it will not operate. Now with a maximum power point tracking voltage range, it means that if the voltage is between 120. And 400 volt, 50 v, it can extract the maximum power from the panels. Okay, this is what suspects mean here. Now, if look at this picture, here, you can see something which is really important. Here you can see 120.450 v DC. So when I'm connecting my own panels, I make sure that this connection will produce a voltage in this range or does not exist this range. So as you can see here, if you look at the panelists that is used in the system, you can see here 18 panels. We have 123-45-6789, Berlin to Amazon mine. So this mine are connected in series. And this is a string connected in series. And these two strings are parallel to each other. Now, you can see that the rated power is 195. What? This is the rated power of these panels. So how many panels? 18 panels, multiplied by one minus five. So it will give us approximately 3,600 less than this value. So the power coming, maximum power coming from the BV panels using the system is 3,600 watt. You can see that the maximum input here, maximum NPV input power is 5,012. So that's 3,600. What is lower than this value, which is acceptable for the inverse. Now, another thing you can look at here is that the maximum or peak VMB, maximum voltage, or the voltage at maximum power, which is 19 v. Now how many panels connected in series? We said mine panels connected in series multiplied by 19 will give us, as you can see here, will give us 17 1 v. So you can see 17 1 v is in the range of the maximum power point tracking. So this system, so this hybrid inverter can extract maximum power from this pattern. Why? Because 171, which is the formation here, nine panels in series, gives us 171, which is in the maximum power point tracking range. Now, another thing here, which is that charge account here, maximum charge account coming out to the batteries. Now, let's say that the current here, that the input or the maximum input current for champions, maximum current coming from the bank. So we will look at the short circuit current which is 12 and bear. What we do is that we look at the maximum comes to the maximum current is 12.23 and pair for each string because the current will not change in the string. So the more balanced connected in series, a voltage increase, but the current is constant. So we have one bottle to another one. So we have two strings parallel to it, which is approximately 24 and bears. Now of course we didn't add any safety factor. But anyway, you can see that 24 is less than 40 and B, which is acceptable for us and better for the inverter itself. So we have many factors that we consider when we design a PV system. So I hope this lesson was helpful for you in understanding more about Divi system. Don't worry, we will have off-grid system design and on-grid system design with manual calculations exactly. 24. Battery Capacity and C-Rate: Hi and welcome everyone. In this lesson, we will talk about a very important definition or specks inside the pattern, which is battery capacity. So what is battery capacity? Battery capacity is representing how much energy does our bathroom stall or how much energy stored inside our battery. Now, this battery capacitor energy stored representing, or the battery capacity represents the maximum amount of energy that can be extracted from the battery under certain specified conditions. And what I mean by salting conditions, the certain conditions or the discharge rate, that amount of current is taken from this battery is at temperature and many other effectors. We will also learn about this in the next lessons. Now, how can we measure the battery capacity? You will find that that battery capacity itself is measured in Our or in kilowatt hours or in Amperes hours. So as you can see, what our kilowatt hour and impair, both of them representing the battery. Now is the most common measurement, or as a battery capacities that we usually use is the ampere hours. This is really, really important when comparing between batteries. Now what does impair our mean? As you see here, we have, let's look at here, at this unit here and pair hour. So I'm pair hour, it means current. Hour means time. Kilowatt hour. It means kilowatts or what? Rub Rosen thing. The power multiplied by hours or hours, which is time. So what I say is that my own battery is 1 kwh. It means that it is equal to the power multiplied by time. So it means that if I take a power of 1 kw, in how much time in 1 h, or you can take e.g. let's say two kilowatt multiplied by 0.5 h. So they're multiplication will give us 1 kw. So what does this mean? If our battery is a 1 kw hour? It means I can provide one kill, a power of 1 kw to allude for 1 h. Or I can give two kilowatt load for zoster, 0.5 h and so on. The same idea for an hour. It means how many amperes I can give For how many times? For how many hours? As you can see, it is a product of the DC charge current, current taken from this battery multiplied bys that hours of DC charge. So let's say e.g. if I have 100 and bear our battery, it means that e.g. if my own load is one emperor, one amperes. So I can provide electrical power of one to allude of one ampere. For e.g. 100 h, their product that gives us 100 and bear out. Or you can say e.g. 50 and build Loot for just 2 h. In the end there multiplication theoretically will be equal to 100 and bear. Okay, So this is a definition of m per hour. How many emperors that I can take in how much hours or how many hours. Now, the most important thing is that you have to understand is this is not always the case. Now, what do I mean by this? Their product, their product is not equal to 100 and bears all the time the amount of m pairs or amount of hours that we use. Can it change this value? So you will find them e.g. inside the specs of the battery that you will find that the ampere hour, can it change if you are discharging at 100 h or discharging at 20 h. So charging actin hours. So depending on the discharge time or DC charge current, you will get different and better, as we will see right in this video. So this is one of the factors that can affect and per hour. So you have to make sure that the load you are connecting is not causing lower ampere hour of the battery. Okay, so let's just delete all of this and understand more. So let's say we have, again, this is another example here. We have 150 ampere hour battery, which you can see here. We can see this tie, this pottery. As you can see, a well regulated lead acid battery. So this is one of the batteries which is under the family of the lead asset, but this one is called Evolving regulated or completely sealed battery. So what you can see here, it is at 1 v battery and has an, a voltage or a voltage and add battery capacity of 150 AM pair. As you can see, 50 AM pair hours. No, Just an pair and bear hours. Now, theoretically here you can see that the battery is 12 v and 150 ampere out. So if I would like to see this pottery in what hours or in kilowatt hour. You know that that's a power is equal to voltage multiplied by current. Right? So here we have our carrots. And I would like to convert this into power or what? So I will multiply and bear hours. Boys a voltage to get how many hours? Okay? Or you can say, is that energy, which is what our, this is representing. Energy will be equal to power multiplied by time, or will be equal to v multiplied by t, voltage multiplied by current, multiplied by the time. Here. Current. And bear Time, which is our, so this is an bear out. So if I multiply ampere hour by voltage, I will get the energy, or how many watts hour or kilowatt hour. So as you can see, we took the 150 ampere hour and multiply it by the voltage of the battery, which is at 12 0 volt. So this will give us finally a house, 1,800 h or 1.8 kilowatt hour. Now, let's see more about this battery. So you can see that this battery is 150 ampere hour. So theoretically, if you are e.g. supplying current to a 7.5 and bear loot, you will be able to give it power for two when t hours. So 7.5 and payload for 20 h. Why? Because their product will give us 150 ampere hour. Or e.g. if you are going to supply and Lou allude of 15 amperes, you'll only be able to give it 10 h of energy. So you are going to discharge, this battery will discharge. And 10 h if it is supplying 15 amperes to allude. If it is supplying 7.5 amperes, it will last for 20 h. Again, if it is supplying to allude of surgery and pears higher amperes, it will be discharged and very fast in 5 h. So theoretically, here what we see here, this is a theoretical their, their product give us 1500, that gives us 150 ampere hour, and so on. However you will find, as we will see, is that this is not always the case. Depending on the discharge current. You will have a different amperage, as we will see in this lesson. Now, since we talked that powered battery capacity, or the capacity of a battery in ampere hours. We have to talk about the C rate or the discharge rate of a battery. So what does this C rate or C rating represent? This representing zest, safest, maximum continuous discharge rates at our battery can support. This rating is obtained by connecting a load to add battery. After connecting it to a battery, it will be that in a five or ten or 20 hour period. Now, let's understand this. So if you look at any country, any battery inside that data sheet or the specs of that battery or owns the battery itself, uses this e.g. this is a solar battery which has a capacity of 150 and bear our k, which we exhaust the xy plane. However, you will find there is an additional part here. It's called c. Then you can see this is 150 and bear our battery at Seton. Seton. So what does this represent? See then you can see the number beside it on the right side representing the hours of DC charge, 10 h. So if you are, if you are discharging this battery in 10 h, you will get 150 and burrow. Or you can simply say 10 h. It means that we can, looking at this one, it can means we have 15 and bear loop. So I can supply electrical power to 15 ampere elude for 10 h. That is what does a seat and mean. You can see this product will give us the rating of the battery or the capacity of that. Is that what is this? That is a rating or as a C rate or the discharge rate at which this battery is designed. That now, if you'd like to understand more about theory, it usually you will find in the PV system Seton see 2,000. Seat then means that this is Charles time is 10 h see 20. It means the discharger time is two. When t hours see hundred means we are charging in 100 h. Now instead of ten, if we have five, means, 5 h for 4 h, and so on. Now, if the number on the left side like here, e.g. one, C means 1 h equals similar to c1. E1, see similar to C1. Now what about this one? Juicy? Juicy means that we are going to be, The time will be if the number on the left side, it will be 1 h divided by this number. So you can see here on the left side you can see 1 h divided by two gives us 30 min. 1 h divided by three gives us 20 min. 1 h divided by four gives us 15 min. Okay? Now on zero, on the left side we divide by hours. On the right side we multiply by hours. You can see 2 h, 3 h, and so on. Now, this category here representing what the representative slow charging and slow DC charging. You are charging in 10 h or in 5 h slowly, in 20 h, in 100 h, very slow charge. However, the batteries which are in 1 h 30 min, this is a very fast charging muscle. Now you have to understand that Zack commonly used in vivo system. You can find theta1, C20 and see hundreds, which is a slow charge in the new, with the batteries, like the lithium batteries, you will find, hi, this is Charles rate of maybe one or two. C means it can charge and discharge in 1 h or less than even one. Okay. 25. C10, C20, and C100 Batteries: Now, since we talked about with Zach pass, those are batteries and we talked about SU rating. Now let's understand more about them. We have here as Heaton see 2,000 solar batteries. All of them are 150 amps per hour. I would like to convert between them. So as you can see here, C ten, what does this mean? It means it will last for about 10 h. That lowest to discharge time is 10 h. See ten, 10 h. Since we are talking about 10 h, if you divide 150/10 hours, it means I will supply to a load of 15 amperes and it should be discharged within less than 10 h. They've acted otherwise, the battery life for the start decreasing. And what I mean by this, if you e.g. supplying current to certainty and bear loot, that this is charged rate will be faster than 10 h, e.g. it will be 5 h. 5 h. This fast or discharge rate. More than that one which is designed for it will lead to decreasing in the battery life. So C then it means 10 h. I should not decrease beyond this value, not less than 10 h. However, you can e.g. disassociate in 15 h or 20 h, or 100 h as you would like. But the most important part is that you don't charge it less than 10 h. The one which is designed for similar to, see 2020 means 20 h. So the load here will be 7.5 amperes. 150/20 hours will give us 7.5 and bear against this one should not be discharged less than 20 h. So if you look at this repositories, let's say Go and CC hundred first. So you can see the faster the battery gets a discharge it from the time that is designed for, the lesser energy you will get out for it. Get out of it. Seton is known as to be fast. This is charged. Compared to what? Compared to C20 and see, all of them are slow discharge. Compare the two C1, C2 to C1 and C2, C3, C and so on. However, converted to each other, see then is the fastest discharged compared to C20 and C. So Seton is known as fast as is the charge C20 medium discharge and see hundred, which means it will last for about 100 h or supplying to a very small load of R1, 0.5 ampere attributed as a slow this HR. So what you can see here is that we have Seton C21, TNC hungry. Now a very important thing is that you have to understand Seton can act as a C 20 and the Act as I see hundreds. So it means I can discharge in 10 h, 20 h, and the hundred hours, it will not affect the battery. However, see 20 can act as a C hundred, but cannot act as a seat. And if you try to discharge in 10 h, similar to C, then it will lead to decaying or decreasing of the battery life. Also see, 100 cannot act as a C20 or a C ten. Okay? Why? Because it can not be discharged in Alpine less than 100 h. That's why I see ten, in my opinion, is considered the best option best option combined sewers to C20 and see home. Now, let's talk about what the seat and C2 and 1,000 applications. So you have to understand that you will find in the market Seton C20 and see hundred other solar batteries. However, my own recommendation is that you use only see ten. And if you don't find your seat and use c2e. Now you can see that Seton are always recommended for solar and industrial applications because they have the person they're charging and charging rates compared to Z 20 and see homeless. Now as the high load users battery power, it can deliver more energy in a short time. This can give us more energy large, embedded in a shorter amount of time, say 20 however, are not preferred because the excess can draw in will lead to reduce its life cycle, as we talked about before. Because it cannot be discharged in a time less than 20 h. Now when our outage of power is less and this discharge, if time is long, we have a very small loop combined to see it. And then we will start using C20. C22, our usual use in a UPS system when the battery power is less and we have a small loads such as bulbs or fans that can be tolerated. When it comes to solar installation, Seton is usually also highly recommend that batteries, Seton, Seton is the most realistic and close to that literally electrical consumption of 24 h. Remember, we are discharging a part of our poetry during night. So it is realistically can then ours is enough to provide electrical power at max. However, see, hungry is a very, very slow this each of which is not recommended unless you have a very small load. And at the same time you are experiencing several days of autonomy. Autonomy when you don't have more than three days, if you don't have sun for a very long time, you can use C hundred. However, you can see that c turn can do the same function as C and C. So C ten is so B, or the highly recommended battery. Now let me tell you why C2 and it can be used as as I see it, C20, e.g. or a C tan can be used as Z 20 or 100. And as an example, we will see C292 right now. It will help you understand the idea which I'm talking about here is that lead acid battery, as I remember, it is an AGM battery. So if you look at the electrical specifications which we will learn in the datasheet lesson of the lead acid batteries. You'll find that the voltage goes up batteries 12-volt. This is aspects of one battery. I see 20, but inside the data sheet you will find us. Now is the most important part is the capacity which I'm talking about right now. How many ampere hour? So this one is a C 20, okay? So we will look at here, see 20. So as I see 20, it can give 205 and burrow. Okay. Now, let's look at if the discharge time increased discharge time to Wendy hours as we increase the time of discharge, you can see look at the amount of energy I can take, 205-20010001316. So as a discharge, as time increases, this is George time increasing slowly. Discharge. For that 20 battery, a higher time, more than 20 h, you will get more energy. So you can see we can use EC2 and battery as I see hundred and at the same time we will get more energy. However, if you decide to use a C 20 battery, as I see, ten battery smaller, this is charge times n there. When 2 h, you are discharging in 10 h, you can see that the amount of energy taken is becoming less and less. That's why you can use e.g. as Seton as I see, hundred battery. But you cannot use at Seton battery. But you cannot use as C20 battery as a Seton. But why? Because it will take less energy and it will affect as a lifetime of the battery. That's why if we assume that if we assume that this is Pigs was for 100 e.g. you can see that if we decide to charge at a smaller time, amount of energy start is decayed. That's why you see then is the best option. Then see if you have e.g. C1 legs are lithium ions, then you will go for it. Of course, if you have enough money. And we will compare between the different types of batteries inside the course. Don't worry about this. So I hope that battery capacity, you have understand now is that meaning of the battery capacity and the house at the same charge current or, and bears effect as ampere hour of savage. You can see different times lead to the front and bear hours. That's what I'm talking about. So usually, usually you will find that here. Real life is the ampere hour is not a constant. The value that an hour is a changing depending on the discharge a time. So e.g. if you are if you are designing a PV system and use that as heat and battery, then I'm going to use the value of the capacity, which is on the specs, which is that 10 h. And I will design my system based on this value. Nodes, the other values, but based on the value which is the worst-case discharging in 10 h. 26. Battery Connections: Hey everyone. In this lesson we will talk about the different connections of the batteries. We talked about this before when we had an introduction about PV panels. But now we will also talk about it once more. The first connection is series connection. So in a series connection ZAP all stiff terminal, one battery. It's connected to the negative terminal of the battery, and the voltage will be added together. So we are connecting the opposite terminus of the batteries. Let's look at an example. You can see is this two batteries at 12 0 volt battery with 100 and bear our 12-volt battery and 100 and bear our positive, negative, positive, negative. So in order to connect or increase the total voltage, we will connect this up. All still was the negative of the battery. So now we have a total voltage of a 24 volt. However, you have to understand stand one thing which is really important is that when we connect two batteries in series, the ampere hour will be the same. And bear our hundred, umber, our hundred and bear hour. It will be also 100 and parallel. However, the total voltage will increase. Now, after connecting these two patterns, you will find that we have are all stiff terminal and a negative term in which we are connecting this to the charge controller. And at the same time we will connect to from it to our inverter. Another example here, you can see at 1 v battery, 12 volt, 12 volt. Now, poles, they've connected to negative poles to connect it to negative. Then we have the final positive terminal and find a negative term. These two terminals will be the ones that will go to the charge controller and the inverter. You will also see here that we have three batteries connected in series. So they gave us six volt, the wild lost 12 plus 12. Another example here we can see asics of all to pottery was at ten ampere hour, six volt battery it and I'm per hour connected in series. You can see it's the opposite. Terminals are connected together. All Steve, who is a negative term. So we'll have one final positive and one negative. You can see there are some mission will be 12 0 volt and the emperor will be the same. So when we would like to increase the voltage of the system, that battery system, we connect them in series, similar to the panelists, when we would like to increase the total voltage of the panels, we connect them in series. Now, for the parallel connection, we will have here in a parallel connections are all stiff terminals are the terminals which are like each other, will be connected together. So the positive terminal of the batteries will be connected together. And negative terminal of the battery will be connected together. In this case, the ampere hour will increase, so the voltage will remain constant. But the total M bridge, or the total ampere hour will increase. Like here, e.g. you can see these two batteries, 12-volt. Another 12 volt, you can see posted was both positive, negative was negative, and we will have the final negative and the final step. Now, this what you see here, it means that sensitivity are in parallel. The voltage will be kept as it is. However, the total amperage or the total and bear our will increase. Hundred plus 100 will give us 200 ampere hour. Here is another example, as you can see here, 12-volt revolts and walked all stiff connected with, all stiff connected with positive, negative, negative, negative, negative final poster. You will see that the voltage itself escaped as it is. However, is the ampere hour will increase. As an example, if this one is at ten ampere hour, day number hour, and then impair our what will happen is that the total ampere hour will be so t and per hour. Since they are connected in parallel. Same idea here as you can see. We have a two batteries, six volt battery, six volt battery ten ampere hour, ten ampere hour, negative, negative, positive, positive. So what will happen? The same voltage since they are connected in parallel. However, the total ampere hour increased to 20 and bear hour. Now, when we are having a bigger BB system, we are connecting them in series. And all of this depends on the system itself. Now a series per connection is a combination of both, where two or more sets of batteries are connected in series, then in parallel. So as you can see here, we have 12 v connected with another 12 volt as they are in series. These two are also connected in series. So we will have a 24 volt here, another 24 volt here. Then we will connect this, this string of batteries barrel to this string of batteries. As you can see, negative was negative and bolster was not always positive. This will increase the total ampere hour and serious connection will increase the total voltage. Now if you'd like to see this more practically, you can see is this one which is our BV panel as a PV panel, our batteries. You can see we have two terminals for this battery. We have the ball step terminal, as you can see here. And we have the negative terminal of the battery. Right? Now, let's look at this charge controller. As we said before, this is our charge controller. You can see here two symbols. Here. You can see plus minus representing. And here we have a panel of terminal of the panel and negative terminals of an x. So we can see here. Here we have the negative terminal going into the black one, which are representing the negative terminal of the panels. And you can see the red one which are representing Zappos step of going to the positive terminal of the battery. Similar to Itza batteries. As I read one representing as opposed to if you go here, like here, you will see it's connected to the pole stiff term. The negative, if you look at here, exists connected to the negative of the charge controller. Now if you'd like to see is a charge controller more closely, you will find it like this. You can see here, this is a sample of that BV panel. So it takes one positive terminal and one negative term. So we will take the negative of the bolster, the BV panel. You can see this is both if connected here and the negative connected here. For the battery positive-negative. You can see sample of the battery or stiff connected here and negative connected here. Now, if you have a DC loads, you are going to connect to here. You can see here Paul, the symbol representing D, C loops. If you have the solutes you will connect. These are all negative here and supposed to be a positive and negative in this term. Okay? Now of course is that Charles as an inverter itself will be connected as these terminals here going to the inverter itself. Now, as you can see, it's very clear. Pv panels or seven negative batteries or positive-negative. And this for DC loads is, this is an extra feature. If you don't have any DC loads, you will not need this at all. Now, one important thing here is that you never, never connect a DC load directly to the battery. Why? Because the battery e.g. rigid zero per cent, it does not have any remaining charge. All e.g. beyond the limit, which I don't discharge it more than this. What I mean by this, let's say e.g. batteries, such as lead acid batteries, we use a discharge of 50 per cent. We just use 50% because the capacity of that charge controller of the battery itself. So we don't take any more power or energy than 50 per cent because it will affect the lifetime of the battery. So if you connect this app loads directly to that lead acid batteries, it will keep decreasing this value even I add zero per cent, it will start damaging their battery itself. However, the charge controller always sees a state of the battery. The battery for reaching a certain state, it will start disconnecting this load and prevent damage to the battery. At the same time, if the battery is completely charged, it will disconnect it from the solar panels. Or to be more specific, it will be ads afloat stage. This stage which we are going to discuss when we talk about the pottery psych. Now, let's look at that maximum power point tracking charge controller. You can see here we have that batteries, host of negative of the battery and both of negative of that PV panel. And if we have a DC load, okay, this is not what we connect to the inverter as this is just for a small loop. Okay? Now before we go to the next slide, now we have to see here, you can see we have three bulbs here. Okay? The green LED, yellow, red, and blue. Let each one of these representing a float state, absorption and bulk. Now z is representing what? This representing the three stages of a charging a battery. So we are having a bulk stage, then we have the absorbance absorption stage, and then we have the float stage. Now, when we are going to discuss, I would like you, when we discuss this in another lesson, I would like you to remember this float, sorption and park. So when you are looking at this bulb, you will understand what is stage overcharging is your own battery. Okay. Now here is another example you can see here at 12 volt, this is not add. This one is not an assault or battery or a deep cycle battery. This one is a car battery. You can see here what I would like to mention here. You can see when we connect the red together or pull stuff together and together, we will have seen voltage, but the amber or the amperage will increase. You can see here 500 ca plus 500 CA give us 1,000 z. What does see a mean? It means cranking and cranking and this is used in car engines or the car batteries for salting is a car. Now if you look at here, we have negative connected with positive and we have final narrative and final poster. Okay, so we connect them in series. So the total voltage increased ands account remained the same. Here we should be CAA or cranking and bears. So for your own knowledge, this is not related to BV systems. See air representing Zach cranking, amps or the cranking and bears. This represents the exact rankings or engine starting batteries, service civic type of batteries that is used in car engines. Now one important note that you will understand in the next lessons is that we don't use the car batteries in BV systems. Don't ever try using car batteries. In the BV system, we use one type of batteries called the deep cycle batteries, which we will discuss in another lesson. 27. Cycle of a Battery and DoD: Hi and welcome everyone. In this video, we will talk about it as a cycle of the battery and DoD or depth of discharge. So the life cycle of a battery representing number of charge and discharge cycle that it can complete before losing its performance. So any battery has certain life cycle, or how many cycles it can give before it starts to lose its own performance or becoming debt. And each one cycle, when I say one cycle of battery, charging, charging the battery, then discharging this battery. This complete cycle representing one cycle of battery charge plus charge. Now, as you can see, charging and discharging the battery representing one complete cycle. Example. As an example here, this is charging a battery. You have a battery here, which is already charged at 100%. Now, if you start discharging this battery from 100 per cent to 20% and then start charging it from 20 per cent back to 100%. This representing one complete cycle. So that is a definition of a cycle of a battery. Now, each battery has its own number of cycles, e.g. if you find e.g. the lifetime of a lead acid battery can be e.g. a, 1,000 cycles. So what does this mean? It means that this battery or the lead acid battery can give 1,000 cycles before it loses it to performance or it becomes dead or required replacement. 1,000 cycle represent 1,000 times of charging and then discharge. Okay? Now, another important definition in batteries, really important, which is important in the design of the PV systems. It's called the depths of the sea charge. So what does that depth of discharge mean? It indicates the percentage of the battery that has been charged relative to the overall capacity of the battery. So before we talk about this, before we look at this figure and let's understand depth of discharge. What I mean by depth of discharge of 50 per cent. Depth of discharge 50%. It means that I can charge my battery 50 per cent of it. So let's say e.g. let's say we have 100 and Baer Our to understand this idea. If I'm going to design my BV system based on a depth of charge of 50 per cent. It means I can take only 0.5 multiplied by 100. It means I'm going to take only 50 ampere hour in each cycle, in each cycle of a charging and discharging. So what I mean, one complete cycle in this case, one cycle will be equal to a charging, okay? Charging from, from 50% to hundred percent. And then this is charging from 100% to 50 per cent. So this is one complete cycle. At depths of DC charge 50 per cent, whereas 4s2 using 50% of the capacity of the battery. Now, let's see another example. Let's say you are talking about with 80 per cent of the same battery, this 100 ampere hour. So it will be 0.8 multiplied by hundred and bear hours will give us AT ampere hour. So I'm going to take only energy from the battery AT ampere hour. So it means that if it is 100%, I'm going to DC charge it up to 20%. Why? Because you already took 80 per cent of the battery. State of charge, or how many energy remained in that battery is 20 per cent. Then I'm going to charge it again from 20% to hundred percent. This will represent one psych. So this one cycle based on a 50 per cent depths of this surcharge and this representing 80 per cent depth of discharge. Now the question is, why depth of discharge important? Why exhausted? Why don't I just take all of the energy inside the battery itself. Now you will find is that the higher depth of discharge, the more energy you are taking from the battery. High discharge. High discharge leads to lower amount of cycles. Now if you look at any data sheet of any battery or the specs of any battery, you will find e.g. let's say this is a figure from one of the battery types. Now, if you decide to design your own system by discharging it at a 50% only, you will be able to get from the battery, let's say a par with 3,500 psych. So this battery will be, will give you 3,500 cycles through its own lifetime. However, if you decide e.g. to discharge it at 80 per cent, you will only get 2000 cycles. If you decide e.g. at assertive present, you will get more cycles, which is 6,000. Okay? That's why it's a selection of the episodes source is important. It gives you that estimation for how many cycles. And this cycles will be equivalent to how many years as a battery will remain. So as you can see, depths of this HR, it means I'm going to take 80 per cent of the battery. I'm going to charge 80 per cent of the battery. Now, this is a really important part of it for you during design. That most common patterns that we use in BB systems are lead acid batteries and lithium ion or lithium ion phosphate batteries. Lead acid batteries that recommended depth of discharge during design is 50 per cent. So when you are designing it, you will be designing based on the 50 per cent. However, for something like lithium ion, you are going to recommended depth of discharge is 80%. However, you will find that some other modern lithium ion batteries can have a depth of discharge 80-95%. And chop class batteries can reach hundred per cent depth of discharge. Now how can I know this value from that data sheet or the aspects of the battery? Okay. Is there is no one correct solution? All it depends on the designer or the manufacturer of savage. But in general, most likely lead acid batteries are designed at a 50 per cent depth of discharge. That lithium mine at 80% depths of this HR, this is a recommended values. Now, as you can see here, the higher depth of discharge that I use in my own PV system that lower the battery life. So as you can see, 50 per cent so resolves on 500 cycles, 80%, only 2000 cycles. Now, since, uh, we told up our depth of discharge, we need to talk about the reverse, which is the state of charge. Now state over the child is the opposite of that depth of discharge. State always charge is a percentage of the battery capacity is still stored and available inside the battery. E.g. if you having an eight kilowatt hour battery with a depth of discharge, 75%. It means I'm going to take 75% of the energy. 75 per cent of eight kilowatt remaining energy will be 25 per cent or two kilowatt hour. So as you can see, depth of discharge, how much energy I can take from the battery state of charge, how many electrical energy Raymond or energy stored inside the battery itself. So this is an example that will help you understand. So if you look at here, this is a battery, let's say talk about our mobile battery. Mobile battery, e.g. if you look at here, at this part, you can see is this pattern is completely charged it, right? So since it's completely charged and we say it's a state of recharge is 100%. When it is at, at this level it will be 0%. Or SOC, or the state of charge is zero per cent. The depth of discharge is a reverse here. At this level, hundred percent of state of charge. And we didn't take any amount of energy. So it will be zero per cent. At this level, we take the hundred percent of the battery. That depth of discharge will be hundred percent. Now, why depths of this discharge is important? Because it will give us the usable or rail capacity of the battery itself. Okay, So if we have 100 and bear our battery, lead acid. Lead acid. We are using FFT percent depths of the church. It means that we can only take 50 amber hour. This is the real or the useable capacity of the battery itself. If you are talking about something like lithium ion. And we said that the depth of the charge is 80%. It means I can take a t ampere hour from the battery. This is a rail or the useable capacity. So Anzac specs itself, it is 100 and bear hour. However, in reality, I can only take for lead asset 50 per cent on lithium ion, 80 per cent. Now let's delete this. And since we talked about that depth of discharge or that state of charge, you will see this table as you can see here. Now, how can I know the state of charge of that battery itself? This can be done using the state of Georgia. You can see at 100%, we are talking about aspects of a six volt battery. If I measure the voltage across it, it will be 6.42. So this is a six volt battery. At 100% charge. It will be 6.42 volt. At a 0%, it will be 5.8 to value. Okay? So this value is important why it is important? Because they can be used inside the charge controller itself. E.g. if we reach a certain level, we will disconnect that that load from the battery. So let's say e.g. my own batteries design that 50% depths of this charge. So when the state of charge reaches that 50%, which is equivalent to 6.12 volt. Inside the charge controller itself. I will say or insights the inverter, not the charge controller. Inside the inverter, I will say disconnect is a load at 6.12 of the voltage measured across the battery to prevent any damage to the battery. So you can see here that 0% also Volta is the final discharge watch and we shouldn't decrease beyond it. Others, otherwise, the battery life will decrease and the battery will be destroyed. So these two values are important as zero per cent. We have also to add it to the charge controller, to the inverter to prevent any absorption of electrical power. Beyond this one, auto is a battery will be destroyed. If we are designing the system at a 50 per cent, then we will add this value to the inverter to disconnect any loads at this value. As you can see here, if this voltage, this voltage will be added to the settings of the inverter to stop taking power whenever we reach zero per cent to prevent any kind of damage to the battery. 28. Deep Cycle Batteries and Car Batteries: Hey everyone. In this lesson we will talk, or in this video we'll talk about that deep cycle batteries and the car batteries. So let's first talk about the deep cycle batteries. At deep cycle battery is a lead battery or a lead acid battery designed to provide a sustained power over a long period and run reliably until it is 50 per cent, discharge it or more, at which point it needs to be recharged. What does this even mean? Now remember that epsilon, this is Charles, as we talked about. We said in lead acid batteries, we don't and increase the depth of discharge or the amount of energy beyond the 50%. So we can only take 50 per cent of the battery, then start recharging it. Now, what you will see that here it is designed this type of batteries, which is a deep cycle batteries, are designed to regularly deeply discharge it using most of its capacity. As an example, lead acid battery here we are talking about lead acid battery, but this is not necessary. Lead acid, it can be lithium, it can be nickel cadmium, it can be any other time. But what we would like to learn is that it is regularly daily, e.g. every day, every couple of days, it is regularly deeply discharged using most of its capacity. So if we're talking about lead acid battery, it is almost every day. This has charges. We take we took 50% of its energy every day. It is regularly deeply discharged, e.g. or lithium ion can be every day, 80% is taken out of the lithium mine. That deep cycle batteries are ideal for applications that require more than a quick stat, such as solar system. So they are used in the solar system deep cycles, which are deeply decisions regularly DOB this a charge. Unlike other patterns which is used as a quick starts, such as in car batteries. If you look at here is the starting batteries and the deep cycle batteries. So you can see the starting batteries and deep cycle batteries starting. But you can see is that blade to here is very son insights that batteries, however, here in the deep cycles they are very sick, very sick weights. As you can see here, that weight of this deep cycle is very large compared to the starting patterns. Starting batteries are used in cars. Deep cycle battery are used in BV systems. Now, solar deep cycle batteries. Now, as you can see here, if you look at this battery, e.g. 12, a volt 260 ampere hour battery, right? But if you look carefully at it from the future green technologies, this batteries from future green technology. You can see here it is f, deep cycle, battery, deep cycle, but it means this one is designed for systems are like BB systems. This one, e.g. you can see this one is a lithium ion, lithium ion and phosphate battery. You can see it is that we're volt 100 American see long life, deep cycle. Look at this one. This is an AGM or absorbing glass mean, which is one of the types of lead acid batteries, a deep cycle battery. All of them. What is the common between them? Deep cycle. So the deep cycle are used in solar energy applications because they are designed to give large amount of cycles, large amount of deeply discharge it cycles every day. Now, what's the difference between car and deep cycle batteries? So we saw that car or the starting batteries have thin plates that deep cycle, but to have sick blades. That car battery is designed to provide large amount of energy in a short period of time, which is enough to boost the engine or powers engine until the alternator takes over. So the Otherland to give very large energy in a very short time. However, that solar batteries, they provide lower amount of energy for a long period of time. Because we have our system which is our home, we need electrical power for a long time, 10 h, 20 h, and so on. However, car battery gives very large amount of energy in a very short of time, parsed, parsed of energy. So a car, but it gives high Canon for a short duration. Our solar or gives like a bus will give a low current for a long duration. As you can see here, they represent as a starter battery in the form of a rabbit that gives we parsed of power, which is not good for slow and steady power delivery, similar to the BV or deep cycle battery. So z are used for giving large amount of energy in a short time. This one are used for giving a continuous power or a slow amount of current or low amount of current for a longer period or a large duration. So this one is considered as a rabbit. This one is considered as a total. Now, can we use car batteries in a solar application? Is a buttress will not last long and they are likely to fail after just a few days. And some people, e.g. after a couple of months, as you will see, will be that because they are not designed to give deep cycle or discharging for a lot of times deeply the source for a lot of times. Can use a deep side to start a battery? No, you can't. Why? Because deep cycle provides low amount of current in a long duration. So it will not give sufficient current to start a car engine. So each one of these designed for a certain application. As you can see here, same plates and SIG blades, startup batteries or car batteries and deep cycle batteries. You can see the episode stores. They are cd with a short spikes. So this is charged quickly, then it Charles quickly, discharge quickly and charge quickly. And you can see very small discharge combined to that deep blue cycle. You can see a long duration. You can see a longer duration from here to here. And the bleed is a charge. Here. This is a very short duration. This one is a longer duration and the bleed is a charged. Okay, So each one has its own applications, so don't ever use car batteries in BV systems. Now, if we look at another thing here, remember the depths of the sea charge that we talked about before? This one. This one is at depths of charge for one type of batteries. Here, if I remember is I lead acid batteries or a flooded lead us in. But if I remember correctly, you can see here are 50% discharge. It can give out once I wasn't 150 cycles. If you use a lower discharge, you will get more and more cycles. Now, let's look at that car battery here. If you look at a car battery, you will see that this is the capacity and number of cycles. So you can see is that capacity will start in decaying through our time after just it can reach 80 per cent after about 750 cycles. So it gives a very small amount of cycles, convert it to the deep cycle. But deep cycle, you can see at a 50 per cent gives oneself zones like here. You can see that as time passed, it will give maximum of 400 cycles and it will be that that's why you don't use a car batteries or start or batteries inside. That'd be the system. Now, one important note here for you as an electrical engineer or a solar engineer, that there are many people who sold solar batteries as car batteries or not, not exist. Many people sell car batteries as a solar batteries. They take the starter batteries and solid as if it is a solar batteries. Why? Because car battery is cheaper than a solar battery, you can see some plates and it gives a low amount of cycles. So it is cheaper than a solar panel. So that's why him Vinny pupil sells a car battery as a solar battery to make profit out of it. Now, how can you distinguish or differentiate between our solar battery and a car battery? You will find that the assault or battery, since it has sig plates, it will be heavier than car batteries. Now, these loans or car battery as a solar batteries and put incisors care-of address since it is a light, lighter batteries and solar batteries. So the add inside the car batteries, stones, concrete, and any other materials to make it heavier than, hate, to make it heavier lines or real solar matters. So as you can see here, this is a car battery, this one is a car, but this one is a carpet, but they are sold as, they are sold as what? They are sold as a solar batteries. So you can see we have this in place of the lead asset, but the ad also materials such as stones, concrete here as you can see here. You can see the battery and the ad stones and other materials to make it heavy, like the real solar battery. So be aware of any one bilayer from the manufacturer or the seller is that you are buying from it the batteries. Because many of them may sell fake batteries. So you have to make sure that the batteries that you are obtaining a real batteries. So in this lesson, we talked about the difference between a car battery and a solar battery. 29. Specific Energy and Specific Density of a Battery: Hi, and welcome everyone. In this lesson, we will talk about a very simple but efficient characteristics of BEV battery or a solar batteries. This is a specific energy and specific density of a battery. So what does a specific energy and what's the specific density of a battery and all it's important. Now specific energy, since we are talking about energy representing how much energy a battery contains in comparison to its weight. And typically expressed in how many watts hour, which is energy per kilogram. So how much energy can it give for each kilogram of this metric? That volumetric energy density, or the energy density of the battery, or the specific density of a battery is a measure of how much energy about three contains in combatant to its volume. So it is how many hours? Bare liter. So this one specific energy. How many, what hour it can give or how many energy for each kilogram of this pattern. The specific dusty representing how many energy, how much energy bear liter or as a volume. So this is as that weight, and this one is as a volume. If you look at this figure, this figure is really important. So it shows us different types of battery. Here I'm concerned with lead acid batteries, nickel cadmium batteries, and lithium ion batteries. You can see here is a volumetric energy density. What our per liter and the x axis representing their specific energy than say, how many watt hour per kilogram. As you can see, lithium ion, which is the most expensive option, which is x abundance of Zahn, nickel, cadmium, and lead acid. You can see that Z are lighter in weight. Why lighter in weight? Because you can see it has higher what? I'm beer per kilogram, moles and nickel, cadmium, and lead us it has an example, let's say take this value and things as value and take a random value here. So e.g. here, let us it, let's say 50 watt hour per kilogram. Nickel cadmium gives us e.g. it's 75. What? Our patient kilogram lithium ions gives us more energy, or let's say 180 watt hour per kilogram. So lithium ion is lighter in weight, gives them more energy for each kilogram. Now, for the volume, the same ID you can see if we go over here, here, but asset, nickel, cadmium, and lithium ion and gives us more energy per volume or Bill liter. So what does this mean? It means if you can put a lithium ion to lead acid battery, e.g. you will see that lithium I have a very small size, very small weight, a very small volume compared to something like let us, let us e.g. it to size can be three times. Its size can be three times that. Let lithium ion batteries, e.g. if someone can be e.g. let's say 10 kg, equivalent can be, let's say 50 kg. It is larger in volume, larger in weight, converted to lead acid. But lithium ion battery. If you have a limited space in your own home or reasons allocation. And you would like to get higher amount of what our forms a buttery and you have a limited space, then you will go for lithium ion. If you don't have, if you don't have any problem with the space, you can use lead asset and nickel cadmium batteries. Now, this is not only the factors that will affect the election, but that duration of the BV system. That how much money do you have when making our buildings as VV system? All of these factors that we will talk about in the next lessons. 30. Self Discharge of a Battery: Hi, and welcome everyone. In this lesson orange, this video we'll talk about the self and this is charge of a battery. What is the meaning of ourself with a charge of battery? Charge of a battery is a phenomenon that occurs in batteries, in which is the internal chemical reactions that's happening inside the battery, would reduce the amount of energy or stored charge of the battery without any connection between the electrodes or in external circuit. What I mean by this. So if you have a battery like this, which is a charge that 100%, and you didn't connect disease but to any external circuit, you didn't connect it to. E.g. an inverter is connected to anything you just to lift it at 100%. You will find that this battery, as time passes, you will find that the percentage of that amount of charge stored, it will start decaying with time. Instead of 100%, it can be 90% or whatever is the value without using energy inside it. Now why is this happens in do a phenomenon called cell for discharge? Because when you leave a buzzword like this, that is internal chemical reactions that happens inside the battery itself. These chemical reactions will reduce the amount of energy stored inside that battery. Now of course, this will affect something which is called the shelf-life of batteries and cause them to have less than a foliage charge when used. Now, we will understand what does the shelf-life mean in the next lesson. Now, as you can see, e.g. this figure representing and energy stored or the sulfur diesel charge versus storage is time for one of the types of the lead acid battery. See if I remember it is an AGM battery. Now as you can see here, look at here exactly. You can see on the left side, we have a state of charge in a percentage, how much it is a chart for. So we started with 100 per cent. So the state of a charge is 100%. It means that our battery, It's completely charged. Now, you can see on the x-axis we have the storage time in Monsters, hundred percent and this monsters. So as a storage amongst increase, as time passes, you will find that the status jaw starts decaying with time. It starts decaying with time, as you can see here. So e.g. if you look at this curve, e.g. this one, you will see that e.g. after 15 months is the state of Utah decade from 100% to about 30% without using the battery at all. Okay, only by leaving it as it is on the shelf. It will have the cell for the surcharge and its charge will decay with time. Now as you can see in this figure, we have 12344 different curves that we will find. This curve is found in the data sheet or the specs of the battery itself. Now, as you can see here, that we have different curves at ten Celsius degree, at 25 Celsius degree, Celsius degree, and 40 Celsius degree. Now what you will notice here is that as the temperature increases, as temperature increases, you can see 1025 salty forth. As the temperature, temperature increase, the esophagus, the charge increase. If you compare the sphere of them, if you look at any, let's say after six months I exist. You will see that the ten Celsius degrees are storing of the Patriot at ten Celsius degree have about 90% of its capacity. If you store it at, at, at 25 associate's degree, you will find here exactly where. You'll find it exactly here, as you can see at this point. So you can see it is a powered less than 75, let's say 70% or whatever is the value for the third dissociates degree, let's say 65 at this point. And for 40 Celsius degrees, you will find about 45. So as you can see, as temperature increases, the self, this is charge increases. That's why the cold temperature slows down. It's a chemical reaction which leads down, which leads to slowing down the sulfur does the charge of a battery. That's why if you notice that in our homes that we have extra batteries, extra small buttress that we use in a TV or a receiver or whatever it is. These extra batteries, we put it inside that refrigerator. Now why do we do this? Because the cold temperature reduces that chemical reactions and increase the lifetime of this battery. 31. Shelf Life, Cycle Life, and Calendar Life of a Battery: Hey everyone. In this video we'll talk about three important definitions. That shelf-life, that cycle life, and the calendar life of a battery. So let's just start by shelf-life for buttery. And it's pretty clear from its name. Shelf-life. It means we are talking about Zao life of the battery when it is put on the shelf without using it, storing it on a shelf, without using it at all. So the shelf life of a battery refers to how long it can sit on the shelf before needing any requirement of a charging or becoming expired. Now you have to understand that all batteries suffer from sulfur. This is charge over time even when they're idle. And this what we talked about in the previous lesson, when we talked about the cell for discharge of batteries due to the internal chemical reactions. So this, the chemical reactions affect the shelf-life. So that shelf-life of a battery depends on the size of this battery. That chemistry is the type of this battery itself is it, is it lead acid batteries? Is lithium ion is at nickel, cadmium, and so on. And also it depends on the manufacturer of the battery who built this. As an example, you will find that nickel cadmium batteries have a shelf life between 1.5 to three years. So it means that I can put this batteries on a shelf without touching it, without doing anything to it. Between 1.5 to three years, the lithium ion have a shelf life of a three to six years. Now considering that lead acid batteries, most of the lead acid batteries should be charged or have a maintenance every six to nine months. Combated of course, to something like nickel cadmium and lithium battery. Susie need three quantity charging and split maintenance, especially that flooded lead acid batteries. Now let's talk about the second definition, which is a calendar life of a battery. The calendar life of a battery is a period from the date of protection to the end of life of batteries measured in years. And when I say come the live, it means e.g. let's say if we talk about ten years, I exist. This means that the battery will last maximum time of ten years. So that from that day it will, it is produced to the end of its lifetime. The maximum time according to the manufacturer is ten years. This is Kevin, the life of a battery. If you use it or you don't use it or anything, they will have maximum of ten years. You cannot exceed this time. This is a manufacturer, calendar life. Now this, this amount of years, which is the defined the poison manufacturer itself, can change depending on the temperature at which is this battery or restored. If they are stored at a high temperature, this temperature will lead to decaying or degradation inside the battery. So finds that with the increase in temperature, the rate of chemical reactions inside the battery itself will increase. The increase of this rate will lead to increase in the degradation of the battery. Battery will last lower amount of years. That's why higher temperature is also is harmful to the calendar life of the battery. So the most important part is that we need to store our battery in a lower temperature because it will lead to increasing its own lifetime. Now is the final definition is a cycle life. So we talked about shelf-life. How many years that showed I can put my own battery on a shelf without needing overcharging or before the battery is expired. The calendar life representing how many years since up production to the end the life of this battery, how long it will last even if I don't use it. The third one, which is a cycle life of the battery, which are representing how many cycles of a charging and discharging. So each one complete cycle representing a charge and discharge as we talked before. So how many cycles does the battery can undergo before its capacity degrades to 80% of its initial capacity. So like Calendar life, higher operating temperature lowers the cycle life of the battery. So let's see what I mean by this. So each battery can give us a certain amount of cycles as we did before or as we said before, when we talked about depths of this surcharge, If you remember, we said that the bending modes, the depth of discharge, we will have a certain cycle, let's say 1,000 cycle or 1,500 cycles and so on. Now, the same idea here. This is what we call the cycle life. We say exactly when it reaches to 80% of its capacity. So if you look at this figure, that we started at 100%, And also I mean by 100%, it means that when I charged it, it will reach 100%. When I charge it. Now after time passes, as our, as time passes, you will find that the remaining capacity, the higher cycles I use this battery, or higher cycles taken from this battery. Capacity of the battery will start decaying. Now as the temperature increase is educating will increase with time similar to shelf-life, similar to the calendar life. Now, as you can see here in this figure, this figure representing how many cycles. So let's say e.g. I. Charge it. Soak up our let's say this one, e.g. or not this one. Let's look at one which is more clear. Let's say it's this one, which is the hungered Celsius degrees. So I am using my own battery at 100 Celsius degree. Okay. Now, after it charging and discharging my own battery for 200 times, what will happen in this case, if you go up here, you will find that at this instant, my own battery is now 80% of its capacity. So after using it for 200 cycles, 200 cycles over charging and discharging, what will happen is that my own battery is not now 100% battery. I only can now use 80 per cent of the initial capacity. So 80% of the initial capacity, it means that if I am going to discharge on my own battery, I'm going to solve it from 80% to like 50 per cent. If I'm talking about lead acid battery, then I'm going to charge it from 50% to the hundred percent, which is the 80 per cent of the battery. This is the new capacity of the battery. So after using it for several cycles, after more cycles is taken from it, It's capacitor will start degrading, or the capacitor will start decreasing with the number of cycles. That's why is that temperature at which we use our buttery is really important. So the lower the temperature, the lower the reactions. And at the same time, it will give us more higher lifetime. So e.g. if you look at this figure to apply the cycle life of a battery, you can see 200 cycles, okay, Joe, hundred cycles. This standard cycles gives us 80 per cent. So if we are using our pattern at 100 Celsius degree, the cycle life will be 200. If we look at the second at eight is us as degree. Here, you will find that number of cycles that I will take, it will be about 450. This is a cycle life of the battery. So cycle life at 100 Celsius degrees is 200 cycles. And it is also degree, it will be for hunger and 20, and so the rate at which is a Padres, this chart shows also affect this Zan life of the battery. So what I mean by this is that fast does the charging rate, higher rate, faster charging rate to lead to reduce the cycle life of the battery as it causes mechanical damage and degrades the electrodes observatory. Of course, this charging rate depends on what the battery is designed for. If it is a C ten, then you don't charge lower, faster than 10 h. If it is C hundred, you cannot discharge greater than or less than 10 h or faster than 10 h. That's why Satan is the best as we talked before. Now it was a depth of discharge and the maximum state of Georgia attended by the battery also affected the life of the battery. So we talked about the effect of Debs of the surcharge, which says that if it is at 50% or 30%, it will effect as this amount of cycles. Again, again to make everything clear for you. So when we talk about number of cycles, number of cycles in the curve of depth of discharge. We were talking about the cycle life of the battery. How many cycles I can take from the battery at a certain depth of discharge. After which the capacitor will be less than 80%, ends up. Butters will need to be changed. All you need to work at a lower amount of fluids. That was a maximum state of charge attended buys a button saying this is charging and charging also effect the effect of depth. So we said it will vary with the battery chemistry we said before is the lead acid batteries 50 per cent, lithium ion, 80 per cent, and so on. Now for maximum life cycle, life for nickel cadmium batteries or the nickel-based batteries. We need frequent deep discharges for maintaining their capacity. And z should be targeted towards their fall instead of a charge to prevent the memory effect. What I mean by this, it means that the nickel cadmium battery, the knee deep discharge, and then z should be charged at 200% capacity. The ability to charge it and then charge it to the 100% of the capacity. Why? Because if we don't do this, we will suffer from something which is called the memory effect in buttress. This will lead to reduction in the capacity of the nickel cadmium batteries. So what is the meaning of memory effect? We will learn about this in their nickel cadmium lesson. In the case of the lithium ion, the higher the state of charge attend during charging is Alyssa is the life of the battery, and deep discharge on the lithium ion reduces their capacity faster. That's why if you look at the lithium ion e.g. in my pilot batteries e.g. as our recommendation is between 30% to like mine two per cent in this range. So if you remember that in order to extend the life of that mobile battery, you need to not reach 100% and not reaches as 0%. You will have a medium range, 30-90%. You keep the battery in this range. Now of course, not all lithium ions have the same effect. I believe that lithium ions, there are some lithium ions inside or lithium batteries in general, in the market, which you can reach depths of Josh hundred percent. And z can be fully charge it and fully charged fully discharge it. And at the same time gives us 10,000 cycles, e.g. so, yes, not all of the batteries have this effect. Not all the lithium ion, but just have this effect. This depends in the end or at depends on the type of batteries, the manufacturer. And as the technology that we have right now. 32. Lead Acid Batteries: Hi, and welcome everyone to this lesson. In this lesson we will talk about that lead acid batteries. So as a first time, which we are going to discuss the lead acid batteries, which are really important in PV systems. And we also are going to discuss other times in other videos. The lead acid batteries are considered as the most commonly used the type batteries in the photovoltaic systems. Now why is this? Because the biggest advantage of the lead acid batteries is that Z have low initial cost or they have low price pair and bear our or for each battery. Now, z is types of deep cycle batteries is the lead acid batteries has been used for a very long time since 18s. There are four main types of lead acid batteries that we use. Flooded lead acid batteries that sealed lead acid batteries, or we can call them evolve regulated lead acid batteries. And it's all very related. Lead acid batteries are divided into several types, such as e.g. their EGM or ZAP. So big glass made batteries and let carbon batteries. Where I've also that you blurs obese at V, lead acid batteries. And the top companies that are used to manufacturers this type of batteries are chosen. Data and crown battery. That was the biggest advantage of using this type. As we just said, it is the cheapest the type of batteries, however, is our biggest problem with lead acid batteries is that they have low depths of charge. If you remember that we said that the maximum depth of discharge, the maximum recommended depths of this, the charge inside that lead acid batteries. We said it is 50%. If you remember from our previous lessons. And it has a shorter lifespan, 5-10 years. It our shoulders a lifetime 5-10 years. You need to replace them a lot during the construction of the PV system. If the PV system remain for several years, e.g. you may change them three times, four times, five times and so on depending on the batteries itself. Now, their efficiency, of course, we have since we are talking about conversion from chemical to electrical and then from electrical to chemical energy. It means that we will have some losses during this process. So the losses here inside is the lead acid battery can range of between 85% to 95%, which will need to consider during the design of our PV system. Now another thing is that this value changes depending on what? Depending on the quality of the battery itself and the manufacturer itself. Now, the lead acid batteries, as we said before, when we talked about that specific density and the specific energy, volume or volumetric energy. We said before that the lead acid batteries have large volume, bear ampere hour and large weight per ampere hour. So z are considering consider the as heavyweight, which will make them difficult to transport. They have lower warranty period light as n, e.g. as our patterns such as lithium, lithium can survive for 15 to 20 years. Zao reliability of the lead acid batteries is that is great for resolving grid solar systems and as an emergency backup storage in case of a power outage. Now, let's start by the first time of lead acid batteries, which is a flooded lead acid batteries. That one which you see here is a flooded lead acid batteries. How did I know that this one is a flooded lead acid batteries because you can see here is this caps, this one, this is called as a filler caps. So from here, I knew that this one is a lead acid battery or a flooded lead acid battery. So this one is the oldest and the most basic type of batteries. Where's the electrolyte in or the asset inside it is in the liquid form. Now was a battery uses a chemical reactions between the left and asset to store energy. Is acid used here is H2SO4. Until ten to 12 years that goals are flooded. Race was the most common type deep cycle batteries. And they're still used in some of the large of grid system. Now, there are other types such as lithium ion batteries or the lithium iron phosphate batteries, as there is also that flow batteries, nickel cadmium batteries, mini types that we will talk about in the course. Now, during charging and discharging of flooded battery, volatile gases are produced and are vented out of the battery. So this battery requires the good ventilation because it gives volatile gases. So as you can see right now, require ventilation and they require regular maintenance, which we'll talk about in the next lesson. Now was alive a lifetime of life span of this type of batteries can be 5-7 years. It can also go down to two years for the cheapest and bad quality. But batteries and can reach more than ten years for the high-quality option. So it depends on the manufacturer. There is no one correct solution or one correct value. Now is a life-cycle. There is a range of how many cycles this batteries can get. 500-1600, again, just depends on that battery type, the quality of this battery, that depth of discharge, operation temperature, and many other factors. Now, I would like you to remember e.g. 110 and bear our 12-volt battery can cost around $340. I would like you to remember this number because we will need it in the future. So 110 and bear, our 12-volt from the flooded is $240. This is considered the sheep compared to other batteries. Now let's talk about the components of the flooded lead acid batteries. So as you can see here in this figure, we have a flooded lead acid battery. And you can see it has several components. The first one which is the plates, then we have the rubber case, which is the outer part, rubber case, which you can see here. This one, this rubber case representing the outer part of that battery itself. Okay. And we have the blades inside it. We have plate you can see this plates. Okay? So each one of these is a cell inside IT, group of plates, as we will see right now. And you'll find here a filler cap because it will let you would like to use it in order to provide or add the electrolyte. The electrolyte here is in the liquid form or the asset in the liquid form. So we need to add the electrolyte using this filler caps. And again, when doing maintenance, we will also need to open this filler cap to add distilled water so that lift your heel links inside it. It will connect these assaults. The wizard Stan, the heavy counts. So the cells here are connected together in different forms, as we will see right now is the electrolyte itself is H2SO4 with water. At 40 per cent of the electrolyte is H2SO4 and the rest is regular distilled water. Each cell contains a group of plates. So each one of these cells, you can see 123456. We have your city cells. Inside it. We have a group of plates. The number depends on the design of the battery itself. Now if you look at that Plate itself, you can see is a place here. In each cell consisting of both plates. Negative plates boast of negative, bolts of negative. So we have boast of negative plates. Between them. There is a separator that provides insulation between these two plates. So we have both stiff than installation. The negative then insulation is impulsive insulation. Negative answer. So each cell consisting of a group of plates. Now let sound or stand, how do we connect the Z salts or how can we form a battery voltage here? Now in lead acid batteries are cells are connected in series to increase the voltage of the battery. So each cell, you will find that each cell, each cell is approximately two volt. So when I connect the cells in series, I will increase the total voltage. So e.g. if you look here you can see 1234566 assaults six cells multiplied by two volt, which is the value of each cell it will give us the world volt. So this one is a 12-volt battery. And you will see that each cell has its own filler cap. You can see 123456. So six filler caps, each one for each sub was in each cell we have plates. So we said that cells are connected in series to increase the total voltage. Inside the cell, we have growth of both positive and negative plates. Now, this are arranged in alternating pattern and separated by a insulating separate rooms, as I just said. The blade so as in, within each cell, are connected in parallel to increase the capacity of the Sun. So these plates are connected in parcels up all stiff connected with positive, connected with positive, negative connected those negative. This will increase the total current, the total capacity or impair our of the battery. The battery here consisting of two parts. First, as opposed to negative plates. These plates are connected in parallel, all stuck together, negative together. Why? In order to increase them there are of the battery itself. Then we have the cells. Each cell is equivalent to two volt. So by connecting them in series, both positive and negative, negative bolster post of negative similar to what we did in batteries. This will lead to increase the total voltage of the battery. So as you can see here, Let's firstly leads us. So as you can see here in this figure, this one representing one cell. You can see here negative plate, poles, the plate negative, positive, negative, positive and so on. You can see negative all connected together. Both are connected together. So this is a place within each cell, are connected in parallel. All the terminals are connected to each other. You can see a poster plates are connected to the negative plates of the adjacent cell to form a series connection between cells. So what I mean by this, here, this is one cell, okay? So all of the negative all connected together and all boastful, knitted together to and parallel to increase the capacity of the cell. Now, this is one cell which have one positive and one negative. They're presenting one cell here. Then it gets to the cell. We will take this positive and connected with the adjacent negative of Xanax. Okay? Then this negative will connect it to that, post them and so on. Why to form a series connection between cells. So it's a bolster place of each other which are the sport. All of the poster place are connected to the negative place of the adjacent cell. Two forms, a series connection between cells, I hope it's clear. Now, each cell gives a two volt. So four at 24 volt, or you will need to well vessels. Now let's go to another type, which is the AGM or the absorbed big classmates. So as you can see, if you look at this battery AGM deep cycle, the cycle used in that solar energy systems. Now what do we have seen right now is that this one does not have any filler caps. If you look back here, you will see filler caps to add distilled water or as the electrolyte material. However here you will, or the electrolyte liquid, however, he will find no filler caps. Why? Because this type does not require any maintenance. The AGM or sealed. That's why they are called sealed. They are completely sealed inside a leak proof enclosure that electrolyte inside it is in a non liquid form, so that flooded lead acid batteries have our acid in a liquid form. Here we don't have in a liquid form, Acid itself or the electrolyte itself is inside and absorb glass meat, which is between lead calcium plates. So the electrolyte itself is a stored inside absorbed bit of classmate. That's why it's called absorbed big glass made battery. Now, this is the most cost effective type of Zavala regulated lead acid batteries and has become very popular over recent years. Most of the glass AGM or is absorbed by a classmate have a life expectancy of two to five years. And for higher-quality gel batteries, it is 5-10 years. Now, as you can see here is the life expectancy of this type of batteries is lower than EG as lower than the flooded and Joel batteries. You can see this life is quite low but flooded and laser cutters. So let's talk. So flooded have I has has a higher lifetime Zan AGM. However, the flooded requires maintenance, which we will talk about in the next lesson. We'll see how can we do some maintenance for the flooded batteries. So they require maintenance. And easily m does not require any maintenance, but they have lower lifetime and they have a higher cost than flooded. Batteries are similar to each DMZ don't require any maintenance. They have higher lifetime, but their cost is higher than Asia. Okay, so you can see the advantages and disadvantages of each type is a cost, maintenance and lifetime. This will lead us to the batteries and also type of Zavala regulated lead acid batteries. Batteries are sealed inside a leak proof inclusion was agile electrolytes. So the example here, or the electrolyte material is in the form of job. Unlike that absorbed classmate or the EGM, which was stored inside and absorb whatever glass, meat and ofcourse, unlike Zan, flooded lead as lead acid batteries, which was in the liquid form. Batteries, have been known to prefer my very well under high discharge rate and the last longer than Asia. So they don't require any maintenance. They have higher lifetimes and Asia, but their cost is more sponsor or higher than Asia. They are typically more expensive. So we have the flooded, cheapest option, but requires maintenance. We have the gel batteries. Large lifetime. Don't require any maintenance, but it's the most expensive price that EGM is between them provide no maintenance and but at the same time, moderate cost and at the same time gives lower lifetimes and Joel batteries and the flooded. So you can see each one has its own advantages. This will lead us to another type, which is that lead cadmium batteries too. You'll find usually in PV systems are flooded, that flooded batteries. You will find the ECM, you will find the batteries and the force islet carbon. Also some BV systems use let calm, but they are not popular as the previous types. The late cap on batteries or advanced it. While the regulated lead acid batteries that use a common lead positive plate and carbon negative plate. So ZAP, let's see here which is a positive and negative plates as opposed to one is made of lead and the negative one is made of carbon. Here's a carbon acts as a sort of a super capacitor which allows fast charging and discharging. In addition to prolong get life at a partial state of a charge. Much like sagittal sealed, the is lit carbon are also sealed and similar to the AGM. And z are in similar to as late carbon, similar to sell batteries. They use a gel electrolyte to improve safety and has low maintenance. This type of buzzers can give 3,500 cycles at 50 per cent it is a charge. So if we use that episode discharge of a 50 per cent, we will get 3,500 cycles. Combine the two, the EGM, which can give us 1,200 cycles at a 50 per cent surcharge. So it can last about three times EGM. But however, you have to understand that these values can change from 11 manufacturer to another. There is no one constant value. It can change from one to another. Here I'm converting it to manufacturers with the same pipe and bear our n z have the same as the same ampere hour and same voltage. Now e.g. at an 80% discharge rate, you will get very low amount of cycles, corresponding to 1,000 cycles. Now, zealot carbon, since we talked about lead carbon, this one has a higher cost than EGM, of course, Angela batteries. However, lead carbon compared to lithium batteries has lower cost. So lithium batteries are the most expensive option. So let carbon provides a good amount of cycles. And but however, and so, and of course, a lower cost than lithium. The last one which we will talk about in this lesson is called the tubular gel obese at V lead acid batteries. So you can see here are busy that v.events, lead acid batteries. This one is a tubular. You can see the R and the form of tubes. They are vertically, not horizontally like this. You can see this one. Let's look at another one. This one, you can see it takes space horizontally over this one is installed vertically, as you can see here. It takes is based vertical. And instead of taking space horizontally, which is very, very good advantage. Now these are often referred to as obese at v, which is German, German abbreviation, which is what you can see here, which is equivalent to a stationary Kubler. Play it closed batteries that you blow Jill batteries can offer very high cycle life up to 55000 cycles. But at what depth of discharge? Just 20% depth of discharge and that 40% there. So discharge, it gives us 3,000 cycles if that specific charging parameters are met and the battery is maintained within that correct. A temperature range 15-30 c degree. So as you can see here, this is almost all types. You can see there are many, many types of lead acid batteries. You can choose between them. This depends on that money, you have, that amount of cycles they can give the depths of this charge and many, many different branches. So just to give you an overview about these types so you can already know about them. So when someone told me about was that let carbon or the tubular cell or Zach gel batteries, AGM, you already know about them and you understand now the difference between them. 33. Maintenance of Flooded Lead Acid Batteries: Okay. So let's talk about what Zack, maintenance or flooded lead acid batteries. This type of batteries are, as we said before, is the most commonly used or because they are very, very cheap. And z are the oldest technology. So let's talk about the maintenance of this type of patterns that lead acid batteries, they require regular maintenance, unlike Zavala regulated lead acid batteries, such as the azole, easy M, and other times. So they require regular maintenance to function, probably. Some of the maintenance tasks because that should be performing for the lead acid batteries, include number one, we need to keep our batteries from open flames, from sparks. We need to keep this vent gaps or the filler caps in place. We need to charge it in a well ventilated area because this this type of batteries provide gases, if you remember before. And we need to follow that, but recharge on manufacturer's instructions to avoid overheating of the battery itself or overcharging and onward charging. The battery manufacturer. Here we are talking about the different voltages, floating voltage or the fluid voltage, absorption voltage as the maximum charging can't. All of these specs are found in the datasheet of that battery itself, which we'll talk about in another lesson. Now we need to refill those are flooded lead acid batteries with distilled water. We add distilled water every two to four weeks as needed. Now is a flooded acid batteries. Why do we need to add distilled water and not regular water? We need to add distilled water. Because these pipe of water, the regular water contains a particle which you will harm our batteries. So you need to add distilled water. No, any regular water. Because you will find that the flooded lead acid batteries lose water during that Charles cycle. So you need to add water every a couple of weeks as neat and understand now what are we going to do? So if you look at here, you can see inside it, inside each of these Kab 123456, we have 123456, so each one corresponding to one cell, we need to open each of these filler caps and add that distilled water. Okay. Now if you look at here you can see each folder CAB is corresponding to one, so they must be afield, be filled, refilled regularly with distilled water, function probably and stay healthy and increase the lifetime of these. But now you can see we have distilled water and we add it to each filler cap. Now what are the steps of refilling this address? Number one, we need to fully charged our battery. So in our batteries are fully charged it we check the water level, so we don't do check the water level unless the batteries are fully charged. So winds up it's fully charged. We will start opening each for large cap and check the ward level. Then we will open the event well to check the water level. Then we will start adding water to zoster below the maximum water level line. We don't overfill past is this line. This line depends on what? Depends on the manufacturer. Each manufacturer will tell you what are you going to do or how much you should fill this type of patterns. Now why shouldn't we exceed or reach the maximum water level line? Because you will find that during charging process, that density of the electrolyte solution will start increasing. So if too much water was added before charging, that electrolyte will expand. Electrolyte solution will expand because the battery to overflow and damage it. Also excessive watering can result in additional dilution of that electrolyte, resulting to a reduced battery performance. Remember we said that our solution itself is forming of the electrolyte as warm it off distilled water. And it's to solve for. And each store so far is about 40 per cent. So if we add too much water, this percentage of the H2SO4 will be reduced and it will lay two decaying in the performance of the battery. The battery installation manual would indicate where to find this maximum water level line. Now, after filling our battery with water, we need to check the health of our battery. So how can we check the health of our lettering using the hydro meter? This Nice device here or some nice small equipment. You can see here. Or the nice, not equivalent and multi-device very small tool. This nice tool will help you understand or obtain the state of a charge of your own battery. And you'll also be able to obtain how much our battery or the health of our battery. A hydrometer is a tool used to measure the specific gravity of the electrolyte and a flooded lead acid battery. And it will help us to determine the state of charge of the battery. So that's the specific gravity of the electrolyte will give us is that corresponding state of charge of the battery. And from which we can know if our batteries in a good situation or it needs replacement. You would use as 100 meter, again to check that specific gravity of each cell and ensures that it is within the recommended range. So each a solid, you are going to use this tool for x. So if you look at this figure, we opens a filler cap. After filling that water level. Below the maximum level, then we are going to have this rubber pups. So by pressing this rubber ball, we will soak some of these electrolyte. And we will be able to know the specific gravity of the electrolyte itself. So this will show you exactly what is that electrolyte level. You can see 1.21, 0.4, and so on. Now, by obtaining, so by taking some of the electrolyte using this rubber pulp, we will know what is the value of the state of charge or what is the value of the specific gravity. So why knowing the specific gravity, we will be able to get a state of a charge. So if you find as a specific gravity, Let's delete all of this. If you find that specific gravity is in this range between 1.255 and this range, this value. It means that the battery is 100%, charge it. If it is in this range, it will be 75, and so on. Now someone will ask me, what, what is the benefit of doing this? Why do I do this process and use the hydrometer? Remember that we said when we do the maintenance of the flooded lead acid battery, we are completely charging it at 100%, right? At 100%. And after adding distilled water, it should be 100% completely charged. However, you will find that if you use this tool and you'll find that specific gravity is equivalent to 100%. It means that the battery is in a good situation and it is completely healthy. However, if you are already charged with your battery is 100%, but the specific gravity gives you e.g. this range or equivalent to 75%. What does this mean? It means that the House of the battery is now dropped. The capacity of the battery is not now 100 per cent, but it is now only 75 per cent. So when's our charge controller charges the battery completely up to 100 per cent. It is not actually 100%, it is only 75 per cent. So the embed, our, if it is 100 and bear hour, it will not be 100 and bear hour, it will be actually charged it only 75 ampere out. That's why is the hydrometer is really important to tell you the health of your own battery. So if you find that the battery itself is 75 ampere hour instead of 100, it means now is that battery will provide lower amount of energy. So it needs to be replaced unless your own load is now lower than before. As then we will go to the Amazon stage in that maintenance, which is called the equalization it charged or the equalization process sale. You all see this curve here. We have the bulk, sorption and float. Now the three stages you see here, which are representing the charging of lead acid batteries or lithium ion batteries. These stages will be explained in the lesson of that charging psych. Now, what is important for us is that the equalization process has a voltage, applied voltage greater than the absorption for just remember this information. So what is a function of the equalization? So the equalization is a process that we do as a maintenance for the battery blades. So in order to D sulfate is a battery place of a lead acid battery by carrying out a controlled or what a charge. Now what I mean by this, we apply ten per cent higher voltage than the recommended a Charles Watts or inside that exact catalog itself for that. Or is datasheet or the specs of the battery, e.g. it tells you to charge it absorption voltage at 14 point 1 v as an example, then you will add an additional 10%. This function is inside as are charged to control lights off. So we add an additional percentage this voltage for a specific time, depending on the manufacturer itself. And this will help in this whole fading that battery place of the lead acid batteries. So what I mean by this whole patient wins, this battery operates for some period. You will find that there are some crystals, lead sulfate crystals, which are accumulated on the plates of this battery. So again, lead sulfate crystals, which are accumulated on the plates of this battery. This accumulation of these crystals will lead to decreasing is a lifetime and decreasing the performance of this battery. Now, this happens only in what? Flooded lead acid batteries. Okay? So we don't apply the equalization to that sealed the lead acid batteries such as ECM or gel or any other type. And we don't apply the equalization to lithium batteries. This only done for the flooded lead acid batteries, okay? This is the only one which we do this by applying at them present a higher voltage than the recommended charge voltage. To preform an equalization in charge, you would first apply a fully saturated at Charles to the battery. Then we will compare specific gravity readings of the individual cells using a hydrometer. So how do I know if I need to do equalization or not? So I use the hydro meter and measure the specific gravity of the force. And seconds. For spheres and say, and 61. All of these are used as a hydrometer. Then by getting the readings of each of these salts. If I find that specific gravity difference between them is 0.03 or more, it means our battery requires equalization. Okay. So the experts recommend equalizing one sounds too once or twice a year. Okay. Is this range. So how do I know exactly by using the hydrometer and measuring there? By using the hydrometer and measuring the specific gravity of each cell. And of course, it is really important to follow the manufacturer's recommendation for equalization frequency. How long should the eye or once a month or twice a month. Twice a month or whatever to every two months, every three months. So this frequency depends on the manufacturer's recommendation. And sometimes the duration. How long should I apply? Is this 10% higher voltage for how long? This will be? The bending or the duration depends on the manufacturer itself. Why? To avoid damaging the battery. So again, that data sheet, or this begs the specs of the battery, are really important for the maintenance of battery and for the charge controller and follows the inverse. So in this lesson, we talked about the lead acid batteries or the flooded lead acid batteries maintenance. 34. Lithium Batteries: Hi, and welcome everyone. In the previous lesson we talked about with the lead acid batteries. Now in this lesson we will talk about another one which is widely used in PV systems, similar to lead acid batteries, which is the lithium batteries. So first type, which is a lithium ion batteries. As molarity of electric vehicles start to rise, this lead to falls that electric vehicle manufacturers realized that lease your mind's potential as an energy storage solution. E.g. in the Tesla cars or BYD cows, all of these are using the lithium ion batteries because it has a very large storage capability. So they quickly became one of the most widely used solar battery banks. So similar to lead acid batteries, which is commonly used for a very long time, lithium ion is now widely used. Now why is this? Because lithium ion gives us large depth of discharge, large amount of cycles, which means it has a very large lifetime. As you can see here, lithium batteries, e.g. this depends on the manufacturer, as we said before, it can give up to 10,000 cycles with a depth of discharge 80%. So it gives 10,000 cycles and episodes chars 80 per cent. Now, if you compare this to e.g. the lead acid batteries, it has a 50 per cent depths of the sea charge and they can give 500-1500 cycles if we are talking about the lead acid batteries. So you can see a very small amount of cycles convert it to this. And also the depth of this charge, 50% compared to 80 per cent. Now, you will find that when we are designing our PV system, you will find that depth of discharge is pretty, pretty important when designing or sizing our batteries in the BW system. Now as estimated lifespan of this type of batteries can last 10-15 years. As our types, it can reach even 20 years. Now, what does the lithium ion content? You will find that it has a family inside it are variety of cathode materials. There are lithium ions, which are lithium, cobalt oxide, lithium manganese oxide, lithium nickel, manganese, cobalt oxide. You can see how complex is this, lithium ion batteries. So there are many, many types under it. So when we are talking about lithium ion, we are talking about these different types. Now, what are the companies that are manufacturing or producing these type of batteries? That tastes like company, Franklin, in-phase, solar age, generic, and LG. Now e.g. if you look for a lithium ion battery, is this is an example of one of the battery is not necessarily that all observatories have the same price. But as an example, 110 ampere hour. Well volt battery can cost around 1,300. Now, if you get back to the lead acid batteries are flooded. Lead acid battery, you'll find it was around $130, if I remember correctly, something like this. And the batteries was about 300. So you can see the difference in cost between them. Lithium ion 1,300, flooded 100.300. So you can see there is a big difference in price. Now why is there is a big difference due to the high number of cycles and very large depth of discharge. So if your budget allows you to Bali lithium ions, then of course, golf or lithium ions. If you have a limited budget, then you would go for lead acid batteries or such as the ECM or agile batteries if you don't like to have any concern with maintenance. If you are okay with maintenance, then you will go for the cheapest option, which is a flooded lead acid batteries. Now what are the advantages of using the lacy online buttress? The lithium ion does not require any maintenance or almost no regular maintenance. You can see it is completely sealed, similar to the AGM. As agile batteries, of course, in addition to them that led carbon. The second part is that Z have higher battery energy density. It means that they can hold more energy in a smaller space. And of course, they have higher volumetric energy density, if you remember before, or volumetric energy. If you remember for that we talked about with a graph that we talked about specific energy density and volumetric density at something like this. If I remember correctly, what our per liter and what our bare kilogram. And if you remember from that graph, you can go back to this lesson. If you remember that we said that the lithium ion batteries have the highest what our bare liter, which means it has a smallest volume and has the highest what? Our beer kilogram, which means it is a smallest weight, converted to the lead acid batteries, which you require the large volume and large weight. Now, lithium ion batteries have a longer life cycle and the most have a guaranteed warranty of at least ten years. So if you remember that lead acid batteries, e.g. Joel batteries, AGM flooded. All of these have a range of 3-7 years maximum. However, this one has a guaranteed warranty, at least ten years. Now is a longer lifespan has to do with lithium ion having a higher depths of this charge, as we said before. Now as we said before that the recommended discharge rate or depth of discharge is 80 per cent. Now, there are some types of the newest technology of lithium batteries can even reach up to hundred percent depth of discharge. So it depends on their batteries itself. The end, it's equality. Okay, So it depends on the manufacturer itself. So high on depth of discharge means you can use more of the energy from the battery before it requires to be charged. The lithium ion are best for residential solar installation because they can hold more power in a limited space due to that specific energy density that we talked about before. And it allows you to use more energy, which is great for powering at home. Again, as you will see now, is that a disadvantage of it? Is that it has the problem of hi cost. And then as other disadvantages that we will talk about right now, another thing about it is very efficient, minus five per cent and other can reach 98% and higher. It depends, again on the manufacturer data sheet or the specs of the battery. Now also it is a much lighter weight, only 40 kilogram, e.g. for most three to 3.55 kilowatt hour modules. Now, what is the problems? What are the problems or what are the disadvantages of using the lithium ion batteries? One of the biggest disadvantages is that they are more expensive than other energy storage technology. You can see $1,700 compared to 130 or 200, or 300 or even 400. So the biggest advantage is that they require more money. The lithium ion storage have a higher chance of catching fire due to a phenomenon which occurs inside it called the thermal runaway. This is one of the biggest disadvantages of the lithium ion Z are really dangerous. That's why it is not recommended to have lithium ion in your own home. And you will see what are we going to do about this in the next two slides. So what is the thermal runaway is this is a phenomenon that occurs in the lithium ion batteries when the temperature of that battery increases to a point where it triggers a self sustaining and uncontrollable exothermic reaction. So what, why does this even happens? This happens when the battery is overcharging, short-circuited, or physically damaged. So it's very sensitive to any surrounding temperatures or any problems. It will lead to the thermal arena or runaway phenomenon or leads to damaging of this battery or explosion to be more specific of this battery. So the problem is that this exothermic reaction, so that temperature, so as you can see here, for the thermal runaway, occurs in lithium ion batteries when the temperature increases to the point where it leads it to uncontrollable exothermic reaction. Now, this excess temperature is due to these problems. Okay? Now, what will happen when the reaction occurs? This exothermic reaction generates heat, which will lead to temperature of the battery to rise. Fossa flowers are leading to a chain reaction that will result in battery catching fire or even exploding. Now also the metal oxides in the lithium ion batteries have that dangerous potential to leach out into the environment, which can cause severe health issues for anyone living nearby. Also, the inverse or must be compatible with the lithium ion. So the older inverters may not be compatible with the new modules. Because Alicia minds. Now in order to understand how dangerous is lithium ion, Let's just use, Let's see this video here. Okay? Like here. Okay, so let's close the scanner. Let's go here. You can see this phenomena. Here is where I'm buying a phone with a mobile phone with lithium ion. As you can see, here is another phenomena here. This explosion, which you see is due to lithium ions. You can see because this is really, really dangerous. Here we can see this explosion inside the house do to also the lithium ion. So I can tell you, here's an electric scooter which uses a lithium ion. Here. Again, another fire is this one is a file due to lease your mind. So you can see how how dangerous is lithium ion batteries. Are we going to do about this? How are we going to go to lead acid batteries? Go to other options or what we can do. Now, luckily, zeros are an alternative to lithium ions. The alternative is using one type of lithium ions called the lithium iron phosphate batteries. Lithium ion phosphate batteries, they are safe and don't have the problem of the thermal runaway. Or you will see on the battery itself, you can see a live PO4, which is lithium ion ion. Before, which is that phosphate ion here uses the lithium ion phosphate as the cathode material inside this battery. Now, this one has a lifecycle of two to four times longer than lithium ion. Because the lithium ion phosphate is more stable at higher temperature temperatures. The lithium ion phosphate can also be stored for longer periods without with degrading. As a longer life cycle hubs in the solar installation, where the installation is costly and replacing batteries disrupted the entire electrical system of the building. So we'd like to, if you are installing it inside a building and you would like to have an option with along the life cycle, then you will go with lithium ion phosphate batteries. They are safe and don't require a change in during the lifetime of it. They are also inside it. There is no toxic materials are like lithium ion batteries, which we talked about proteins or previous slide. And we said that lithium ion batteries contain metal oxides, which is harmful to the environment, and also have a severe health issues or causes severe health issues. They are easily recyclable and even able to be repo, repo posed as a new batteries. Lithium ion batteries, or the lithium ion phosphate batteries contain phosphate salts instead of the metal oxide phosphate salts and instead of metal oxides, which makes it a lower risk of environmental contamination. The lithium ion batteries also are non-combustible, making them more stable and safer than lithium ion, which means that you don't suffer from thermal runaway phenomenon. However, the disadvantage of using this butter is that they have a lower energy densities and lithium ion, which means they require more space, or they have a higher volume or higher weight than lithium batteries. They store less energy per unit of weight or volume. They are also less suitable for applications where space and weight are at a premium. So when space and the weight is limited in allocation, then we cannot use this type of buttress. We will need to find the lithium ion again. That's why is that lithium ion phosphate batteries must be larger than lithium ion to hold the same amount of energy. Now as you can see here, this is a graph for lithium batteries. I don't remember exactly if it is a lithium ion or lithium ion phosphate or lithium battery. So in general, this lithium batteries are having a lifetime or lifecycles are close to each other. So as you can see here, one of the types of lithium batteries, you can see that at 40, 40 discharge rate of discharge, you can see how much it can give. I can give more than 10,000 cycles. Combine the two, e.g. the EGM absorbed big gloss, matte, or the pasture is horizontal flooded late as buses, which can give between 1,000 or 1,500 for the good batteries. So you can see there's a very large difference between them. Now we have to mention something which is really important is that as this graph, again, can it change from one battery to another? So we have to look at that data sheet or suspects of the battery to understand how, how many cycles does this battery will get. Okay? So in this lesson, we talked about with the lithium batteries, lithium ion, lithium ion phosphate batteries. 35. Nickel Batteries: Hi, and welcome everyone. In this lesson, we will talk about that nickel batteries. So we have several types of nickel batteries. We are going to talk about two types in this lesson, that nickel cadmium batteries. Nickel cadmium batteries aren't widely used as lead asset or lithium ion batteries. They are less used in BV systems. They are favorite or between or amongst the aircraft industry. E.g. is a top manufacturers of nickel cadmium batteries are horses and SAFT. Now, e.g. if you look at the graph for one of the types of nickel cadmium batteries, you can see at a 50 per cent depth of discharge, it can give a resolves on cycles. And if you go down to 20%, you will get my installs and cycle which is higher than that, are flooded or AGM or gel batteries. So Gibbs good amount of cycles compared to these buttress. Now what are the advantages of using the nickel cadmium batteries? So z are durable, they can operate at extreme temperatures. Additionally, Z don't require complex battery management systems, and z are maintenance free. Nickel cadmium batteries are all popular for larger scale applications, e.g. in the utility solar energy storage because of their durability. Now what are the disadvantages of the nickel cadmium batteries, which is pretty, pretty important. That's why we shouldn't use it at home. Number one, cadmium is extremely toxic. In fact, the use of cadmium is banned in, even in some countries. This makes them hard to dispose off or get rid of it. They suffer from a phenomena which I have talked before and mentioned before, which is the memory effect, which is also known as the battery effect or lazy battery effect, or the battery memory. So what does that leaves the butterfly effect or the memory effect? Now this effect observed in some batteries, e.g. it is a nickel cadmium batteries. Nickel cadmium rechargeable batteries that can be recharged it similar to lead acid batteries. However, the memory effect is clearly observe it in size these batteries, nickel cadmium batteries. Now, this phenomenon causes them to hold less HR. Now what I mean by this, it describes a situation in which the nickel cadmium batteries gradually lose their maximum energy capacity if they are ribbit, ribbit literally recharging after being only partially this chart. You will find that the battery appears to remember is that smaller capacity? So when you do this several times, it will remember the last or the smaller capacity. What I mean by this, if you look at this figure here. So we have here our battery, nickel cadmium battery. So you can see that this one is 100 per cent the whole battery. Now, let's say I frequently, frequently they exhaust 50 per cent of the battery. Okay. So let's say this is our 1,000 ampere hour. And every time I take 50 per cent, it drops it down to 500 and bear our right. So if I do this several times, you will find that the battery will have some memory effect. It now will sink is at its own capacity now is only 500 ampere hour, not one seltzer. Why? Because you keep taking only 50 per cent. Let's understand this enormous our way. So let's say it's this part or this part which I have used is this whole battery is I 1,000 ampere hour. Now, let's say you only used, let's say 600. And then when I reach within a window, reaches this part, which is 400 and per hour. At this point, we start charging again, then discharging to 400 ampere hours. Any charging, again, this is a charge. If you do this several times, the battery will think that it's red capacity is this part only which is a 600 and per hour. So now my own battery, its capacity to reduce the from 1,000 ampere hour to 600 and bear out. So how can I solve this problem? This problem can be eliminated by repeated fall DC charge. You take thousand ampere hour and discharge it completely to zero, then charge it completely, then does the charge is completed, and so on. Now we have to remember if we do this. If we do this here, you will find if we use e.g. 100 per cent depths of despair charge, we can say that the number of cycles which can be taken will be very, very small because we need to display this histology to 100 per cent. That's why this is not a good thing, but with nickel cadmium batteries. Now, this will lead us to another type of batteries, which is the nickel iron batteries. So for this pipe, iron, Edison, which is a major manufacturer of the nickel ion batteries, estimates that their batteries will last ten years with proper maintenance, you do a frequent maintenance for this type of batteries. It can last 30 years. Was that without replacement? This Bible, but this can give you 11,000 cycles at 80 per cent depth of discharge. So you can see how much energy you can take, or how many cycles can you take from this type of batteries? And that is a good thing about nickel ion batteries that Z or shiver also then lithium ion batteries, e.g. 100 and bear, our 12-volt battery can cost around $1,100. Combine the two, if you remember in the previous lesson we talked is that lithium ion was around 1300s. So this one is sheep or Zan, lithium ion and you can give more cycles that once I wasn't surrounded, was at 10,000 cycles. This one is 11,000 cycles. So we talked in this lesson, I've always a nickel cadmium nickel ion batteries. 36. Flow Batteries: Hi, and welcome everyone. In this lesson, we will talk about another type of battery scalds or flow batteries. So this type of batteries are an emerging technology in the energy storage is sector. They contain an electrolyte liquid that flows between two separate champions or tanks. You can see we have one tank and another thing between them, electrolyte liquid. So we have here palms is that bushes this that makes us this electrolyte liquid flows between two separate jumps. Now since you have two separate chambers and pumps, it means that the size of this battery is very large. You can see this is a size of a flow battery. It has a larger size. Now, this butters are now beginning to rise in popularity. However, the only problem is that the larger size makes them more expensive than other types of buttress. Now with a high price combined with the larger side, makes it hard to adapt them to use. What are the advantages of using this type of batteries? But one, they have 100% depth of discharge. It means you can use all of the energy stored in the battery without even damaging that battery. Also will find that the liquid inside diameter is a fire retardant. So you don't have to be worried about the thermal runaway similar to the lithium ion batteries. Flow batteries have the longest life span of silty years. So you can see it longer than even the lithium ion batteries. They require low maintenance. And this one is used for a very, very large scale installation. So they used in very large or utility scale. Bv systems are not used in home installations. They are used in the utility scale and installations. They also can be or remain discharged indefinitely without any damage. So this was a small introduction about user flow batteries. They are not common as lead acid batteries and lithium ion, but we need to talk about them so you can have an idea about them and their existence in the BV systems. 37. Cost of Batteries: Now let's talk about with the cost of batteries. So let's have a comparison between several types of batteries, and let's understand which one should I use. So this is a forest comparison which you see here. We have the total cost of a life comparison. You see that we have a flooded lead acid battery and AGM battery, which is absorb it, and gloss matte batteries, or a mat, which is abbreviation for material. We have agile battery. We have a lithium ion battery. Now let's look at the cost. The cost of the flooded lead acid battery for this system is $185, 270, 400. Alicia wine, one substance you can see it has less flooded lead acid battery, or the cheapest option, unless you're mine, is almost six to seven times the flooded lead acid batteries, then you will see that Joel is higher than ECM in price and EGM is holidays then flooded lead acid battery. This is Forest Street solar street light project. Solar street light project. You will find the hidden installation cost. Then we have the maintenance. So we said lithium ion does not require any maintenance. Jobs require very small EGM, very small. Flooded requires regular maintenance. We said we need to add to the equalization process, we need to make sure of is that level of the electrolyte and so on. Now this represent things are charging costs for each one and replacement cost. And how many replacement and how many cycles. So you can see flooded lead acid battery. One of them is the batteries which are used is having 500 cycles. That EGM has a 400 cycles lower than flooded lead acid batteries. As we said before gently here is 1,000 cycles. Lithium ion is 7,000 sites. So we are building our system based on the 7,000 cycles. So you can see since it is giving 70,000 cycles, we don't have any replacement for lithium ion converted to juggle, which we have 1,000 cycles. So we were blessed them seven times. This one replace the 20 times. This one is replace the 14 times. So as the lowest one is lithium with zero and the replacement. Then we have that Joel batteries, then the flooded lead acid batteries, then AGM. This is that replacement labor cost. And the total cost of a life, including the replacement cost, which you see here. As you can see here. Now, in the end, you will find that the total cost over the life of the 7,000 cycles, lithium ion has the lowest cost, then is agile batteries then flooded lead acid batteries and Asia. You have to remember that this is not always the case. This is the vendors on how many years does the system will remain, e.g. this one is 7,000 cycles. So it will remain for a long time. Let's say e.g. at 20 years. For a long time, 20 years, Lisa mine is the best. However, they have a high initial cost converted to a flooded lead acid battery and the AGM or gel. Now I would like to say something here is that this is a cost of just one battery. Now, imagine that you have e.g. ten batteries or 20 batteries. Difference in cost will appear more. Now, as you can see here, this is another comparison with, however, this comparison is for ten years for a small time. Now if you look at this comparison here, you will find that the total cost. So we have for the crown flooded lead acid battery sealed here like AGM or gel and lithium. Now here's the system installation and this is a battery cost. You can see flooded lit asset 2000 800,900 and leaves him about four to five times the cost. However, if you look at the battery cost injustice ten years, here we are talking about a smaller period, not 20 years but only ten years. You will find that here we have 21,024.26. So in this case, the flooded lead acid battery is the cheapest option. Why? Because it is, we are comparing with very small number of years. So as you can see here, 1,200 cycles, 1,000 cycles and unlimited. This is theoretically are limited. This is at 10,000 cycles, e.g. unlimited for that period of ten years. However, if you extend this ability to 20 years, as the lithium ion will win a shorter number of years, it will lead to flooded lead acid batteries and sealed becomes a cheapest option compared to lithium for a longer period of time, is Alicia will win. Okay? So I hope Zach cost here ****, but you understand more about the difference between these batteries. 38. Battery Balancer: Hi and welcome everyone. In this video we'll talk about what an important device which is optional in BV system. You don't need to have it, but it will help extend the life of your own batteries, which is the battery balancer. So what does the battery patents are? So as you can see, this is a device which was, there are many companies which makes this the wise. One of them is vector on energy, which is also manufacturing different charge controllers. The battery balance equalizes the state of a charge of 22 volt batteries in series or multiplet batteries in series. So the battery plants and can be used in conjunction with a solar charger control. So we have a charge controller that shows us our battery in parallel to it. We can also use this but to rebalance. The solar charge control regulates the flow of electricity. As we said before, eclipses are charging of buttressed by controlling the voltage, winds up but repellents or equalizes the state of the charge of the batteries to ensure that they are on the same level. So what I mean by this, if we have two batteries that I would like to show. So each one of these devices, each one will be used for two batteries. So the number of battery balance are required. It will be number of batteries minus one. Okay? Remember this number of battery balancers, if you are going to use it in your own PV system, number of pottery balance of z will be equal to number of batteries minus one. So if we have two batteries, we will need one battery balancer. If we have three batteries, then we would need to but repellents or if we have four batteries, then we need three battery balancers and so on. So let's talk about one of them. One battery balancer. Here we can see a 12-volt and 12 volt. These two are being recharged using a charge controller. Right? Now, the most important things that you will find is that these two batteries may not be identical to each other. One of them may have a small difference in manufacturing. Not all batteries are similar to each other. Another thing is that one of the buttress may be new and the other one may be old. So both of them. 39. Lead Acid Battery and Lithium-Ion Charging Cycle: Hi and welcome everyone. In this video, we'll talk about the lead acid battery and lithium mine in a charging cycle. This will help you understand how does the lithium ion or a lead acid battery is charged it. And until we understand different voltages inside that data sheet or the aspects of the battery will find in that data sheet folds that battery, you will find that float voltage. You will find absorption voltage. You will find also that bulk voltage. So what does this really mean? We will understand right now. So as you can see here in this figure, this shows you that charging cycle of a lead acid battery and lithium ion batteries, they are similar to each other. So the lead acid batteries here, we will start with it. They are similar to each other, but we will say that we are talking now about the lead acid batteries. They are charged using a constant current, constant the voltage method. And what I mean by this, it means that we start with a constant, was a constant current. And then we start with a constant current. Then we will have a constant voltage. As you can see if you look at this figure, this representing the charge time on the x, on the x-axis. And this is a charging voltage or charging state of the battery. Now as you can see for the current, charging current, you can see we started with a constant, gas constant, let's say five and bear constant value. Then we, in the second stage, we went to a constant voltage message. You can see here, constant the voltage. Okay? Now that's why it's called that constant current, constant voltage starting with a constant current. Then in the next stage, we start with, we continue with that constant voltage. Now with this method, we start charging our lead acid batteries or lithium ion batteries in a three stages. The constant, the current is charged. Constant car can't charge, as you can see, a constant current. Then the second stage, which is the first stage, is known as the Paul cafes or the bulk stage. The second one is called Zach sloping get charged. Second stage is a Tobin and charge or the absorption stage. The final stage here, it's called the float, the charge or the fluid state. So we have bulky phase, absorbed or M phase and the fluid phase, three phases or three stages, 12.3. Now as a first stage during the bulky charged, and this part's a battery is a chocolate at a constant current, as you can see, five and beer is the maximum safe rate, the maximum current. You will find this value inside that datasheet or specs of the battery will find what is the maximum a charge current that I should set inside the charge controller? So it is a maximum, say friends that they will accept until the voltage rises to near 80 to 90% of the fully charged level. We're at assert at each state of the charge. State of charge. We said that there is an equivalent voltage of the battery, right? So when we are having a low state of charge, let's say 50 per cent or 40 per cent. We are in the stage or the ******* is charged state, we provide constant maximum current to increase this voltage from, let's say e.g. or increase the state of Georgia from 30% to a state of a charge of 80 to 90 per cent. So at this level here, this level here you can see is this level here. At this point here, we will have between 82 line to present state of charge, Okay? Now 80 to 90%, full charge level or close to 100%. And this range, we will start the next phase, which is the absorption phase. So again, here in this stage will provide, using the charge controller will provide the maximum current. This will keep increasing or recharges the battery from 30% or 40% or any level up to 80 to 90%. Starting from the 80 to 90%, we will end the poll Qi charging phase and we will go to the second phase, which is the absorption phase. In the absorption phase, that battery itself will be charged at a constant voltage with a constant value, which is known as. Absorption voltage until it is reaching as 100 per cent. So in this stage and this part, we give a certain voltage, let's say 14 point 1 v. This can be taken from where? From the data sheet or the specs of the battery will find it inside it. Inside the absorption phase of that battery. We will provide a constant voltage using a charge controller until it reaches 80-90%, until it reaches the point, which is 100%. When the state of a charge reaches 100%, the battery will be fully charged. Now, this will lead us to the next stage. Okay, but before we go to the next digital, finds that during the absorption stage, which is this here, you will find that the current goes from the maximum value which was inside that pole copays, which is five amperes. And stars, gain width time to reaching a very, very small cat. You can see that charge, it can gradually decreases as the battery becomes more and more charge. Now, the final stage of the reaching 100%, you will find that we will have the floating charge stage lost one, or the float voltage. You can see that here. The battery maintains as this stage and maintains the battery at all. It charges 100% whistleblower constant voltage, known as the float voltage. So we have here three stages. The first one, constant current, which we will find from the datasheet of the battery itself. Second stage, which is absorbed per cent absorption stage, we will provide a very high voltage, higher than the normal voltage called the absorption voltage. How can we find this value from the data sheet? And finally, we will have our float value or the float voltage. This will keep the battery adds 100% stage. Now why is this? Because if you remember that the battery itself have a sulfur DC charge. So in order to prevent the water from going to 100% lower value, we add all that charge control gives us a battery, a certain voltage known as the float voltage. These values all are found in the datasheet of the battery itself. So we will find this in the lesson of that data sheet. So I hope you now understand how we charged lead acid batteries and also this curve. This curve which you see here, is similar to the lithium ion battery. 40. Datasheet of a Solar Battery: Hi and welcome everyone. In this lesson, we will talk about a very important topic inside solar energy. Or to be more specific, insides a solar batteries, which is called the datasheet of the solar batteries. This will help you understand well about solar batteries. Now, let's just start. If we open at datasheets, e.g. for a solar battery and AGM battery with 12 205. What does this mean? We will understand right now. So this is the name of the batteries that I'm using from Frozen company. This battery, which is an AGM poetry, its type is an AGM, as we will see right now. We are going to discuss it in this lesson. So as you can see, we started with, if you look at the specs, you will find the first part, which is the voltage. You can see this is a battery voltage, voltage of the battery, 12 volt. So the voltage taken here is 12-volt. That was the second part is the embedding of our rating or the capacity of that battery itself. And the C rate of the battery. You can see is this battery is at 205 and bear hour. This is the capacity of the battery itself. You can see it's also inside the model name to 105, and the 12 volt is also on that model name itself. Now, what this really, really important is that you will find 205 ampere hour, which is embed our rating at 20 h. What does that when our mean, it is representing the C rate or the discharge rate. So that when t hours here representing C 20. And we talked in our course for solar energy or power c times c 20. And we said that see 20, it means discharged into when t hours. Okay. Now this capacity when it changed is that discharge rate, will it change as we will see in this video, part, which is that type of battery can see evolve regulated lead acid battery or its type is this valve are regulated or the seal, the type battery is an AGM or absorbing glass. Of course, we said before says that sealed battery like EGM does not require any maintenance. Then the last one which is important for us is IEC 614278 plus years life. So what does this represent? This as a standard developed by the International Electrotechnical Commission or the IEC for second results and the batteries for PV systems. Now, you have to understand that these batteries are subjected, all subjected to justice under this standard, which involve is the heavy. This is charging the batteries, which is a typical scenario in solar applications. And we say we are talking about deep cycle batteries. And this does z. We're stressed and z will be operating in abusive testing environment. Now, the years of life mentioned in this data sheet, besides this standard representing that expected life span of the battery wins, they are used in the PV system as the officers according to the standards that we talked about right now. So it's a lifetime of this battery can reach more than eight years. Again, this lifetime depends on many factors such as that depth of discharge. It depends also on that owns that temperature is a storage temperature. It also depends on the operating temperature of the pottery. All of these are factors that affect us alive psych or the cycle life to be more specific. And also seeing here you can find inside Zach datasheet is the physical specifications. You'll find here first, Zelda dimensions of zap battery reaches the lens of the battery is our width and height in millimeters, inches. This number is anxious and this one is in millimeter, as you can see here. Second one is the weight of the battery. How many pounds? 122 pounds or 55 kilogram. Then we have the electrical specifications, which are really important for us, is that you can see voltage and capacity, capacity and energy of that battery. So you can see is the energy of the battery in kilo watt hour. So you can see here at two when t our discharge rates. So when we are discharging our battery into when 2 h, we will get energy equal to 2.46 kilowatt hour. Now, where did we get this value? It is really easy. So we said before that the ampere hour of this battery at a 20 hour rating is 205. If you take 205, which is the ampere hour, and multiply it by the voltage. You will get the energy and bear our multiplied by voltage gives us the energy, which will give us 2.46 kilo watt hour. So this value obtained by multiplying is at 20, our capacity multiplied by voltage of the battery itself. Now, very important part which we discussed before, we said that the discharge rate or that C rating, Satan's it, when is he hundred effect? This is the capacity of the battery itself. So you can see this one is at 20 our SC 2,205 ampere up. Now, as you can see that as the discharge, the time increase, as we talked to before, as discharge time in degree increase, you'll find that the capacity of the battery starts increasing since we are discharging in a longer time. If you decide to discharge it in a short time, let's say 10 h, then you will only get 174 and bear our C will get lower amount of energy. Now, this is really important because if you can, you can charge your battery in a longer time. It is acceptable. However, if you decide to discharge it in a lower time, it will affect its lifetime and you will get lower capacity than the rated value. Now, the next one, which is the charging instructions. This is really important. Why? Because we talked about this before. We talked about that charging cycle of lead acid batteries and lithium ion batteries inside our calls for solar energy. Now, when this values, which you will find in that data sheet itself is really important for, for the charge controller or the settings of that voltage settings of the charge controller. You can see here that charge or voltage settings at the 25 Celsius degrees, the ad that went pumps Celsius degrees. These values will be used for the charge controller and the 25s. So since the key, now, you can see that this battery can be 12 volt or can be connected to form a 24 or six, or 48 as you'd like. Now it was a forest important part which is the maximum charge. This is the maximum current that cans are charger. Charger can give to a battery without any damage. You can see here, a constant under or over charging will damage the battery. Overcharging will damage the batch. So we cannot exceed the maximum charge current satisfied by the manufacturer itself. The maximum storage account is 20% of C 20. So what does this mean? It's the value is 20% of the current at DC charge rate of 20 h. So that battery, if you remember, battery has a capacity of 250 ampere hour Etsy 20, C 20, which is the discharge rate, which is 20 h. Now, I would like to find this equivalent current. So we have 205 ampere hour and we have 20 h. So in order to get the current, we will take 205 ampere hour, divide it by two when t hours. So we will get 10.25 and pairs. This is the current of the discharge current at a rate of 20 h. Now it was a maximum of charge current is 20% of this value. So we will say is that when 2% of C 20, which is 20% of this value, will give us 2.05 and bear. So this is the maximum current that I can charge to my own batteries width. Now the second part, which is the absorption voltage. Now, if we are working at 12 v, absorption voltage will be 14.4 and zap flawed voltage will be at certain 0.5. Now we talked before, upholds up soaps and voltage and flood voltage inside the lesson of the lead acid and lithium ion charging cycle. And if you don't remember, absorption voltage was the voltage after the stage. So we said we have three stages of a charging. The first one, which is the Paul keep charging fees, at which we will add the map, which will supply. The maximum charge or current. Then we have or after reaching 80 to 90% of the capacity of the battery or SOC, or the state of charge of 80 to 90%. Then we will start using this absorption voltage to make the pattern reach hundred per cent. So if you remember, we said that the battery is charged it at this constant voltage, which will lead to decrease of the charging current until it become very small and the battery will reach 100%. And we said that the fluid voltage is used it to keep the battery at the state of a charge of 100%. After a charging, our afters absorption is stage. Now as we said before, that this is important because we have the sulfur discharge of the battery and we need to keep this capacity at 100%. So these values are really, really important. This one, this one, this one. And if you have a 24 v and you are going to use these values. So six, these values 48. And so these values are really important to be added to. The charge controller is the one which will help any charging our buttress. The next one which is a charging temperature compensation. Now what does this even do? You can see that here. That charging temperature compensation, you can see it's 0.005 volt. Bear cell for every 1 c degree below 25 Celsius degree and subtract 0.05 volt per cell for every one socials degree above 25 sociologically. So what does this mean? Now, if you remember that we said a six volt battery consisting of three salts. At 12 0 volt battery consisting of six. Here we are talking about the lead acid batteries, which is in this video. So this results H1 gives a two volt, approximately two volt, giving us six volt. If we have six assaults, then it will give us 12 volt and so on. In the 12 volt battery. Let's say we have a decrease in temperature. So that previous values here, this value is 25 Celsius degree. Okay? And let's say e.g. we are talking about absorption volts 14.4. Remember this? 14.4? So we have 14.4 volt. Okay? Now for each, for every 1 c degree, blue 25 Celsius degree, add 0.05 volt per cell. So it will be plus, plus 0.050, 0.05 multiplied by number of cells. Since we are talking about at 12 volt, then we have six assaults. So we'll multiply by six. And then we multiply by what? By the difference in temperature. So let's say we reach it at ten Celsius degree. Then it will be 25 minus ten Celsius degree. And same for Fahrenheit. You will add this for every 1 f. This will give you the new voltage. Now, if you are going into an increase in temperature, you will make this one and negative sign. Okay, is this little compensation as this will help us in, due to that change in temperature, do as the change in temperature leads to change in that charging voltages, absorption, fluid voltage, and so on. So we need to add this value, this smallest change, as a compensation for the charge controller itself. So the charging temperature compensation is used to adjust the charging voltage of the battery based on the operating temperature. This is important because the optimal charging voltage can vary depending on the temperature, as we have said, for the lead acid batteries, we add a temperature compensation or that soldier to adjust for temperature variation is set to prolong as a bachelor life by up to 50%. So why do we do this? Because it will help extend the lifetime of our battery. This will hold also in preventing overcharging and under charging of the battery to reduce, reduce its performance and lifespan. Now, before we go to the next slide, now you can see here we have also self and this is charge. You can see self discharge. For the cell, for the set charge here, you can see it is less than 3% per month depending on the storage temperature, temperature. So it means that less than three per cent, so that battery will lose 3% of its capacity for each month less than this value. But if you remember, we talked about the sulfur does a charge before. And we said it will change depending on the temperature or the storage temperature. You will find in that data sheet also this curve is that we will see right now in the next two slides. Now as you can see, I'm also seeing here you can see operating temperature. So the operating temperature is between negative four Fahrenheit, 222 Fahrenheit, or between negative 20 Celsius degree and plus 50 sources again. Now, one important thing is that you would want if the temperature is below 32 Fahrenheit or blue zeros as degree, you need to maintain a state of a charge and greater than 60%. State of charge, greater than 60% means we are talking about at depths of this a charge, depth of discharge equal to 40%. So we said before that the lead acid battery recommended this depth of discharge is 50 per cent. However, if the temperature became very low, this will affect the battery. So we cannot charge more than 40%. Okay, So that temperature have a really high effect on the battery itself or the battery performance. Now remember the state of charge here. This is another curve and another table that you will find in that data sheet. Percentage a charged cell and a voltage. You can see at 100%, the voltage will be 12.8 for the open-circuit voltage. And you get an album meter and measure the voltage across this battery, you will find it is 12.84 volt, going down to zero, you will find this 11.64. Now this value is pretty, pretty important to add to the inverter. If our batch reach it. This value is the battery should be disconnected from the inverter to prevent any false or damage to the battery. So it is important to add this to our inverter. This is a critical or the final value to prevent damage to the battery. Battery and reaching zero per cent and you start taking energy from it, it will start or it will be destroyed. You can not take more than this, more than zero per cent of the budget still has some voltage. But if you take more sensors, the battery will be damaged or destroyed. So you have to make sure that you don't exceed zero per cent. And my own suggestion for you is that if you are using lead acid batteries, e.g. we are using 50 per cent depth of discharge. So if there is another source like the grid, e.g. then you can assume 50 per cent state of the charge inside there or depth of discharge. They will be the same inside the invoked on its own. E.g. inside the inverter, I can say if the battery will reach a state of a charge of 50% and the grid is available or the greatest available, then in this case you can disconnect as a patch. If the grid is not available, enter my own loads are critical and important, then the battery, then you can discharge above 50 per cent. Okay, is this is found inside the settings of the inverter itself. Now another curve, this is what we talked about before, the depths of DC charge or DOD, or how much I can take from the battery. So we said before that the depths of the sea charge effect as the lead acid batteries, lithium ion, and any type of batteries. So we said that the depth of discharge for lead acid batteries, EGM is a lead acid battery recommended one is 50 per cent. So at 50 per cent, we can get approximately 1,700. 1750 depends on the battery itself. This one is one curve for the batteries that we are discussing in this lesson. You can see that if you use e.g. decided to use an 80 per cent of the battery, 80 per cent depth of discharge, you'll find that you will take only 1,000 cycles and instead of 1700s. So as the depth of discharge increases, as we learned before, the amount of energy taken from the battery or the lifetime of the battery or number of cycles will start indicating a higher depth of discharge. Use the lower number of cycles that can be taken out of the budget. If you don't know about them, so this is charged or you have forgotten about it. Get back to our lessons. You will find that listen for the cycle life and that dibs on this chart. The next one is a person's capacity versus temperature. You can see here is the available capacity from the battery versus that temperature. You can see is that here, e.g. this is a temperature. So we are operating at what value added 25 sources degree adds this point here. So if you go like this, you will find it is approximately hundred per cent of that battery is available for you. Now, if Zack temperature or the operating temperature starts to decay. If you are operating in that region less than 25 Celsius degree. Then what I'm going to do is I'm going to, let's say e.g. I. Am operating at five Celsius degrees. Okay? Here is the equivalent temperature in Fahrenheit, as you can see here in Celsius degree, if I'm breathing at 15 associate's degree, you will find that the available capacity will be about, let's say, 70%, 70%. So our battery now has two factors, depths of this charge. And we will have a temperature compensation if you are operating at a low temperature. So if you are operating at temperatures less than $0.25 as degree and the going down, you need to look at this curve, which you'll find in that data sheet or the specs of the pottery, it will help you select the correct one. This is one which is called the temperature compensation correction factor. So it is a correction factor. You need to make sure to add this in your own calculations. If that temperature of z location decreased a lot beyond 25 Celsius degree. So you will find that the lower temperature as our lowers ampere hours that can be taken from the battery. Then we have the sulfur discharge curve, which we talked about before. If we have a battery with 100% state of Georgia completely charge it or fully charge it. Then we start storing it for a couple of monsters. Now, you will find that the state of charge will start decaying with time. Decaying, whose time? As you can see here. Now, why is this? Because the battery inside it has its own internal chemical reactions which will lead to self a discharge of this battery. Now, you will find that the sulfur does it charge? It changes depending on the temperature tensile. Yes, 25, 30, 40. So the lower the temperature, the lower the cell for discharge happening to the battery. So as you can see here, at the ten Celsius degree, e.g. for 14 mouses. Look at the three curves here. At, at ten Celsius degree, we are beyond 75 per cent. At, at 25 degree, we are about 50 per cent for the 30 Celsius degree, about 30%. So you can see as the temperature increase that settled for discharge increases. That's why when we store our petrous, we store them in a cold location. This will help us to extend the lifetime of the battery or reduce they'll silver DC charge and size the battery itself. So you can see here's the higher the storage temperature, as you can see, 40 Celsius degree. So let's delete all of this at Ford sells as degree. You can see is that so salt is very, very fast. So the higher the sulfur discharge rate of higher temperature, higher self DC charge. Another thing which you can see is the performance curve. Here. This will give you that amount of amperes and the time. So it gives us that discharge current ends equivalent time similar to the M pair, our figure, if you remember it, is a tuple of the ampere hour. The Seton is a C20 and see hundreds, if you remember it. This curve, if we get back here, here exactly, you can see this curve. Here. I'm bear our hair. Each district charging time, agency charged line has its own corresponding ampere hour, which is corresponding to a certain current. So each discharge time has its own distinct charged current. This can be obtained using this figure. This figure shows the performance of the batteries that includes this, the charge current and hours. Okay? So if you delete all of this, Let's say this is at ten amperes. This, remember this is a logarithmic scale. So here we have a 20 amperes. Or let's look at here 10 h, this one is at 20 h. 20 h. Okay. Similar to the pottery, if you go like this, it will be approximately close to ten amperes. Close to ten amperes. Okay? So in this lesson, we talked about specs and datasheet of the battery. Hope this helped before. I hope this lesson was helpful for you in understanding more about reading Zach datasheet of the batteries. 41. Small Correction in Datasheet: Hey, everyone. In this lesson, we will just give a small correction regarding the datasheet lesson that we talked about in the previous lesson. Where's the mistake exactly. If you remember in the charging instructions for the maximum charge current, maximum charge current, this one. We said that 20% of C 20. What did I think? I thought that 20% 0.2 multiplied by the current of C 20. If you remember from here, we had this value, 205, and we had 20 hours. I took two of 105/20 hours to get two pairs and not two pairs, ten pairs. Approximately ten empires. Then I took this current, which is a current of C 20 and multiply it pi 20%, ten multiplied pi 20%, so it will equal 22 amper. This battery will be two pair, it will accept the maximum charging current of two pair. However, I was thinking that the charger controller itself, it provides current in the range of 40 s or 60 s, depending on the type of the charger controller, another 180 Ms. How does a charger controller providing this large amount of current will charge a small battery that will take only two pairs? So I thought to myself or I searched for the solution. I looked for another data sheet to clear this misconception. The misconception was solved by very easy method. When the data sheet says 20% of C 20, it actually means exactly 20% of C 20. What I mean by this, we will take 20% and multiply it by the rating itself, the empire hour, which is 205. And the result will be the pairs that is accepted by the battery. We don't divide by the number of hours to get mpiirs. No, we just take the mire ho rating and multiply it by 20% to get the correct mpire. 41 s is a very, very practical value and very close to the values of charge controllers like 40 s or 60 s or 80 s. That is the first part. Second part is that where the data sheet exactly that contains this information. I looked for the vectron company. Vectron also has a valve regulated lead acid batteries or lead acid batteries in general, and you will find that in the data sheet itself, you can see here. A charge current, where exactly here, charge current should preferably not exceed 0.2 c. What does this mean? It means that the charge current should not exceed to 20% of the capacity. Here in this data sheet, we're talking a pot a battery of 100 and per hour. So 20% of 100/hour will give us 20 ampers. It means that the hundred empire hour battery has a maximum current of 20 pairs. So if you look at our previous battery of 205, which is double this value. It had 41 pairs. If we took about 20 pairs 400/hour, so that 200 am per hour will have a 40 s. This value is correct. This is a correct solution. That is the first thing. Second thing is that you will find that always or in general, the charging c, charging current for lead acid batteries is in the range of 20 2022, 25%, 20-25%, and you will find this value exactly inside the data sheet. That's all for this lesson. 42. Introduction to Charge Controllers: Hi, and welcome, everyone. In this lesson, we will start talking a it, the charge controllers. What is the function of charge controllers? Charge controllers are used in BV systems or solar energy systems in order to number one, control the current going in and out of the batteries. Number two, protect the batteries from over charging. Number three, it regulates the voltage entering the battery, and number four, it protects the battery from over discharging according to the depth of discharge selected as we learned in the batteries section of this course. Also, it contains sensors that will protect the battery from high temperatures in order to increase the lifetime of the batteries. This is also known as the battery temperature sensing unit. So as you can see here in this figure, we have our charge controller, which is between the solar panels and our batteries. So you can see we have here two inputs, the positive terminal and negative terminal, which is coming from the solar panels, the positive and negative. Also, we have the two terminals going out to the battery, which is a pulse of the battery and negative of the battery. And of course, we have two additional terminals, which can be used to provide electrical power to DC loot. Of course, as you know, as we learned in the course, that we connect or we connect our inverter between these two terminals of the batteries. The postive terminal and net. Here we connect our charge controller. Here we connect our inverter. Okay, And as you can see, we have two main types. The first one, which is called the MBBT, or the maximum PowerPoint tracking charge controller, and second one is called the BW M or the pulse with modulation charge controller. Now, if you look at these two from the outside, the look similar to each other. You can see here this one similar to this one from the outside construction. You can see we have two terminals for BV, two terminals of four battery. Here we have two terminals of four BV and two terminals of four batteries. And as you can see here, the difference is the inside construction, which we are going to discuss in the next lessons. What are the types, we have As in the modulation charge controller, and second one, which is the maximum powerpoint tracking charge controller. 43. PWM Charge Controllers: Hey, everyone, in this lesson, we will start talking at the first type of charge controllers, which is a pulse weeds modulation or BW. So what is the pulse width modulation, gy controller. So BW M stands for pulse width modulation. So instead of having a steady output from the controller, it sends a series of a short charging pulses to the battery, a very rapid on and off switch. So what I mean by this exactly? If you look at here, we have our BV panels connected together and the two final terminals of the string is connected to our pulse with modulation controller. Let's say we have here, for example, we have 54 volt. Now, what does the pulses modulation controller do? It simply converts this one into group of pulses. Here, we will have a periodic time t or our time t, and as you can see, we have a certain time in which we are on, let's say 54 volt, Another time of equal to zero voltage. Then again increasing to 54 volt, then again, zero, and so on. You can see this series of pulses on and off, you can see this part is called the periodic time one period. On period consisting of a part, which is on on state and a period in which we have of state. The longer this pulse, the higher the out voltage. The out voltage of the pulse with modulation signal would be the percentage of the duty cycle. For example, if our charge controller uses a duty cycle of one or 100%. What does this mean? It means that it will give all of each voltage. It means that the voltage at the but terminal will be equal to, 100% duty cycle will be equal to the same as the input, which is 54 volt. So you can see here if the operating voltage is five volt, then the but voltage will also p five volt. Now, if the duty cycle is 50%, it means we will just take 50% of the input. It will be 54 45, sorry 45, multiply it by the duty cycle, which is 0.5. This will give us the out voltage. Again, the duty cycle representing the percentage of the on state with respect to the whole period. Again, duty cycle will be equal to t on the time at which the controller will give the full voltage divided by the periodic time. By controlling this percentage, by controlling the duty cycle, we can change the output. Also, you have to understand that the controller itself has a certain frequency. You can see this one called the periodic time. The frequency of the controller is equal to 1/3. Now, pi controlling the frequency or Pi controlling the periodic time, we can change the width of the pulses, width of the periodic time itself, by increasing it and decreasing it. All of these factors, the frequency, and the duty cycle, both of them will, will it change the but voltage. This depends on the state of the charge. If it is at the beginning or at less than 80%, it will provide longer pulses. Or will give high voltage. If a charging state is greater than 90%. For example, it will start giving shorter pulses. As you can see here, the duty cycle for a 12 volt, for example. You can see 0% duty cycle, it means it does not operate at all. Remember that the but voltage but voltage, V output is equal to duty cycle, multiplied by V input. So as you can see here, duty cycle here zero, it will give us V out will be equal to zero. Now a 25% duty cycle means that 25% of the whole period. You can see here, this is one cycle, another cycle, another cycle, and so on. So you can see 25% of the whole cycle is on this small period. 50% means 50% of the whole cycle, 50% on, and 50% off. 75 duty cycle means 75% on and 25% of. 100% means it is on all the time. Okay. Here is the controller. How does the controller choose the duty cycle and choose the width of the pulse, and the frequency, it depends on the state of the pottery. So the controller constantly checks the state of the pottery to determine how fast to send pulses, how fast the frequency, and how long the duty cycle or how long or how wide the pulses will be. In a fully charge a battery with no loot. Here we don't have any connected loot, fully charged. What does this mean? Fully charged? Means state of a charge 100%? What it will do? It will not provide volts except every few seconds. You can see it may just take every few seconds. For example, it will be like this and send a short pulse to the battery. Let's say, for example, you will have a period of, then a small pulse like this on. Then off a small pulse. Why do we do this in order to keep our battery at 100%? Okay. However, if the battery is discharged, for example, the pulses would be very long and almost continuous. As you can see, if the battery, let's say, for example, at a 50%, then the pulse would be like this. Very large period on like this, then very large period on, and so on. It depends on the state of a charge. Don't worry, don't have to do anything. The pulse with the modulation or the controller itself does all the job required. Now, what are the advantages of using a pulse width modulation charge controller? Why do we go to something like this? Number one, these controllers are the cheapest type of controllers. They are inexpensive. Usually selling for less than $350. Number two, pulse width modulation controllers are available in size up to 60 s. The maximum amount of counts that you can provide or the maximum rating that you can find in the market is 60 s. Or 60 am pairs. The pulse hizo modulation controllers are durable. They have a passive heat sink stye cooling. They don't suffer from high temperatures or they have a cooling system in the form of a heat sink. Similar to the power electronic device. It is in the end, the pulses modulation is simply a or power electronic device. These controllers are also available in the market in many sizes for a variety of applications. Now, what are the disadvantages of using the pulse modulation charge controller? Number one, there is no single controller size of 60. You don't find in the market a charge controller or a pulsi modulation of a current greater than 60 s. Number two, the pulse width modulation have a limited capacity for system grows. What I mean by this, this pulse width modulation are used for a very small systems. Number three, you'll find the biggest advantage regarding the pulse width modulation is that it has suffered from loses up to 30%. Now, why is this because the voltage will be reduced and the current will remain constant, so the power would be reduced. We will understand this statement in the next slide. Don't worry about this. Why does pulse with the modulation suffer from high losses, and that's why I don't recommend buying pulse with the modulation. Even if you are going to pie maximum power point tracking with a more expensive, which is more expensive, but I don't recommend pie pulse with the modulation. Now, why is this Now, the problem is that the solar panon volt is bolted down to match the battery volt? Whatever the voltage of the penan it will be similar to the battery voltage or the state of the charge of the battery voltage. Okay, so let's understand this statement. So we have here Paul Swedes modulation, Charge Controller. And we have here our panel, as you can see here. The voltage at maximum power, maximum power point is equal to 32 volt, and current at maximum power point is equal to 7.8 pairs. So let's say we are in the conditions that can provide maximum power. So we have the current at maximum power is equal to 7.8 pairs. So the input current coming from the panel which is similar to the maximum power point tracking current, will be similar to the out current. Both of them are similar to each other. No difference. But let's look at the voltage. Our battery voltage, let's say it is 12 volt. In this state of a charge. If it has a 12 volt, it will force the pulse with modulation forces the panel to be also 12 volt. You can see that the voltage at maximum power is 32 volt. However, the pulse with the modulation brings down or pulls the panel voltage to 12 volt, which means we will have a large losses in power. The voltage of the panel terms is not optimized for producing the maximum power of the panels. In order to have maximum power of 250, we need a current of 7.8 and voltage of 32 volt. The 7.8 is allowed by the pulse with modulation. However, the 32 volt is forced it to be 12 volt using the pulse with modulation. That is the biggest problem of pulse width modulation. Now, this pulls the panel volts away from the maximum power point or away from its optimum operating voltage V and P and reduces the panel a power output and operating efficiency. So let's understand this point. Let's say we have this panel, and this is the characteristics of this panel, the empire, the voltage and power. Now, as you can see the characteristics of ampere and volt, this is one this is the characteristics of the mpire or the current. Now, we have a current of 7.8 ampare, which is this point. Here approximately 7.8 ampairs. 7.8 ampirs. Now, what is the equivalent voltage here? If you go down here like this, We will have a voltage of 12 volt. Now, why is this point, 12 volt is forced by the season modulation. Suasion modulation, choose the value of 12 volt and current of 7.8. What is the value of power? You can see this red curve representing the power. The intersection between this line and the red curve, this point, representing the output power. The put power in this case is 100 vt. Why? Because because the pulse width modulation forces the panel to be operating at 12 volt instead of the voltage at maximum power point, which is 32 volt here, as you can see. 32 volt is a volt at which we will have maximum power of 250 watts. You can see how much power we lost due to the usage of pulse with modulation. We lost at a 150 watts. That's why I don't recommend using sew the modulation unless you are going to select the panels to have a voltage very, very close to the battery voltage. What I mean by this? If you have a battery of a 12 volt, then I'm going to select a PV panel with a nominal voltage of 12 volt. So that the losses becomes very, very small compared to this case. Now, let's talk a pot sizing of the poles with modulation, a charge controller. How can we select the current rating and voltage rating of this a charge controller? The pulse in the modulation is a controller that is very easy to size. It depends on one factor only, which is the current rifting. Current rifting, which is the maximum current that goes through it, you can see that the input current coming from the panel is similar to the current going to the batteries. Now, the current rating of this pulse with the modulation will be equal to the short sec current of the panel, of the panel, multiplied by number of parallel strings. Let's say we have a system like this. We have two panels in series. Another two panels in series. Like this, and the outbut will be like this, positive and negative, go like this, the positive and negative terminal, positive and negative terminal of the strings. We have one string and another string, and in the end, the positive like this, will go to here, the post of the panel, and negative here will go to the negative of the panel, like this. This a charge controller, which is a pulse with modulation, how many parle strings, we have one and two. Number of para strings will be two. What about the short circuit count? We see the short circuit count of one panel, short circuit count, eye short circuit coming from this panel, which is similar to, of course, this panel, because we said we are going to select PV panels, which have the same ratings. So it will be two, multiplied eye short circuit. Multiplied by a factor called 1.25. Now, what does 1.25 mean or what does it represent? It is a safety factor from the NEC NEC cod or the national electrical code. What does this factor represent? 1.25? It is related to something which we call the over radiance condition. Sometimes that this panel, 251 and this current is at one and one perimeter square and temperature of 25 Celsius degrees. In some cases, you will find that the radian irradiance can exceed 1,000 perimeter square. And sometimes the temperature can exceed 25 Celsius degrees. These two conditions or the over radians and high temperature, what do they will do? They will lead to increase in the current. If the temperature increased beyond 25 celsius degrees, let's say 40 Celsius degrees, In addition to the increase in temperature and increase in radians, which is called over radians and high temperature, we need to add a safety factor of 1.25 to accumulate for this condition. Now, remember that if the current, let's say, for example, if this pulse with modulation is 30 pairs, if for any condition for any condition, the current coming from the panel is greater than 30 pairs, let's say 31 pairs. What will happen to the pulse width modulation? This pulse width modulation will be damaged. It will be completely destroyed. You have to add a safety factor to compensate for the increase in the radians for any condition and increase in temperature for any other condition. That's why we add this safety factor of 1.25. Let's say for example, also, another thing which we have to consider, if we have a battery of a 12 volt, then I will select a panel with a nominal voltage. We learned about this nominal voltage P four in the panel, the section. So what does a 12 volt mean or a nominal volt mean? It means that our panel is capable of charging at 12 volt battery in the worst conditions. So we don't add two panels in series to form a 24 volt. No, it is completely wrong. Why? Because our pulse with the modulation will force the panels to go to 12 volt. So half of the power will be wasted. So we have to select a voltage of the panels close to the voltage of the battery, nominal voltage, close to the battery. If we have, for example, a 24 volt system voltage, then we need to connect two series panel, 212 nominal voltage series panels to form a 24 volt nominal voltage, and so on. We try to keep the voltage of the panel close to the batteries in the case of the poles with the modulation. Remember, we are talking here about poles with the modulation. So this does not happen in the maximum power point trek. In the maximum power point trek, I can connect whatever I would like. In the end, it will change both of the current and voltage. That's why I recommend always boeing a maximum power point trek. Another thing is that you can see here that the current ting, which is what you can see here, if the panel provides current greater than this value, then the pulse with modulation will be permanent. However, in the case of the maximum powerpoint tracking, you'll find that we have something which we call the charging current ting. The charging current ting, let's say, for example, 60 pairs in the maximum powerpoint tracking, if for any condition, The panel provides more power, and the current should be, let's say, 65 mpirs. The MBVTy will not be permit. It can withstand this. It will also give sect empairs. It will not be damaged, similar to the pulse with modulation. We will see this when we go to the sizing of the maximum power point tracking. Now let's see an example on sizing the pulse with modulation, charge controller. So if we have a system consisting of four polar strings with a short circuit current of 8.68. We have four polar strings. Each one have a short circuit of 8.68. Now, how can I select the pulse with the modulation? Simply the current rating will be 1.25, the over radians or high temperature in the C safety factor, Multiplied by the short cc current, which is 8.68, multiplied by the number of parle strings, which is four per strings. So we'd need at least a charge controller with a rating of 43 point 4:00 A.M. Pair, anything higher than this value. In the end of this lesson, I hope that you understand now the pulso modulation, how does it work, the sizing of the pulsi modulation, and everything is clear right now. 44. MPPT Charge Controllers: Hey, everyone. In this lesson, we will talk about the second type of charge controllers, which is known as the Maxima Power Point tracking or MAPPT charge controller. What is the BPT BPT charge controller? The maximum PowerPoint track in charge controller, they are the ultimate controllers. They have high efficiency between 94% to 98% range. They can save a considerable amount of money on the larger system, since they can provide ten to 30% more power to the pattery. If you compare this one to the previous one, which is a pulse with modulation, the BW M had lots of loses, high losses. Which can reach up to 30%. However, the maximum powerpoint tracking benefits or takes or uses all of the energy coming from the BV pans, without any kind of losses, except a small losses inside the controller itself. What happens exactly that the maximum power point tracking, it will reduce the voltage coming from the PV panels to the value suitable for charging the battery and at the same time, will keep the current at high value. Now, let's understand this point. As we'll see right now, the power will be almost the same as we have very small losses occurring inside this controller. Unlike the pulse with modulation in which we had a large amount of losses up to 30%. What happens exactly the charge controller or the maximum power point track and charger controller configures or change the voltage of the panel in order to produce the maximum power. It controls the VM or the voltage across the panels in order to always getting the maximum power from the PV panels. Let's understand the advantages and how does it work? Or some nodes regarding the maximum power point tracking. The first one is that the maximum power point tracking controllers offer a potential increase in charging efficiency up to 30%. These controllers have the ability to have an array with a higher in bod volte than the battery pack. If you remember in the pulse with the modulation, in order to charge at 12 volt battery, with a pulse with the modulation, we had a panel, PV panel. This panel should have a nominal voltage, a nominal voltage of 12 volt. However, we cannot add higher voltage panels because it will lead to power losses in the les with the modulation. Here in the maximum power point checking, we can add up to, let's say, for example, we have 240 volt coming from the panel, and we have MBB t, BBT that will be connected to the 12 volt batter. It is okay. So I can accept large amount of voltage. Higher v voltage, then the battery bank. It has a size up to 80 pairs compared to the pulse with modulation, which had only 60 mpeirs. The maximum power point tra gives us great flexibility for the system growth. You can add large amount of pales in series and parle, depending on the rating of the charge controller. However, the pulse with modulation keeps or limits the amount of patter amount of peels in series because we should have the same voltage or the same nominal voltage as the battery. Now, what are the disadvantage of using the maximum power point tracking charge controller? Number one, the maximum power point track controllers are more expensive and sometimes can reach up to two times the pulse with modulation controller. The MVPT units are generally larger in physical size than the pulse with modulation. Now, why does maximum power point tracking? A charge controller have lo loses compared to the pulse with modulation. The maximum power point point are far more advanced technology than pulse with the modulation, echogy controllers, and they enable the solar panel to operate at its maximum power point, or more precisely the optimum voltage and current for maximum power output. Let's understand this point. Remember this PV panel, and here when we had pulse with the modulation, When we had the BW, we had the 12 volt here, and the panel is forced it to be also 12 volt. For the current, we had 7.8 pair here, which is similar to the output, which is 7.8 pairs. In this case, as you can see here, what will happen exactly is that the sit the modulation will lead to a large amount of power losses. You can see that if you multiply this two together, you will get 100 watts. At the same time, our panel is 250 watts. In order to solve this, we have the maximum power point tracking. What does it do? We have different voltages and currents. You can see here at the battery side, we have 12 volt. Or any kind of voltage, let's say 12.8 or 13 volts the voltage are required for a charging the battery, depending on the state of a charge as we learned in the battery section of this course. Now, what at the panel itself, for the panel, you can see that we can control the but volte from the panel at the maximum power point. You can see it is at 32 volt, converted to the pulse with the modulation, which force is the voltage to be similar to the battery. So the maximum power point tracking has the function or the ability to form two different voltages. Here, different from this one. The second thing is that you can see that the empire itself here is the same empire at the maximum powerpoint. 7.8 empires tabla by 32 gives us the 250 watt. It means that our panel will produce the maximum power of 250 watt. Now, what happened to maximum powerpoint tracking at the battery site? You can see we have 12 volt here. In order to keep the 250 watt and pass it to the battery without any kind of losses, you can see 32 volt drops it down to 12 volt. The current 7.8 drops or increases to 20.8. 20.8 taped by 12 is approximately 250 watt. This charge controller does not allow any kind of losses. As you can see, all of the power transferred from the panels to the batteries do losses by increasing the current and stepping down the voltage. They are more efficient than pulse with modulation as we talked before, and it depends on the battery and operating voltage of the solar panel. Now, if you look at the curve with respect to a maximum power point, you can see 32 volt and the current of 7.8 empire at this point is the maximum power point. Our charging controller controls voltage here in order to be operating at the maximum power point. Now comparing these two together we talked up before, the ts with the modulation and the maximum power point tracking. Let's compare between the two. As you can see, we have this panel and this panel, you can see here two volt and 7.8 ampers. Here we have 12 volt and 20.8 ampers the power input is similar to the output, you can see. We are operating at the maximum power point, so we are getting the maximum power. Here you can see that the voltage is the same 12 volt and 12 volt, and the current is also here not at the maximum power point. You can see if you look at 12 volt, The operational voltage will give us a certain opposite current, which is 7.8 or approximately eight pairs. Okay. Now, the most important part here in this las on is, how can we size or select our maximum PowerPoint tracking? We have three ratings that we look at when we size the charge controller. Number one, the maximum int voltage, which can be connected to the charge controller, coming from the panels, number two, the maximum short circuit current, maximum short circuit current coming from the panels. Number three, the maximum charge current or the maximum t current coming from the charge controller. These three ratings determine the connection of the panels in series and parents. Depending on the charge controller and the rating of the charge controller that we select, we will be able to determine the connection of our panels in series and par. Now, for the but current, here, our current, which is the maximum charge current rating, this part representing this one. What does lit current rating mean? You can see here we have our batteries going here, the maximum charging current coming from the charge controller. That is what we say what we refer to as maximum charge current or the Albit current rating. Now, how can we get it? It will be equal to the maximum charging current, which is equal to the power of the PV panels, all of the power coming from the PV panels. Divided by the battery system voltage. As an example, if we have a PV panels or a group of PV panels, producing 2002 kilowatt of power two kilowatt peak. Let's say our batteries are connected into 24 volt system. By taking the two kilowatt and dividing it by 24 volt, we will get the maximum charging current going to the batteries. That is the first rating. We select this one, select a suitable charge controller depending on this value in the datasheet. Now we have to understand that some designers or some solar designers decide that they can add a safety factor of 1.25. It is not necessary to add this factor, but you can add it. Now, what's the benefit of this one? This for over radians, F over radians, similar to our bolts with the modulation sizing. If you remember in the pulse with modulation charging, sizing, we added 1.25 called the NEC national electrical code over radians factor. Sometimes our radians on the BV panels can exceed 1,000 watt permere square. Sometimes it can exceed 1,000 wa permit square, so the current will be higher coming from the panels. We can add or the power generated can be higher more than two kilowatt. So we add a safety factor of 1.25 to accumulate or in order to prevent any kind of losses. Now, a question for you. Let's say two kilowatt divided by 24, let's say, let's say for example, give us, let's say 30 empirs. As an example, not 30 mers, but just as an assumption. Let's say 30 emper. Let's say that the power coming from the panel increased beyond two kilowatt. Let's say the current in this case will be 35 amps. The charging current. We have a charge controller with a maximum lit current of 30 ampers more power came from the PV panel to the charge controller. In this case, it should give 35 pairs. What will happen to the charge controller since its rating is 30 pairs, nothing will happen. What will happen exactly is that the charge controller will give a maximum bit current of 30 pairs. Instead of 35. So the extra five empirs will be clipped. The og controller will not be damaged. It will be will not be damaged. It it will just clip the extra five empirs, o? The second rating, which is called the voltage rating. Maximum voltage, open circuit voltage of the solar panel. Since we are connecting, this is the voltage coming from the panel, maximum voltage of the open circuit voltage. What I mean by this is that we take the open circuit voltage of the panel, and multiply it by number of panels in series, number of series panels, because all of this will increase the open circuit voltage. Multiply by temperature, compensation, coefficient. What does this mean exactly this coefficient is related to that temperature. Let's say, for example, the open circuit voltage of the panel is rated at 25 Celsius degrees. Now, if the temperature goes down to 0 Celsius degrees, what will happen to the open circuit? O open circuit voltage will start increasing? So we have to multiply by a certain factor called the temperature compensation coefficient, which will be obtained from the BV panel data sheet or from the NEC, 690 table. We talked about this part how to get the maximum open circuit voltage at the worst conditions in the first section of the course of the solar energy course in the section of the panels, and the temperature coefficient, we all talked about it. Now, we will apply all of this when we design the BV system, when we design the off grid system, we are going to apply this coefficients. Now, the maximum input current rating, maximum current input two, the charge controller. It will be 1.25 multiplied by i short circuit, multiplied by number of power strings. Now, some charge controller doesn't have this feature. What I mean by this, some charger controller does not have maximum int BV panel short circuit. If you have a charge controller input current, you will need to add it using this. Okay Let's understand this point. You can see here these are different charge controllers, one, two, three. You can see rated charge current, 70 apares. Now, this rating, 70 pairs or 85 or 100, representing which rating representing this one, which is power of the PV panels, divided by battery system voltage. Depending on this value, we will select 70 or 85 or 100. Second, one voltage rating, maximum open circuit voltage, which is V open circuit, multiplied by number of panels in series, multiplied by temperature, compensation efficient. You can see here, maximum V open circuit voltage, which can withstand, or at which the charge controller the value that the charge controller can withstand. You can see his 150 volt, add the absolute maximum absolute maximum coldest conditions. It will be 1.25 multiplied by s here. It will be open circuit, multiplied by sears, multiplied by, temperature coefficient. It should be less than 150. Maximum input current coming from the panel, you can see here BV, maximum BV short circuit current, 50 pairs, 70 pairs, and you can see the reserve rating for each MC four connection. You can see, for example, that if you go down here, it is not clear here. If you look at this two, if I remember correctly, the two charge controllers have two MC four connection. Two MC four here and two MC four. You can see maximum 30 MC four connection. For each MC four maximum of 30 pairs, and the total maximum is 50 pairs. Depending on this value, it should be less than 50 pairs. Now, if you have a 60 maximum power point charge charge controller, which I'm talking about, the charging current, 60 pairs. If the current for at any condition over radians, the charging current is more than 60 pairs. The charge controller will still give the 60 pairs. However, the extra energy, which is the five, the extra energy, which is translated into extra pairs will be wasted. Nothing will happen to the maximum power point tracking, but this extra energy will be wasted. However, however, in the pulse with modulation, it will be damaged. You have to make sure in the pulse with modulation. I must withstand the current. However, maximum point tracking, it can clip the extra energy. If you don't want to waste any kind of energy in the case of the over radians condition, you can just multiply the charging current by 1.25. Now, as you can see in the charge controller here, the last one, 150 100. What does this two mean? 150 representing the maximum open circuit voltage, and 100, representing the maximum a charging current. You can see BV one, two, three. It can take from three strings, one string, two and three. As you can see here, this is 1005000. If you go down here, here you can see three pairs of MC four connectors. The pairs of MC four connectors. One, two, and three. I hope this lesson was clear for you in understanding a pot maximum powerpoint tracking a charger controller, and how can we size it? 45. Function, Types, and Data Sheet of Inverter: Hi, everyone. In this video, we would like to discuss the function of the inverter. In the solar energy system and types of the inverters or the inverters. First, what is the function of the inverter? The inverter can be used in converting the DC input voltage or the DC input coming from the BV penns or from the batteries, into AC power, which is used for our AC louts. Simply it converts the DC input into AC output. The DC input which have a fixed value like this, like this. This is our input. By this, the voltage with time. Constant the value with time. This is the value which comes from the BV panels or from the batteries. And converts it into sinus sodial wave like this. The albut should be a sine wave or AC, or it can be like this. The first one, this one is a pure sine wave, pure, which does not have any harmonics. But this one is modified sine wave like this one. You see that it looks like a ladder. This is also a sine wave, this one is also a sine wave, but modified sine wave, not a pure sine wave have harmonics. Of course, the pure sine wave is better than the modified, but the modified is aber than the pure sine wave inverter. The inverter is an electrical equipment that converts the direct current or the AC or the DC direct current from the batteries or from the BV panels into an alternating AC current or alternating current or AC, which is used for AC loads as in our homes. AC loads such as the motors, the, the lightening, the air conditioning, everything, every appliance inside our home is depending on the AC. You see that here, this inverter, DC to AC. You'll see that here, the, it's not clear so much, but the ut here is 220 volt AC. The ut of the inverter here, which comes from this socket or this branch, this part is the ut, the three part is the line neutral and the earth. This one is the, the t is 220 volt AC and the frequency, 50 or 60 her, so it is able to produce both of the 50 hers frequency or 60 hers frequency. Now, the first type of the inverters is or the grid in grid or grid inverter. What does this inverter do? You'll see that here in the grid connected system where our BV panels is connected to the grid and connected to our home. The inverter here takes the DC from the panels. And converts it to AC, which goes to the grid or the utility, and at the same time goes to our home in order to fit our appliances. The inverter produces AC power from DC and provides it to the grid and to the customer. You'll see that here another diagram, the PV panels, DC voltage, goes to the inverter. Then the inverter converts the DC into AC, which goes to the main distribution port for our home or C panel for our home. And this panel is also connected to the utility in order to take power from the inverter or supply power from the utility to the consumer. You will find that here in the grade system, we use a technique called the net metering. The net metering here, it is a difference between the generated power and the consumed power. For example, if our BV panels produce higher power than my own consumption. The panels that produce higher power or higher energy, then the consumed energy required. The difference between them, the difference between the generated power and the consumed power will go to the grid. We fed power to the utility. We give power to the utility. Now, in case of having low power or low generation of BV panels. In this case, we need more power to fit our louds. In order to do this, we absorb the power from the grid. So the meter here sees the difference between them. For example, if the power going to the grid, then the power goes from the inverter like this to the grid, and if from the grid to the house, then it will be like this. This one is a generated power to the grid, and this one is a consumed power from the grid. The difference between these two powers is the amount of energy, which is the customer going to B. The grid i inverter converts the direct current or the DC current into alternating current. This alternating current should be suitable for injection into an electrical power grid. Of course, the inverter should be automatically synchronized with the grid. We cannot connect an inverter with the grid without satisfying the BV code or the synchronization conditions. The value is normally 120 volt RMS at 60 hertz or 240 volt RMS at 50 hertz. You'll find that the requirement of connecting a inverter to the grid depends on the BV code or the photo voltaie code. For example, in my own country, Egypt, the phase difference between the phase difference, the angle of the AC generated, so the difference between it and the utility can be up to 2020 degree difference between them and the frequency difference between the inverter and the utility up 2.3 hertz. The difference in voltage, as I remember, plus or minus. I think 5% because there is a for that distribution and for the B V or the photo voltaic. Plus or -5% of the voltage. The total harmonic dist, on or the total harmonistortal in factor should be as I remember also 5%. Also the injected DC current by the inverter should not exceed injection, injection should not exceed point Y percent of the AC rated power, AC rated power, rated power. You will find that according to your own code, the BV cod according to your own country because it differs from one country to another. For my own country, the phase difference between the inverter and the utility should not exceed 20 degree. The frequency difference should not exceed 0.3 hertz. It can be higher than 50 hertz, for example, 50.3 or 49.7. Let's Pi 0.3 or higher Pi 0.3 hertz. And the voltage should not exceed plus or -5% of the utility voltage. The total harmonics should not exceed 5%. The DC injected by the inverter should not exceed 0.5%. Also find something here that the inverter in our country, the BV system should be three phase system. We cannot connect a single phase. There are always three phase. Why in order not to increase the unbalance or the imbalance in the utility. Because if we injected a single phase, so one of the three phases will be overloaded, other than the other three phases. The other two phases. We have to connect a three phase balanced system or a three phase balanced solar system to our grid. And the minimum connected power in Egypt, for example, five kilowatt. Because the five kilowatt is a three phase system. Now, these values of course, can change according to your own country. You have to see the BV cod of your own country in order to understand the conditions required of connecting the inverter to the utility. Remember also that you cannot connect an inverter to utility without a certificate. You have to be an installer, which is certified by the renewable energy agency. You cannot just connect as a normal person to the utility. You have to have a certificate or become a certified installer according to the agency itself or the renewable energy agency itself. Also, in this system, the grid connected, we don't need any batteries because we take power from the utility. In case of the absence of sun, we take power from the utility or if the solar panels does not generate enough power. No patter is required to store any energy here. In this system, we use net metering. Net mattering is the difference between generated and consumed, use net metering technique in which the customer is paid according to the difference between the generated energy and consumed the energy. The meter of course, calculate the generated and consume the power. In order to inject electrical power efficiently and safely to the grid, the grid Ti inverters must accurately match the voltage phase of the grid sine wave AC wave four. Of course, we said before the conditions of synchronizing the inverter with the grid. Both of them should have the same voltage, same phase shift, or according to your own code, it can have a small deviation or a small difference between them. For example, plus or -5% of the rated value of voltage and phase difference of 20 degrees. This can differ from one country to another. In case of faults in the utility or the grid, the inverter automatically shut down in order to prevent hazards to maintenance crew in the grid and public safety. What does this mean? It means that let's see here what will happen. Assume that we have a fault in this transmission line, a fault connected to the ground, or one of the phases connected to the ground. Now, what will happen? We disconnect the circuit breakers, which is related to the transmission line. The power on the transmission line in this case or the distribution system in this case, because we are connecting here to distribution system. In this case, the power will be equal to zero because the phase here connected to the ground and wiscnect the circuit breakers. Now, what will happen if someone comes here, a little person here, like this. This one wants to fix this pro line, this broken line. Now, the maintenance crew goes to the prokin transmission line or the Procen distribution line. Now, what will happen is that when they come to touch this one, they may expose the two electric hazards. Why? Because we have the inverter here, which will provides power to the appliances at home and provides power to the grid. It will inject electrical power to the grid, going to the maintenance crew and give them electric hazard. In order to prevent the electric hazards from the inverter at my home, the inverter when grid itself have a fault or have a problem, the inverter is disconnected automatically from the grid. No electric hazards will occur. Now, here is an example of the grid Ti inverter. You see that this one has a power of 500 watt or 0.5 kilowatt. You'll find that the maximum, this was this grid ti inverter. You remember that we don't have any batteries. We don't have any charge controller. The grit Ti inverter here contains the inverter plus the charge controller. It have the two techniques together. You see that here, it works in the maximum PowerPoint tracking technique range of the DC inot 18-48 vs. This is the inbot from the panels and it automatically has a charge control in order to charge the inverter itself to convert to AC. I'll find that the Ibo DC range, the range which can satisfy 15-60 volt, and the recommended or the value at which we can produce the maximum power is 18-48 volts. This is the maximum power point range DC. You'll find here that let's delete all of this. That the value of the voltage which produces the maximum power is 35-39 volt, and the open circuit voltage is 42-46 volt. Here, this value, 35 to 39 is is the voltage, at which we can produce the maximum power. This one is the value of the voltage, we can produce the maximum power of the inverter, this value is the range of nearly maximum efficiency, but the maximum value is at 35 and 39 volt, at which it will produce the maximum power of 500. The output of this inverter is 230 volt, and the range can be 190-260 volt. Now, we will find that this inverter have two inputs. On which is the red and one which is the plaque. What does this two represent? The red one representing the positive of the collected all of the BV panels, or if we have an of grade system, then it will be the positive of the batteries, and the negative here representing the negative of the panels. Now, this one will produce an but AC, which is suitable for our loads or connection to the grid. Now another type is called the grid system or the of grid invert. This type of inverters is used in the of grid system or the system which is not connected to the grid. You'll find here a group of solar panels, which is connected to charge controller in order to charge the batteries. Charge the batteries. Then after charging the batteries, we take from the batteries to the solar inverter or the of grid inverter and provides power to the consumer or the user. Find here the power inverter, a pure sine wave. Pure sine wave y pure sine wave in order to increase the lifetime of our equipment. This one is two k. This is the output power. You'll find here this one is line and neutral, and the earth, line neutral and earth. This is the inverter, this is the but, this is the but of the inverter here to fit our loots. And the Ibut comes from the other side. Now you can find that this one is a pure sine wave, the pure sine wave is this one. This one is the pure sine wave. And the lather form here or the step form, this one or the modified is a modified sine wave. The sine wave or the pure sine wave is better for the lifetime of the equipment, but it is more expensive than the modified wave. The solar panels fit DC power into the batteries. Solar panels provides power to to the batteries using the solar charge controller. This system is of grade or not connected to utility. Of grade, it means that it is not grade Ti or not grade connected, so it's not connected to the utility. It is used in places which have geographical obstacles, making it difficult to connect to grid. If if I am presenting in a location, which is consisting of mountains or does not have any or is difficult to connect to the grid, expensive to connect to grit. We use the off grade system in order to provide power to our home without it depending on the utility. The inverter takes that power and inverts it takes the power from the battery and inverts it to AC. AC is the output and the input is the DC input, DC. It provides AC power for our home. This system need the batteries in order to feed loads at night. Because our sun presented at day light only, and at night, we need to provide power to our home. We use batteries in order to store the energy for using it at night. Of course, in this course, we will learn how to design the upgrade system and the grade system, and we'll know how to select the solar panels, the surg controller, the batteries, the inverter, everything about this. The pure sine wave inverter is better than the modified part, higher cost. The pure sine wave causes the loads to have higher lifetime than the modified wave. Now, before we go to the hybrid inverter, we will go now to a video which shows you how to connect the grade inverter. Now, here is a symbol video, which will show you how to connect a power inverter or sitting up an off grid solar inverter. Now, this video is provided by the do it yourself word channel. Now, someone will ask me, why do you provide us videos from YouTube or showing us videos from YouTube? Because those channels provide help for videos, which can help you not in solar energy, but in other categories. It is helpful for you to subscribe to different channels in order to learn from them and increase your own knowledge. That's why I show you videos from different channels, which show you a practical and it will be helpful for you in order to understand more. Now, this one is a pure sine wave inverter, power inverter. This one can produce a continuous power of 600. Now we'll find that the inbot voltage, 12 volt from the batteries, and Albert 120 volt AC six d hertz. This one is a fixed value, ino 12 volt, but 120 volt AC. The first thing you will find that here on this side, we have two parts, one which is the red, and one is the black. We connect the postive of the batteries to the red and the negative two the black. Now let's see this go here in the front. Now you'll find here that the positive and negative clear and helpful. DC 12 volt and negative is the plaque. Now this one, this wheel, and this one. You will rotate them anticlockwise in order to remove them and add the black or the positive of the battery. So see that here. We will remove it like this. Let's get back. You see that here, he removed the part by rotating like this, let's see, by rotating and he removed this. Anticlockwise. Now, the next step that we are going to add the positive here and the negative. Then we will add the wheels again. Like this, post negative which is the plaque and the postive which is the. Now, usually, you should put the plaque first or the negative first then the postive. Remember that when you put the postive, it you may find that there is a small spark according to the value of the wattage. When you connect it here, remember, of course, not to touch it, not to get an electric shock. By doing this, you connected it now the positive end negative. Now, then you can see that this inverter have two outputs, one which is the USB, which can be used to charge the batteries, and the other one, which is used to USB here port in order to charge the batteries. This one is used to connect the EC loots. For example, a charger for mopile or anything, or for laptop or anything, you can connect it here and use it to supply power. Now you can see that here, it is used the USP port in order to charge small component or electric component. Now, another one, which is the Lute, he connected the charger here to the battery. Connected it to another battery. He wants to charge this battery. Like this. In this video, in this small video, we learned about the of grid system connection. Now let's get back and see what is the meaning of the hybrid inverter. Now, what is the hybrid inverter? The hybrid inverter is primarily used for the grid tie purposes, but also has the added feature that they provide pack up power to your home when the electric utility fails. Remember that In the grid system, we took the power from the solar panels, connected it to the inverter. The inverter provides power to the grid and from the grid using the net metering technique, and the inverter provides power to our house. Now, we remember that at every all or the condition of all day or having the power all day, the inverter provides power from the solar panels during the daylight and at night we take the power from the utility. Now you will find that something difference here. The difference is that if we have a fold on the utility. We said that when we have a fault on utility, the inverter automatically disconnects from the grid. Now when it disconnects from the grid, we don't have any power to our house. In order to fix this problem, we add the feature of the grid system, which is the battery. We have the battery, we have the grid, and we have our home. The battery itself, or it can be AC generator, whatever it is, it is a pack up power. The customer often use the hybrid inverter systems with solar panels in order to keep the power going during a plaque out of the grid or a fault on the grid. We take the power from the solar panels to the inverter invertory charges the batteries. This one inverter includes, of course, inside it, the charge controller. It is integrated inside it. The inverter charges the batteries provides power to our house AC power by inverting the AC to DC, and at the same time provides power to the grid or takes part from the grid to our house using the mean distribution panel. Now, in case of the power output here or the outage of the power from the grid, we invert the power from the battery and t it to our house or our home. Hyprid power system is the pest of pos words. You never need to worry about being without power. We take the advantage of the grid system and the advantage of the grid system, off and on grid system together. Combined together, providing us with the hybrid system. But the problem of this system, it is very expensive because the patteres, we have batteries, we have our grad, we have inverters, we have more different components and difficult more than the grade and end of grad systems. Sometimes instead of batteries, we have generator. You increase the cost on yourself. Now, you'll see that here, an example of the hybrid inverter, this hybrid inverter, hybrid solar inverter. We have an LCD display in order to but the settings for the hybrid inverter. You'll find here the input for the battery inside it, battery input plus minus, positive anti negative, which takes from the battery, and we have the BV input terminals plus or minus from the BV panes. We combined all of our BV system and connect it to the BV inut here. So we have our BV plus and minus for the BV, the battery input plus and minus, and finally, we have our AC input and AC. The EC aut, which we can take from it and satisfy our loads or our passport and the AC input from the grid. So find that this is a hybrid which contains all of all components in one. You see here that it supplies our loads, takes from the batteries, or takes from the batteries or charge the batteries, whatever the case, and from the utility connected to the utility and connected to the solar B V panels. Now, another type of the inverters which is used in water pumping systems. We have a system which is very simple, we have the solar panel, provides DC power, of course, to an inverter, which is used in the solar water pumping cases. This one will provide power to a three phase motor or a single phase motor. This motor is a pump, which is used for pumping water. It can be submersible or underwater or surface motor or a surface pump. According to this, you can find the inverter amount of power required and from the solar panel required. We were also going to add the design of the water pumping system in our course. Now, another type of the inverters, which is used is a string and centralized inverters. What is the difference between them? This one is a string inverter case and this one is a centralized inverter case. Let's see the string. The string inverter what does mean? It means that for each one string, we have inverter. Find here one, two, three, four, four panels connected in series, forming one string, the positive, and we have the other side which is negative, which provides, of course, DC and connected to one inverter. Inverter here for this one string. For this string, one, two, three, four, connected in series. All of them having positive and negative connected to one inverter, and et cetera. What does this mean? It means that for each one string, we have one inverter. Then the but, which is the AC are all connected in parallel. Each strength have one inverter, and the final but is connected together. Now, in the centralized type, all of our BV panels are connected to one inverter. We have the string, barry to another string, barrier to another string forming an array, which have a positive and the negative terminal, and the dits in order to prevent the flowing of the current to the panels. In case of the output in case of no sun light, which means no output from the panels. In order to prevent the reverse but from the battery to the panels, we have to add reverse dites. Or plocking dies. Now you'll find that all of this which forms one array is connected to only one centralized inverter, one large inverter. Each string here is connected to one inverter, each string in the string inverter, each string connected to one inverter. Inverters are connected in bar. You see one inverter here, Barry to another inverter, bar to another inverter in barrel providing the total power. The high reli, high reliability in this case. Why? Because if we have, of course, if this inverter have a fault, then the other two inverters or the other inverters will still provide power to our system. We have high reliability, since they are all in parle, and if one is out, then the others will provide power. If one inverter has a ful, you just lose part of the power, not the total power as a centralized inverter. You see here in the centralized inverter, we have only one inverter. If a fault occurred in this one or a problem occurred in this inverter, then we lose that total power. But if a at occurred in the string inverter, only one inverter is out and all of the other inverter exists. But the problem is that needing larger space due to the requirement of large number of inverters. You see here in the centralized, we need one inverter just, one inverter. But in the string inverter, we need large number of inverters connected in parallel, so it will need large space. Due to having large space, then it will couse us more cost. Of course, a large number of inverters that means higher cost. In the centralized all strings are connected together forming largely. A strings are connected in barel forming one large array, which is connected to one centralized invert. The problem is losing the total power in case of the fault in the centralized inverter. I'll find that in case of the mega scale or large scale BV system, we use the string inverters a large number of string inverters like hundreds of inverters instead of using one centralized. Sometimes we use one centralized and sometimes we use string inverters. Both of them can be used in large scale or in mega what generation? Now you see here another image for this. You will find here that this one is a string, another string, another string, and all of the strings are bar forming one larger array. This string will provide positive ending to one large centralized inverter. To provide power is three phase power. Now in this case, we have one string connected to one inverter, string to connected to one inverter, string to one inverter, all of them are in parallel. We have a string inverter case and centralized inverter case. Here is also we can have one panel with one inverter one panel with one in one panel. In this case, this is called a micro inverter because it's connected with one panel only. This system has high cost, but high efficiency, and we'll understand it in the next slides. Now, we see that the central inverter, it takes the DC from all of the solar arrays or the solar panels, strings parallel to each other forming array or group of arrays. Then we have a combiner box to combine all of this power together. Then providing the positive and the negative to the central inverter, which will provides power to the grit. The string inverters group of strings in barel string number one, which provides to an inverter, giving AC, DC giving string str inverter and giving AC DC to inverter giving AC. All of these are in barel and connected to the grid. Now we understand the difference between the string type and centralized invert. Another type is the micro inverter. What does the micro inverter do instead of using a string inverter, which is used to take a string and invert it. We use a micro inverter. This one is used for each panel. One panel have one micro inverter, each panel have its own inverter. You'll find that it is a power sine wave but, sine with P sine wave but. You'll find here that it works with the maximum PowerPoint tracking technique. It has a charger controller inside it. The input can be 22-60 volt DC, and the output in this case, will be from 90 volt to 140 volt EC according to what according to the input to it. The outbut here is 50 or 60 hertz. Now you can find that here, we have one, two, this is the positive and negative. This is the DC input. Number one is the negative here, and number two is the positive. It comes from what comes from the PV panel. We take the male and the female and connected it to the DC inut here. Number four is used for antenna or it can be used for wireless communication in order to communicate with all of the micro inverter in order to control them or to get the data from them. You will find here it is working on the technique of the power line carrier technique or comic, BLC communication. Now we will find that this one, number three, this one is the EC. This is used to provide the EC b positive and negative. You see that in this case, we use one inverter, one micro inverter is used for each panel. It converts the DC Albo directory to AC suitable for the grid. High efficiency, but high cost of system, as number of inverters increases, as number of panels increase. Now you find here two schemes for the micro inverter. We have the single phase micro inverter, single phase scheme, and three phase scheme. So find here in the single phase, we have only one phase line and neutral. You'll find that the positive and negative goes to the inverter from each panel, and the inverter converts it into DC with align and neutral. Also Balan number two provides the positive and the negative to the inverter, the inverter converts it into AC with positive and negative, and et c n number of inverters. All of them are connected in parallel. Then it will provide us with line and neutral, which goes into a circuit breaker or a switch in order to turn it into off, and the meter to calculate the power provided to the grad. This meter, the amount of power injected to the grid is calculated by something which is called fed in tariff. What does fed in tariff means? It means that the amount of money or the amount of dollars or amount of cents bear each k hour provides to the grid. For each one k hour provided to the grid, I will take, for example, $1. This is just an example. According to the fed in, feed in tariff. Let's write it, so someone may ask me, feed feed in tariff. What does this representing this representing the cost or the cost. For example, dollar. For each, k or for each energy, kilowatt hour provided to the grid. This representing the cost in the contract with the grid or the utility, for each 1 kilowatt hour provided to the grid, how much dollar I will get. In the three phase electrical scheme, you'll find here that we have panel in panels and in inverters. Now in order to provide the three phase, remember that in the three phase system, we have the ABC, radio blue or whatever according to the system, the three phase system plus the neutral and the grounding for the protection. For the grounding, of course, connected from the inverter to it because it is a metallic structure in order to prevent the electric shock from the inverter itself. We have to provide the grounding against the leakage current. The panels connected here, providing A, this one AC, and this one AC. You'll find that inverter number one, for example, provides to phase number A and the neutral, phase number A and the neutral and the ground for protection. Invert number two provides for phase number P and the neutral, and the ground for protection. Number three provides to phase number C, neutral, and the ground. Then after this panel number four, it will be A and neutral. Number five, B, and the neutral, C and the neutral, and et cetera, y in order to provide balance on the three phase. Since it provides power to the three phase, we try to balance the three phase by providing inverters equally across the three phase. We find that group of inverters connected to phase A and neutron. Another group connected to phase B and neutron. Another group connected to phase C and neutral. This is how we can connect the micro inverters in case of a three phase system, and how can we connect them in case of a single phase system? Now, the inverter size and data shade. You'll find that the inverter size. Usually the single phase is less than ten kilowatt. The size available, less than ten kilowatt is a single phase. But the three phase can start from five kilowatt and higher. Sometimes you can find less than five kilowatt. Usually for large scale or mega scare, we use a three phase inverter, since the power in mega. In this case, we'll use a three phase system. Single phase is used for a small scale or small power generation. Now, here's an example of the inverter data sheet. This is a data sheet for a Sonny Poy inverter. Sonny Poy, which is a famous company for inverters. You'll find that here we have Sunny Poy 4,000 T L 21, Sonny Poy 5,000 T L 21. What does 4,000 mean? 4,000 means the amount of kilowatt generated at rated power. This is the rated kilowatt, rated what. 4,000 what is the rated bit power, or four kilowatt. This one is 5,000 kw 5,000 what or five kilowatt. You'll find that in the Sonny po, for example, the 4,000, you'll find that the rated power here, is the albut rated power at 230 volt and 50 hertz give us 4,000 what? Rated bower 45000 is 4,600. No 5,000, but 4,600. You'll find that the albut here the maximum apparent power, AC, the maximum AC power, the maximum S, the apparent power is 4,004 volt and bear. The inverter, remember that inverter can be used to provide DC power, sorry, not DC, but it can provide active power and the active power. Because it is an inverter. By controlling it by using different techniques, and in the inverter itself, we can inject active power or P and injectory active power or Q. The apparent power of them B plus jQ is 4,000 volt and bear. This is the maximum apparent power or S. The Sonny po 5,000, 5,000 volt and bear is the maximum power which can be generated. Maximum S f that the rated grade voltage at this rated power is 230 volt and this 1230 volt. You can also see that the nominal SC voltage, which can be controlled at 220 volt, 230, 240220, 3,204. This is the nominal SC voltage values. F that the equivalent current for each of them, the albut currents, 220 gives us 18.2. Higher voltage means lower power, lower and bare, because we need to provide the same amount of power. 230 volt AC gives us lower amount of current. 240 volt, 16.7 and bear. The maximum albo current, which can be provided by an inverter maximum amount, 22 for this type, and 22 for this type. Total harmonic distortion, which mean representing the harmonics in the AC voltage, less than f percent and less than 4%. In Egypt, it can be connected to the grit. Because the total harmonic distortion here is 4%, which is less than 5% which is required. Now, we'll find here also that frequency, 50 hertz, 50 hertz, the AC power frequency, 50 or 60, 50 or 60 can provide both of them. The range of AC frequency, can operate at a frequency 45-55 hertz. And for 60 s, 52, 62 65 ds. This is the range of the frequency which you can provide. This one is the range of the frequency which you can provide and connect to it or the connection to the grad, and the displacement factor cosine pi, it can be from the range from 0.8 lagging to 0.8 leading. All of these techniques is for electrical power engineers. Electrical power engineers can understand me well about this important data sheet. You can find here also the maximum power DC power, maximum DC power et cosine five equal one. What does this mean? It means that the maximum DC power, which can be given, which is 4,200 what and 5,201. What does this represent? This represent the DC power input from the pennants or from the batteries. To the Sonny po, the maximum is 4,200 and the maximum 5,200, and the albut is 4,000 what, and the albut is 4,601. The maximum power point voltage range. This is the voltage at which it will produce the maximum power. The range at which it will have the highest efficiency, from 175 volt to 500 volt, and the rated input voltage, the rated input DC inut 400 volt, which will provide us the rated outut power. The input 4,200, we will get 4,000 and the rated conditions. We will see in the next slide the difference when we have different voltage. The minimum inout volt, this is the minimum at which we have to provide to the Sunny boy, 120 volt. This is the minimum inbout voltage. The recommended is from 1,175 volt to 500 volt. In order to produce the maximum power, the maximum power or the rated power, we should operate at 400 volt. You can find here that the initial inbut voltage, 150 volt, at least which it could start. At least the maximum input current, 15 and be, 15 and bear, this is the maximum input which can be provided from the pennants or from the battery. In case of a short circuit, bear input bear one input should be 20 and be. This is the maximum short circuit. 46. Example 1 on Design an Off-Grid PV System: Hi, and welcome everyone. In this part of our course for solar energy, we are going to discuss the design of an off-grid PV system. A system which is not connected to the electrical grid. So in this system, when we have our solar panels that will provide electrical power to our house, or convert solar energy into DC power or electrical DC power. Then we have our charge controller that is used to regulate the charging of the batteries. So we need to size our batteries and we need to size our charge controller. Then we have our solar inverter that will take the DC power coming from the batteries and convert it to alternating current or AC voltage for our house. So the steps of design is as follows. Number one, we will first define our loads. We will look at our house and see what loads do we have? How many what how many hours do these loads work? Number two, we are going to size our solar invoked or paste on the wattage of our house based on some wattage, as we will see. Then we are going to size our solar panel that will provide enough power to our house and our batteries. Then you are going to size our batteries. We will select as a system voltage, and we will select the number of batteries in series and parallel. Then we are going to go to the sizing of the charge controller. This part or this device. We will know what is the ampere required and which charge controller should we select. After this? After getting all of the information, I apologize, sizing of the solar panels, the voter batteries, and the charge controller. We will be able to define that connection required for the solar panels. How many panels in series and how many panels in. So let's start by the first step, which is defining our loads. We looked at this. In this example. We will have a very small load or a very small house. In this house, we have several devices. You can see we have alarm, we have fan, we have refrigerator. And how many lamps? We have only one lamp, one fan, and one refrigerator. Now it's a power per device. How many, what each of these device is Alam each lamp is 18. What fan? 60 watt refrigerator 75. What? Now where did we get this inflammation? If we look at any device, you will find on that label. Label of this device, you will find how many, what, how many, what order you will find the voltage and current. And voltage and the current we can get our power, which is V out. How many wattage each device, then we have number of hours. How many hours does our device operate? E.g. here, we assume that our lamp will operate for 4 h. Our fan will operate for 2 h, refrigerator for 12 h. Then, using this information, you can see we can get the energy, how many, what our power and our which is representing our time. So power multiplied by time gives us energy. So our power multiplied by time, it gives us energy. So 18 what multiplied by number of lamps, multiplied by number of hours give us 72. What our similar here fan 16220, 1 h, and so on. Now what are we going to do is that we are going to get the total wattage here, the summation of all of these wattage of each of these devices. So 18, 60, 75 gives us 153. And then similar to the energy, the energy we are going to add, all of these energies, 72002000, and it will give us 1,000 mine to what our pair t. So we have the total energy required per day. And do we have the total wattage needed? The total wattage of all of our connected device. The first or the second step right now is sizing our inverter, the inverter that will take the DC voltage and convert it to AC for our house. Now in order to size an inverter, you said before that the inverter is used in the system where AC power output is needed. If our system is a DC system, then what I'm going to do, we're not going to use and invert. However, the inverter here is easy to take a DC power from batteries and convert it to EC for our volutes. Now is the input rating of the inverter should never be lower than the total what of our appliances here. So what I mean by this, so that inverter itself, how many watts? So it is measured in all its rating is how many, what or how many kilowatt. So this wattage should never be lower than as a wattage required by our, our house. So the inverter also must have the same nominal voltage as you Patrick. So if this system is at 24 volt battery system, then this inverter should be also at 24 volt invert. So what I mean by this, this inverter is designed or suitable for a 24 volt battery system. So we connect, we have to select an inverter that will provide enough power for our house. It's power rating greater than the total loads here. And at the same time, it is suitable for the same battery voltage. Now for stand-alone systems and vote on must be large enough to handle the total amount of water you will be using at one time. So we assume that all of the loads in our house are operating at the same time. There's a worst case condition. So in this case, we will size our inverter base that all of our loads are operating at the same time. Worst-case. Now full grid tie or grid-connected system, the input rating of the inverter should be the same as the PV array rating to allow for safe and efficient operation. Now what I mean by this, when we are going to design a grid-connected system, we have to make sure that that power rating of the inverter is similar to the solar panels or suitable for the same power coming from the solar panels. We will see this when we size our grid connected system. Now, let's go to the sizing of the inverter right now. So all of the previous slide is in general information. Now we need to know if we have this loads, how can I size my own inverter? So the first thing is that the power rating of the inverter should be greater than the total load. Load, total wattage by 25 or so to present. So what I mean by this, we will take this value and multiply it by 1.25 or 1.3. So our inverter would be larger than the total wattage of our loads by 25 or 30%. So we take this value and multiply it by 1.25 or 1.3. This will give you their continuous power. It's a continuous, continuous power rating of the invert. So from here we can see that the invert actin was powered will be 1.3 multiplied by total wattage, which is 1.3 multiplied by 153. What give us 198 point towards this representing what? Representing the continuous power, what I mean by the powers that inverter can provide continuously for a long time. Now, usually you will find that most of the solar design and nurse takes this value, which is almost 200 watt, and you go to the market and social for 200 watt or 250. What involved. However, you have to make sure of something which is really, really important because it can affect your own PV system. Something which is called the surge of power. Now what I mean by this surge of power rating of n invoked. Now, you will have to understand that there are some loads that contain maltose, such as pumps, compressors, refrigerators in the refrigerator, so e.g. or in the air conditioner. All of these devices have starting current. Since the z have a starting current. And voltage must withstand, this is starting count of the device. So as you can see here, we have a refrigerator with the starting current. So I have to design my own inverter to stand starting current of the refrigerator, which can be for a very short time. So this will lead us to another important property of Zara sizing of an inverter. Which is surge of power. So if the system has motors, compressors, refrigerators, pumps, washing machines, all of this, we need to make sure that inverter can withstand the starting current of these devices. So the surge power of this device is found on the label of them. You will find it in the form of a surge of power or an anomalous our way. You'll find it in the form of in the form of that looked rule to current, logged rotor, current or locked rotor and bear some single axis looked rule to this property, you will find how many amps, how many amperes during salting, and how many m's. On the same label, you will find how many amps during normal operation. And the ratio between them will give you how many times we are going to multiply our power of the refrigerate. Let's say e.g. that issue between if we look at the refrigerator and we look at that long to router current, divided pi is a normal current at normal operation. And we found it three times. Then the surge of power months to stand three x the 75 v. Okay? So we will see right now, if we don t know this value, what can we do? If we don't know this value of the surge of power, we can just assume that the surge of power is three x. Two for x is a wattage of all of these devices. So let's see this example. As you can see, we have a lab, 18 what, okay, So the inverter such power will be lab which is 18 what? Plus our fan, which is 60 watt. Now, if you would like to, if this fan, if you think this fan will have a very largest starting current, you can, you can multiply this by three times or four times as you would like. But in my case, I think that the fan is having a very small load, which will not have a very largest starting current, convert it to something like a refrigerator or a compressor or a pump and so on. If you would like to consider the fan having a larger starting current, you can multiply it also by three or four x plus four times the refrigerators, since the refrigerator has a starting current. So we will multiply it by four times. Now, where did we get four times? If you look at the refrigerator, the label of the refrigerator, and you'll find a surge of power or look the rotor current. Based on this value, you will be able to get how many, how much is the current adds a starting of this compressor of the refrigerator. Now if you don't know, you can just assume for x or for x as a power. So we assume the worst-case, which is four times that I wanted to refrigerate. Now, if we add all of these loads, you will get 378. What? Now is this? What does this mean? The search bar here means that if I start refrigerator, fan and lump all at the same time, then the inverter search bar, which is for a shorter time, should be at least this value. Do we understand all of these loads, starting current of these loads? Okay? How can I get this value simply, you can get an inverter with a continuous power of 198. So let's get back here. Here. Inverter continuous power one, line eight, which is in normal operation. And if you go down here, you will find the Search power of 378. So this surge of power is for a shorter time during the starting of the equipment or during salting of these machines. And the continuous power, which is one line eight point to mind, is for that continuous or for a long operation. So we would like our inverter with continuous of this surge of this. Now if we look in the market for something, for an inverter that is suitable for these conditions. We'll find something like this. This one forum. My vector on energy company vector is a well-known company for a charged controller. Z also have batteries, and they also have a solar charger controller. And here in this case inverted. So we selected here at pure sine wave inverter. And this is really, really important. You will find that inverters are divided into two types, modified, more defined. And there is also pure sine wave. Now when I'm selecting my own inverter, I would like pure sine wave is stay away for Modified, Modified can harm your own loads. So we always choose pure sine wave for our house. So it provides a pure sine wave as the modified can be a square wave like this. Hey, a square wave like this. And instead of a pure sine wave, so it's called a modified wave. So we always choose, we look for pure sine wave in what? Now as you can see here, 12 slash 250. So what does this mean? That, well, we're here representing the voltage of the battery. The voltage coming from the batteries will be in the system of a 12-volt. The system voltage is 12 volt. And 250 here representing what representing the continuous wattage. If you look at here, you can see vector on, It's really important to look at the data sheet. It is really, really important to get all of suspects. Now you can see vector on 250, what inverter, you can see 12 slash 24. So it's suitable for 12 volt battery system or a 24 volt battery system. You can use this or this as you'd like. You can see is that continuous power at 25 Celsius degrees is 250 watts, so it is a continuous power of the inverter. Now if you get back here, here you can see that the continuous power required is one line eight. So it is, so that 150 is higher than that require the value. Now second part, which is a surge of power or peak power surge or beak. You can see peak power 400 watts. So this is a power during the transient condition or during the starting of the loads. So it can withstand up to 400 watt of starting off, starting power of our loads. So here you can see if you remember, we needed only 378. So we have here 400, 400 watts. So it means that this inverter is suitable for our application. So what we learned from here is that we have at 150 watt inverter with that social power suitable for our load. So we have now selected are involved. Now with this inverter can be 12 or 24. So how can I selected the voltage? So if you look at here, you can see this information is really important and we talked about before when we discussed the batteries. So if you have a small installation or loads up to 1,200, what? You choose a 12-volt DC battery system, or a 24 if it is a medium, or 48 or 96 if it is a large installation. Now, if you get back here, you can see that our power is 250, or to be more specific, our load here is 1198. What? Right, so this is a continuous power of solute or the total load we have here. So you can see it is less than 1,200 watts. So this is a small installation system. So in this case, we will use at 12-volt DC voltage. So our system of batteries will operate on a 12 volt system. So we selected our system voltage of our batteries. Now, the next step is that we will size our panelists. So we saw is our inverse and at some time who selected the voltage of the battery. Now we need to size our panels. So we saw as our patterns are based on what? Based on the energy requirement per day. You can see all of this. One sounds at 90 to 1 h per day is the energy needed per day. So this energy, which is required by our load, will be taken during the day from solar panels and during the night from the batteries. So we have to design our panelists to give power during the day to our load and charge the batteries. So it gives us enough power to give non-polar for that low during the day. And the folds of batteries for charging the batteries to provide electrical power at night. So what we are going to do is that we will take this number, which you have the total energy required by the law. So it is in this site. We will take this energy and multiply it by 1.3. So we take one solves onto 92 and multiply that by 1.3, like this to get this value. Now why do we add a 1.3? This is a safety fact. It is used to accumulate for all the losses in the PV system in addition to the palace and not operating at the optimum conditions. Now, let's understand this system statement. The first thing is that you have an inverter. Inverter has an inefficiency. Controller have any inefficiency that the conversion of the petrous from electrical energy into chemical energy and from chemical to electrical. This also suffer from losses in addition to losses inside the cables itself. All of these are losses in the system. So that's the first part, the losses due to the efficiency of the system itself. And inside the keywords, in addition to in addition to the solar panels are not operating at the optimum condition. Now what I mean by this, now this solar panel, e.g. 100, what, what peak or the peak power of the panel is 100 watt. Now remember that when we look at a solar panel and see 100 watt, what does this even mean? It means that this panel can provide 100 watt at these conditions and 25 Celsius degrees. In addition to 1,000 irradiation irradiation and 1.5 air mass, if I remember correctly. So these are STC conditions or the standard test conditions. Now in reality, we may not reach the 1000s irradiation. And the temperature may be higher than 25 Celsius degrees. And the air mass is not 1.5. Or even there is an error in the tilt angle itself. All of these causes losses in the, in the PV system. In order to accumulate for all of these losses, losses due to the equipment, losses due to the angle, due to operation conditions. We are going to we are going to and add a safety factor of circumstance. We are oversize in our panel supply 30% to accumulate for all of these losses. Hope it's clear right now. So 1419, 0.6 watt hour is the one which we are going to design based on it. Now in this first example, we will select a Canada, e.g. we will assume that my own location is in Canada, not always in Egypt or my own country. So what I'm going to do is that in order to get the power required from the panels, it will be equal to total energy needed. Divided by is a Peak Sun Hours. How many hours available or some hours available in my own location. And to be more specific, the worst sun hours, the worst or the least amount of sun hours in the location I'm designing based on the worst case. So here I'm looking at this map. This map is really important to get the amount of minutes on ours. Now for any location, you can see that here, e.g. in my own country, Egypt here as this red location, you can see it is 5-5, 0.9 h or sun hours. So I'm going to choose the worst, which is 5 h. Now here's this location I selected in Canada. This specific location, not all of Canada, but this part, specifically. If you look at this part which is with this color, you can see 2-2, 0.9 h. I'm going to select this award just some hours, which is 2 h. So the energy, which is what I selected divided by number of hours, it will give us how many watts required from the panel, or how, or what is the power of the panels. Now, why did we divide by hours? You can see what our we need to divide by number of hours to get there. What required? Now, what does this mean? If our panelists have 700 undermine t as a power for 2 h only sun, it will give this amount of energy. Okay, So let's continue. So we have here our pan. Now the next step is that we are going to select the BV panel that is going to be suitable for this power. So any panel you can select, 100 watt panel, 150, 200, 300, whatever you would like. It is up to you. Okay. So here e.g. I. Selected are some power panel with a 200, what? Which is this one? And this is a monocrystalline monocrystalline BV panel. So as you can see, the number of panels will be the total power required. Divided power is a power of one panel which is 200. What? You can see it's 100 online divided by 200. You can see it will be 3.549 or approximately four panels. Now I would like to mention something which is really important. Now, we try to get to that closest even number. The closest even number nodes, the odd number closest to even number. The power of the panels that will be equal to the total power in this system. We have now four panels. Each appellant is 200 watt, so it will give us 800 what? We needed only some random line. Now we have 800 what coming from the Annals. And these are the electrical characteristics or the electrical aspects of the app PV panel is DC power rating. The canon that maximum power, maximum power point, voltage at maximum power point, short-circuit current V open circuit and more factors here. Now we will use this when we are going to select our charge controller and when we select that connection of the panel. Now zoning system is we will size our batteries. Now, how can we summarize our biters? So first, we select it in this application, we selected that lithium ion phosphate battery. Lithium ion phosphate battery. You can see it is at 120.8 volt, which is that 12-volt battery. As you remember, we said that the voltage of the battery as a floating condition is higher than the one which is available on it. So that 204-20-2012 volt is at 120.8, 24 volt is approximately more than 25 volt, and so on. So at 12.8 means it is a 12-volt battery now and it's on per hour is your hunger uncertainty? I'm per hour. Now if you look at the data sheet for this battery and you'll find this datasheet of goals inside the course itself. You will see here lithium ion phosphate, lithium ion phosphate, different types of voltage and capacity. So you can see 12.8, we're going to eat all of them are 12 volt batteries. Whether they're fronting capacity, you can see 50 ampere hour security Ampere, our hundred ampere hour, hundred and 6200300300. And search. Now, you can select again any one you would like. It is not, There's no certain guideline on selecting which a battery you can select whatever you would like. However, I selected the highest ampere hour to reduce the amount of battery is required. Now, you can see here another important things. You can see here we selected this one. And you can see nominal voltage and nominal capacity at 25 Celsius degrees surround the uncertainty and Power Hour at zero Celsius degree, you can see is that as the temperature decreases, as temperature decreases, you will find that the emperor, our start is decaying or going down. That's why the temperature correction coefficient is really important, which we have discussed when we talked about with the datasheet of the lead acid batteries or to be more subsidies that EGM battery. We said that as the temperature goes down, you will find that the ampere hour in which we can take from the battery assault is going down. Now here you can see psychic life. Depending on the episode is a charge. We said that the higher the tips of the surcharge, the lower cycles we take. You can see at 80% depth of discharge yourselves and 570% 70,050 per cent of 5,000 and so on. Now in this case, since I'm talking about lithium ion, lithium ion, phosphate, iron and phosphate, we will select 80% depth of discharge. So if you have a lead acid batteries, we will select 50 per cent depth of discharge. If we have lithium batteries and we will select the 80% depth of discharge. So here this is a specs and this one which I select it. Now how can we size up batteries? So first, which is really important that what is the lowest condition or the lowest temperature inside the location. Now since I'm talking about Canada, I will assume at when negative 20 celsius, 20 Celsius degrees, negative 20 Celsius degrees. This is a lowest temperature in this location. Now, depending on the location itself, you can define the lowest temperature. Now why is this important? Because as you can see that this battery is surrounded uncertainty and per hour, right? However, when the temperature goes down to negative 20 Celsius degrees, you can see that the power rating or the bare, our rating became 160 amps per hour instead of 130. So you can see at 25 degree, which is the one which is. Showing on the battery itself. So all the uncertainty is at 25 Celsius degrees over F. We designed based on the worst condition. So negative doin, associate's degree is 160 amps per hour. You can see we have now capacity of hundred and 60 instead of 130 ampere hour. Now, how can I convert this into something? Which way you're going to use in our design is that I'm going to make it adequate as a correction factor. So I'm going to use this as a correction factor in this housing moves up buttresses at temperature, correction factor will be the ratio between the new and better our hundred and 60 divided by the original or nominal capacity will give us 0.48. So I'm going to use only half of this battery during the worst condition. So how can we size the batteries? Now is I am bear out as a buttress will be equal to using this formula. Total energy needed, which is the energy provided by the PV panel nodes allude energy bonds a BV Bannon as our energy coming from the BV panels multiplied by days of autonomy. How many days are we good, Don't go and not to have any sense of autonomy or days at which the sun is not available, divided by depth of discharge, which is here selected as 80 per cent multiplied by the system voltage. So how are we going to select our batteries in that form of 12 volt or 24 or 48. What system voltage are we going to use? Now we said that we, based on the inverter we selected at 1 v system, since it is a very small installation system, multiplied bys S by two Budweiser temperature correction coefficient, which is 0.48. So here in Canada, I'm assuming that we have two days of autonomy today is when the sun is not available. And total energy needed, which is the energy coming from that butter as PV panels, 1419, 0.6 watt hour. For two days of photography. Today's at which the sun is not available, divided by depths of this is charged 0.8 here, 12-volt system and temperature correction coefficient, coefficient of 0.48. So this will give us the ampere hour required 616.15 and pare out. Okay, so this is ampere hour. We need our battery to provide. Now, using this, we need to see how many batteries in series and how many batteries are in better. So in order to find in series, it will be the system voltage. Divider bias is a battery voltage here we are going to have a system voltage of 12 v. This is a small system and the battery voltage is 12 volt, so we will have only one battery. You need to see here is a string. So only we have one battery in each string. Now how many parallel batteries? It will be Amber, our required divided by CM per hour of one by three, which is 330. So to give us approximately two parallel strings. So we have in Z n, how many batteries to batteries. One string multiplied by two parallel strings give us two by three. So we have two batteries like this in parallel. In better. We will see the schematic when we diagram of this system when we finish this lesson at the end of the end of this lesson. Now what important questions that you will get? I will get this question, so I will answer it before anyone asks. Why did I use the civil Homeland Security and where our N instead of Zahn, hundred and 60. Now because you already added the effect of temperature here, you can see the temperature correction coefficient. We added 0.48 to accumulate of the reduction in ampere hour. That's why when I'm going to design my own PV panel, I'm going to use the nominal value since I already take or takes the effect of the temperature inside the amber hours of battery. I already take this effect or toxic effect to be more specific. So again, if you would like to remove this one, you can remove the temperature coefficient from here completely what exists. And then the value which will be here it will be, it will be in this case, lower value, let's say e.g. through hundred ampere hour. I believe something like this. Very close to this value. So I'm going to take this 300 and per hour here, make it this 10 hundred ampere hour. And then when I take the amber, our form butter, I'm going to use this one divided by hundred and 60. So it will give us the same solution. So again, if I take the effect of temperature in the equation, then I'm going to use here the nominal voltage. If I don't take this effect, then I'm going to use the reduced battery capacity. Okay. I hope it's clear. Now. Let's see you. So you can see that the system will be like this, 12-volt parallel to add volt. It will give us 606 tampered. Or we can see parallel connection will give the same voltage, which is 12 volt. And it will lead to addition of the two values, 660 and pair. Now, next step is sizing of the charge controller. So how can I solve is my only charge controller. So we have now is as a power coming from the PV panels is 800 Watt as we designed, system voltage of the battery is 12 v. So I need a charge controller that can take an input power of 100 watt and having a system voltage of 12 volt. So here I'm going to use this one, which is a maximum power point tracking charge controller. Now, very important. Another very important note here is that when we design a PV system, we have to select a maximum power point tracking controller. Don't ever it choose. Pulse width modulation. Modulation will cause losses in the system. So we have to choose a maximum power point tracking charge controller. So let's look at the specs of this charge control. So if you look at from the vector one company, you can see here 150 slash 7,050 slash A25 and 50 slash hundred. Now what does this represent? Hundred and 50 representing what? 150 representing exam. And maximum b V open circuit voltage. Now we can see here, let's look at the aspects. You can see battery voltage, 12 or 24 to 48. You can, it is an auto select Sousa charge controlled selectors that system voltage. So if you are connecting the batteries in a 12-volt, it will operate at, at 1 v. If it's connected at, at 24 v batteries, it will operate at 24. So it is auto select. It don t need to do anything. Right at the charges, the current 70, 8,500, which is the value here. And see is this value. This has a charge or current, maximum charge currents that it will provide to the batteries. Okay. To the batteries are charged. The current going to the buttress was opposed to will go here and negative we'll get back here. When the all connected as the battery maximum of charging account of each of these charge controller. Now what I'm looking for is that number one, nominal BV power. So we selected that will revolt system. And the power which is 200, what you can see here, 1,000 watts. So it can, with stand this system. So you can see 100 watt here, 1,000, which can withstand the power of the system. And system voltage is the battery voltage is 12. What you can see the world revolt, 1,000. Okay? Now what I'm looking for is very important to information number one, maximum. You can see here maximum BV short-circuit current 50 and bear. And maximum open-circuit voltage, which is 150 absolute maximum coldest conditions. Now, I know this lesson is that very large lesson, but this is really important because we are collecting lots of information that we discussed inside the course itself. So let's see how this will affect us or sizing of our panelists. This to that maximum open-circuit voltage will affect the how many panels in series. The maximum be visual circuit current will affect how many panels in parallel. Now a very important note here is that when we select how many panels in zeros, you can see that we choose the maximum or we selected is a maximum B V open circuit voltage in order to design the maximum panels in series. Now, if we, if we have the maximum power point tracking range, voltage range, we will design based on it. However, here you can not see it. Now, let's understand this. We have other types of this one as Annas or type of a maximum power point tracking charged controller. You can see that the maximum B V open-circuit voltage, so that the panels ones, they're all connected in series. The open-circuit voltage of these panels when they are in series should not exceed 100 volt. Okay, hundred volt. Okay. Hungry involved at what condition? At the coldest temperature or the lowest temperature in their location. Because if you remember when we talked about with maximum voltage of the panel or BV string? If you don't remember this, you have to get back to this lesson. When we talk that poets a maximum B V voltage, we said that as the temperature goes down, when the voltage will keep going up, we have to make sure that at their worst conditions, at the worst condition, this voltage does not exceed a voltage of the charge controller and the open-circuit voltage as all scenes, any console slide. Now you can see also inside the charge controller itself is there is a maximum power point tracking range between two volt to voltage of the battery plus 2 v. So let's say 12 awards and it will means 24 volt to 72 volt. Now, if we have this range for that vector on the controls, and I'm going to design based on this range, okay, based on the range of 24 to 72. You will see this when we talk about the hybrid system. In the hybrid system, you will find that I am going to design based on this range. However, since I don't have this range in that charge controller, if you get back here, you can see I don't have here the maximum power point drank range. I'm going to design based on the maximum open-circuit. Okay? So here is a series panel is dependent on the maximum power. This is a default seen. The default design is that I look to the maximum power point tracking range, and I try to make the panel voltage at the middle of this range. So I select, I connect all of these panel to have a voltage of the voltage of that range. Here you can see 722472. So I would like to make this balanced connected to an amount of about 50 v in the middle of this range. However, since I don't have in this example, I don't have the maximum power point tracking range. I will take a half of the open circuit voltage because I would like to be, I don't want the voltage to be very low because that shows you control may not operate. And I don't want it to be very high. So to prevent these are over voltage on the charge controller. That's why I select the middle value or the hub of the open-circuit voltage. So here, this will lead us to the panel connection. So the panel connection, as you can see, is based on what? Based on the charge controller. So you can, you can design the panels, then design the connection zone and designs or charge controller. But I don't prefer this. I prefer selecting a charger controller. Then based on the charge controller, I will connect my own panels. So here I'm going to first start with the voltage. How many panels in series? So I'm going to choose that hundred and 50 v as my own reference. Absolute maximum cold condition, which is worst or the lowest maximum open-circuit voltage. So assuming is a selection of the open-circuit voltage at the middle of the maximum V, V open circuit voltage. So I will take 150, divided it by two. It will give us 75 v. Now we have 75 volt, right? Okay, which is a value that I'm going to design based on it, which is the open circuit voltage. So let's look at the open-circuit voltage here. So panel itself, V open circuit is 47.8. So I'm going to design based on it. Susan, number of panels in series will be the design open-circuit voltage divided by the panel open circuit voltage. So it will be 75/47, 0.8 equal to 1.57, or approximately two panels in series. Okay? So two panels multiply by 47 gives us a value greater than 75. Now how many panels in parallel it will be total number of panels which we have designed before in the panel itself. In the beginning of this lesson, we said we have four panels. We will divide by number of panels in series. It will give us two parallel strings. We have two panels in zeros, okay? Parallel to another two panels like this. So two panels in series with two buttons in zeros as these two are parallel to this job. Now, what are we going to do next? So we selected the number of panels in series, 47. Helpful Notes Regarding Example 1: Everyone. In this lesson, we will have some help off notes regarding the first example on design of the grid system. You have to remember that when we size the maximum PowerPoint tracking charge controller, we have to make sure that the charging current, which is the bt current reading of the charge controller must be sufficient to prevent any current or any power losses oc carrying. We have to make sure that the count coming out of the charge controller, must be sufficient to prevent any power losses. Now let's understand this. First, in the first example, we have the power of the panels, which was 800 t, and system voltage is 12 volt. If we look like this, if we remember the system, We have here like this, and we have here our batteries. We have here our batteries, our batteries. We have here our charge controller, the maximum power point tracking charge controller. And here we have the power coming from the panels. Here B V. The BV panels providing power this BV panels is 801. Now, what we would like to do is that we would like to know the current going to the batteries at the peak value. We would like to know the current going to the batteries, current going to the battery or the charging current going to the batteries during this condition at the 800 watt, which is the peak power. In order to find this current, it will be simply equal to the power divided by voltage. The power here is equal to the power coming from the panel, 800 watts and voltage will be equal to 12 volt. It will be like this. 800/12 gives us 67 mpiirs. As you see here. This amount of current coming out from the charger controller at the peak some hours or at the maximum power condition for the panels. Now, I have to make sure that my own maximum power point tracking controller can provide this amount of current. How can I know this? If you look at the charger controller that we selected, we selected this charger controller, the first one, this one here. And we selected the one with 12 volt and 1,000 sat. This one, if you look carefully here in this configuration or this apex or specification four as a charge controller, you will see that the rated charge current. What does this mean? This is a maximum current that is going to the batteries. The maximum current that can be provided by the charge controller. As you can see the rating is 70 apairs, this is a maximum current that it can give. And we need only 67. Here, as you can see, the rating is equal to 70 empire which is sufficient for the system. What will happen if the system requires, let's say 80 ampires. Let's say that the power is much much greater than 800 watt, and the current is, let's say 80 pairs. In this case, the difference 80-70 is a little bit bigger. We will go to the charge control. We will select this one with, for example, this one, 1,200 and wat. 1,200 watt. Now let's see what will happen in this case. We have maximum charging current of 60 7:00 A.M. Pair going to our batteries. Let's see if our batteries can withstand the current. If you remember the configuration here, we have two batteries in parallel. Two batteries in par. T batteries in parle, so we will take the current and val it by two. Each branch here. We'll take only 33.5, which is 67, which is the current coming from the charge controller. It will be divided to one going into this battery and the other current going here. This two currents, each one is 33.5 amperes. Now, is our battery can withstand, each battery can withstand 3.5 pairs. Let's go to the data sheet. This is a datasheet for the battery. You will have it in the course of files. If you see here that maximum charge current and recommended charge current. Maximum charge current, this is a maximum current that can be provided to one battery. This is a recommended charge to increase the lifetime of the battery. Now, which one did we choose? We chose the 330 and per hour, this one, 330 and per hour. This one, 12.8, which is 12 volt, and 330 330 and per hour. Now, if we go down here like this, you will see that the maximum echoge current is 400 and pairs, and the recommended less than 150. You can see 33.5, which is less than 150, which is in the recommended range. It means our battery can withstand this maximum power or this maximum current. The first part here is another thing that we take into consideration when we design the BV system. 48. Example 2 on Design an Off-Grid PV System: Hi and welcome everyone to this lesson in our course for solar energy. In this lesson, we will learn how to design an off-grid PV system. Okay, So let's start. So what are the steps of the design of an off-grid system? So as you can see in this image here, you will find we have solar panels. We have the charge controller, we have the inverter, and we have batteries. These are the components that you would like to size in our PV system. So the first step is that we are going to define our loads, are loads inside our house or what we are going to provide electrical power. Number two, we will then start sizing the inverter. Then we will size our solar panels. Then we will select our batteries, and we will select also the charge controller. And then we will have the panel connection, that connection of that panels based on the design of the charge controller. Now the first step is that we are going to define our loads. What I mean by this is that we will look at our house and see what are the different devices that we have. We have LED, we have TV, We have fun refrigerator, laptop, washing machines, and so on. We have number of devices, LED, e.g. we have four LAD, one TV to fans and so on. Then we will see how much power does this device consume? How many, what a 10-watt, 100 watt, and so on. Then we will see also the number of hours which we are going to use each of these devices. As an example, TV, we are going to use it for 10 h. Now is there an x that we will get all that energy, what hour, which is energy consumed by each of these device? Now the first thing you can see here is that the power device, where can we find this value? You will find it on that label of that device itself as the LED TV. And so now we have here e.g. you can see we have LAD, LAD, right? Each one is turn what? So the total wattage is four multiplied by ten, which means for seawater. Here TV one multiplied by 100, which is 100. And so on. Now, after getting this total wattage consume the way all of these device, at the same time. You will add all of these devices or all of these wattage to get the total wattage consumed by these devices. Now, you can see number of hours a year. After this, you will get for what, which is what consumed by that device and multiplied by number of hours to get what our, or the energy consumed. So we get energy consumed by each of these devices by multiplying hours. The blood pressure is that wattage of the device. Then we will add all of these energy together to get the total amount of energy required per day. How many what our required bear day. This is important because we will need this when we design or select our PV panels. So we have the total voltage phasor devices, and then we have the total energy consumed in one day. Now, the next step is that sizing is a inverter based on that wattage of our device. So we have 860 watt. Now how can we select the inverter which converts the DC power coming from as a potteries into AC power required for our house or our loads. So simply the inverse of power should be designed or she'd be selected greater than the total load wattage Pi 25% or a 70%. As a safety fact, we take that 860 and multiply it by 1.25 or 1.3 as you would like. Now, why do we do this? This is a safety factor for many purposes, including e.g. if you have any future loads, if you'd like to expand your own loads in the future or add more loads in the future as, as the inverter can withstand this future loads. So simply we will take 1.3 and multiply it by it was a total wattage of our devices. So it'll give us 1118 once. This is known as the continuous inverter power, that are powers that the inverter will provide continuously. Now, there is a very important term inside the inverters or in our home, which is known as that peak power or the surge of power. Now what I mean by this, now, there are some loads, e.g. such as motors, compressors, refrigerators, pumps, washing machines. All of these have a starting starting current or starting power. So we have to make sure that our inverter was a solar inverter, can withstand this starting period, which it can be few seconds to a couple of minutes. So this will lead to something which is called surge of power. So we need to identify the social power of each or the starting power of these devices. We have here e.g. refrigerator and washing machines, this to have a starting current. So what are zeros starting current or the starting power? Now, you have to go to the refrigerator and look at that. Look the router, the router current in order to get the starting power. Similar to that washing machine or users look at the surge of power. Now, let's say that you couldn't find these values. What are we going to do? You can just assume that the surge of power is three times or four times the wattage of these devices. So as an example, we can say is that the starting power of that refrigerator is four times 300 watt, or three times a 300 watt washing machines. That same idea four times or three times. In my case, I would like to be in the safe side. And I always choose the higher value, which is four times the inverter searchable. Now, let's assume that all of these device that you see here, it started at the same time, that LED TV, fan, refrigerator. All of this started at the same time. So if we start at the same time that LED plus tv, power plus fan. However, for is that refrigerator end for laptop, for that washing machine. When you multiply power by four times. So as you can see here, as you can see here, represent multiplied by four washing machines, multiplied by four times. Then if we add all of this, you will have 2,761. So here we have two values. They avert a continuous power, continuous power on thousand 118 watts, which is a continuous power, and 2760 watts, which is a sociable. We need an inverter with this value, continuous power and social power of 2,760. As you can see here. Now, we go to the market and social for one involved as I can with the standardized values. So we have this power in voter. You can see it is rated at 1,500. So as you can see, it can with stand this value that 1118. And as a social power or the peak power, you can see here it is 3,000 what this inverter is suitable for our application. Now, one important thing when you select that inverter is that you have to make sure that this inverter, inverter must be a pure sine wave. Not all modified sinewave modified is bad for it is cheap, but it is bad for your own equipment or device inside the house. So when we are selecting our inverter, when we are looking for is a pure sine wave, solar power inverters. So here we have a pure sine wave, $1,500 an hour or something, which is also important. You have to look at the voltage of the inverter. You can see here it is at 24 volt DC. What does this mean? 24 volt him means that that input dc voltage, input D, C voltage coming from the batteries is 24 volt. So this will help us to select that connection of the batteries or the system voltage. So this value held us is that we now understand that our batteries must be connected in the 24 volt configuration. Now, step number three, we need to size our panels. Now, how can we size our panels? Number one, we have the total energy. Now remember, this is the total energy that is consumed by all of our device in one day. Okay, So this is the energies that will go to the load. Now we have to understand that there are losses occurring inside our system. Losses inside cables, losses inside the charge controller is the batteries as the inverter. Cables. Also, our panels are operating at non optimum conditions. And what I mean by this is they are not operating at the STC conditions. They can be operating at any other value, which means that the power coming from it is not the peak value. What can I do? In this case? I'm going to assume as so 2% safety factor to accumulate for all of these losses are carrying is a system will take this value and multiply it by 1.3 to accumulate for all of the losses are carrying the system. So the total energy will not be this value, but it will become this value. Okay, so after getting this, what are we going to do? The next step we obtain the heel. What our now what I need is how many? What I need from the panels. So I need wattage. So as you can see what our and do we need, what we will divide here by hours. Now what ours, specifically, our switch we are talking about is that Peak Sun Hours, or to be more specific towards their beaks on ours. This are the worst as a mount or the lowest sun hours that will be available through out the year. So this is the lowest hours that we can take from our Sun. So if you look at this map, you'll find here. Here I'm talking about my own country, which is Egypt, here in this location. So if you look at here, you will find that that beaks on ours is in the range of 5-5, 0.95 to 5.9. Now, here when we are talking about powers the sun hours, you are talking about the worst-case, which is 5 h. So I'm going to choose for my own location as a worst value, which is 5 h. So the total power or quality from savannas will be the energy divided by 5 h, which will give us 1,669. So what does this mean if the sun is available for 5 h and we have panels that generate this amount of power. We will get our energy required because this is a worst-case throughout the year. Okay, So what does the next step? So we have now is a power that we need from Savannah. So we need a panel that will be able to provide this amount of power. Of course, there is no panel that will give this much amount of power. So what are we going to do? We are going to select a panel such as e.g. LG monocrystalline. This one is an LG monocrystalline. Monocrystalline, LG 300s. What does through 100 mean? Means it is through hundred words. This monocrystalline is 300. What panel? So you will get number of panels is that we need, we will take the total amount of power and divide it by the power of one. So this will be divided by each also, it will give us 5.5. Or approximately we look for the higher value, which is six. Now we have here six panels that we need and our PV system. Now we didn't decide yet if we are going to connect them in series, or we're going to connect into them in parallel. Or we're going to combine these two together. We will learn how to do this after getting is a charge controller. So the total power now it will be 60 multiplied by 300. You can see six multiplied by surrounded, which is 1801. So it is higher than that required the value. Now, this is important when selecting the charge controller. You can see here is this is an electrical properties of that solar panels. That voltage at maximum power as that current at maximum power, open-circuit voltage, short-circuit efficiency, and so on. Now we will use some of these values when we design in Zeneca slides. Now for now, we're not going to talk about that connection. We're going to go to the batteries first. Now, how can we size our batteries? Now, batteries have several functions. Is that the store electrical power during the day and provides electrical power during the night. Another function is that this battery should be designed to provide electrical power during the days of autonomy when the sun is not available. So in this example, I'm going to use an AGM at 12-volt. Egm battery is gm 12 0 volt and its capacity is 205 ampere hour with a C rating of 20 h. Now so as the capacity here, 205 ampere hour, and that will vote. Okay. So how can I get the embedding our required from the batteries? So it will be equal to the total energy needed. And what I mean by total energy, total energy that is going to be taken from the panels itself. Remember that we took the energy from solute and multiply it by a safety factor of 1.3. This energy will be the total energy needed. Then we multiply it by days of autonomy. What I mean by days of autonomy, days at which the sun will not be available. The more days we add more batteries that will be needed, or we will double the cost of our system of autonomy, e.g. if you say e.g. days in Europe, e.g. they choose 3-4 days of autonomy in which the sun is not available. However, in my own country, e.g. one day is enough. So I choose one day of autonomy and total energy needed. Now another thing here we divide by depth of discharge, because as we know when we discussed depth of discharge in the course, we said that the depth of discharge, it means how much it can I take from the battery without damaging it? Now we said before that the lead acid batteries, such as ECM Gel batteries, lead assets are flooded. Lead acid batteries, all of them have a 50 per cent depth of discharge. Then we have the system voltage. Now, where did we get the system voltage when we select as a inverter? If you remember, we said that the inverter is 24 voltages heat accept this 24 volt DC. Another thing which is that in virtual correction coefficient. What I mean by this is that this battery, if it is in a lower temperature, Zan is DC condition. You will need to, you will take less energy from it. So if you look at this graph here, which is found in the datasheet. And remember inside of the course, we talked about the datasheet of this battery EGM 12 volt 205. And we talked about this figure. So as you can see, at 25 Celsius degree or not 25 greater than 25. So Z, I don't remember exactly here. Here. Let's just leaves us. You can see at here, 20, here at 25. So if you go here, it is approximately equal to hundred per cent, which is 25 Celsius degree. Now, if you are operating at any other temperature or that lowest temperature in that location. So let's say e.g. for my own country, I will select that the lowest temperature is 20 Celsius degrees. I will assume this. So it means that that factor here or the correction factor is 90%. Now what does this mean? It means I cannot take more than 90% of the available capacity. So you have dips of discharge and you have 90% of it, 90% of the available capacity. I'm going to add this 90% here in the equation to oversize my own batteries. To compensate for the temperature, temperature, decrease in temperature, and to compensate for the depth of discharge. So as you can see here, we have the energy one day of autonomy, 0.29, which is that temperature correction coefficient. After I assumed lowest temperature of 20 Celsius degrees 24 volt, which is voltage selected by the inverter depth of discharge, which is 0.5. This will give us finally 772 and bear out. So this is the amount of ampere hour I need from the batteries. Now, how can I know how many batteries in series? How many batches in battle? This is really easy. All you have to do is the forcing is that number of series batteries will be equal to the system voltage is that 24 divided by the voltage of one battery, as you can see as this is a 12-volt battery. So in order to form my 24 volt system voltage, we need two batteries in series with each other. This is one string. Now you have to see is that 205 and bears this is that they're hour or current or ampere hour, the capacity coming from each barrel, line or parallel string. So in order to find how many parallel strings we will take the and bear our required, which is 772 here, and divide it by that impair our form butter, which is 205, which will give us approximately four per string. So we have 1234 forbearance strings. In each string we have two batteries in series. Don't worry, we will see this in the next two slides. Okay? So as you can see for purse strings, they are summation will give us the embed, our required and the series connection gives us a 24 volt. So as you can see, total buttress will be two batteries in series multiplied by four branches will give us aid. Batteries. Now let's see that connection, as you can see here, is a battery 12 volt, 12 volt. They are connected in series, in series, in series and series. So for parallel strings to a two in each string, two batteries in series. And finally, we'll take the negative terminal and the positive terminal for our factory can see finally, we will get 24 volt, which is a series connection. And it hundred and 20 and bear, which is the summation of this hour. You can see 1234. So if you take four and multiply it by 205/h, you will get the 820 ampere out. So this is the sizing of our batteries based on our system. Okay, Now, next step sizing is a charge controller. So what do we know till now is that we have power of the panels itself is a peak power of the panels is 1,100 watt, and the voltage of the system is 24 volt. I'm going to search for a charge controller that has maximum, or at least it can with stand 1.8 kilowatt from the BV systems or the BB panels, and at least can have a voltage of 24. So what are we going to do? I'm going to search for that vector on company victim is one of the most widely used and most widely known brands in the world for a charge controllers. So here I'm going to choose a maximum power point tracking. And of course, you have to choose a maximum power point tracking because it will start getting that maximum power from the panels. However, pulse width modulation, it is cheap and it will lose lots, lots of amount of electrical power. So don't use bold Swedes and modulation. Always look forward to that maximum power point tracking. Now we selected this 150 slash hundred. Now let's look at this specs. Now, as you can see here is that maximum power trains, which to look at this one, this one. Now why is this one you will see right now, forest is that I'm looking for and system voltage is 24, okay? So this is a line nominal BV power 24 volt. Okay? Now we have different options that we can select this one, or this one, or this one, which one should I select? Now, this will be based on the BV power. You can see nominal BV pour at a 24 volt is 2000 watts. So it can with stand input power coming from the PV panel up to two cells. And one. Here we can see the power of panels is 1801. So this one can withstand the amount of power in our system. So I'm going to select this one. This is the image of 400.5000 or slash hundred. However, we are selecting this one. Okay? Now there are other types which have a higher current rating and the higher power for the same application. Now what I'm looking for is another two important parameters which will help us in designing or forming our panels in series and parallel. The first thing is the maximum short-circuit current, which is here, in this case 50 amperes. And the maximum B V open circuit voltage, which is 150 volt, adds the absolute maximum coldest conditions. We have this value and this 150 amps and 150 volt, which is the absolute or the worst, or the highest voltage, highest open-circuit. This is the values at which is this charge controller can withstand based on these values. And you're looking at those aspects of our battery or our panel. It will help us to select as a panelist in series. And now we will start with the maximum B V open circuit voltage. Now, since we don't have the range of the maximum power point tracking, we will use this 150 v. Okay, and how can we use this simply, you are going to assume a middle value. What I mean by this, you don't see design based on the highest worst case design with the middle value. So we will select as the open circuit voltage at the middle of the maximum BB or half of this value. So we will select that we are going to design. Or form is a series connection based on half of the worst value, which is 150/2, which is 75 v. Now, using this value, we will know how many panels that we need in series. So we will see the open-circuit voltage design value which results to selected. You can select any value. But I would like to select a value not very close towards the 150 and not very low. It is value in that metal. So as you can see here, 75 volt divide the pie is a panel open circuit voltage. Now if you look here, open-circuit voltage, so 38.9, so we will divide them by each other. So it will give us, give us approximately two panels in series. So Pi, connecting two panels in series, you will get the voltage required. Okay, which is close to 75 or a little bit high. Now, how can we know how many panels in parallel symbol you will get total number of panels and divide by number of panels in theaters. Now remember, we said before that we have a 300 what panel? And we are going to select the six panels. Okay? Now we already know now that the number of panels in series is two panels. So the remaining is that we divide six by two to get three per strings. So we have three strings. In each string, we have 22 panels in CS. Okay? Now the next step is that we have to make sure that this design is good for this charge controller. Now, what are we going to do? First, we will look at the open-circuit voltage at the worst case in our location. Now, how it will be, it will be number of series penance, number of series panels, which is two panels in series, multiplied by open-circuit voltage of one panel, which is 38.29 from that data sheet. Okay, multiplied by an additional part, which is temperature compensation coefficient. Now is the temperature compensation coefficient. It will help us to ink, change or modify our open circuit voltage based on the operating temperature. So here, I have said before that the worst temperature in my obligation is 20 Celsius degree. Okay? Now, twin Celsius degree is equivalent to act temperature compensation factor of 1.02. I'm going to show you that table in the next slide. So by multiplying this value by 1.02, you will get 79.3, which is lower than the absolute maximum coldest conditions. Now second thing we would like to do is that the short-circuit current we have to make that shows that the maximum BV short-circuit current, 50 amperes, our design does not exceed this value. So in our design, what we do is that we look at the worst-case, which is the input current of the charge controller, will be equal to short-circuit of one panel, which is ten and bears multiplied by number of parallel strings because Morris parallel strings more correct. So in this case there will be three barrels strings multiplied by a safety factor 1.25 or 1.3. Now why is this? Because the temperature itself affect the performance of that charge controller. We have to give a little bit space for it. So if I do this, I have 1.25 as safety factor multiplied by three per strings, multiplied by ten. I bet it will give us this value which is lower than that short-circuit current. Now, there are two important and notes and I would like to say before we go to the next slide. Now you can see here in that table of the charge controller here, you can see at a charge voltage absorption, charge voltage afloat. Now these two values, you can see we have a default settings and you can change them. Now, these settings, if you are a member, they are found in the datasheet of the battery itself. So according to the type of battery and according to the voltage values, you will need to adjust them inside. Their charge. Insides are charged controller settings itself. Now if you don't know about absorption and the float values, you have to go back to our lesson for the lead acid cycle and lithium ion psych. Now, let's see is that the ritual compensation factor. You can see some virtual compensation factor here called correction factor. You can see here depending on what range you are operating in Fahrenheit or Celsius, you are going to select what factors. So the lower the temperature, the higher the factor, which means more voltage will be reduced. Now finally, after connecting our system forming everything, we have all of our components. So we have two springs in series, two panels in series forming one a string, another two in series, another two zeros. So we have three barrels strings. Now we have that red. The red MC4 or the red cable representing is up all stiff and the negative representing the black. All of this will go to the combiner box in which we have two plus bars that will collect all of the post stuff together and all of the negative together. Then we will take the positive and negative and we will connect them to the maximum power point tracking charge controller. Now if we look carefully here, here you can see and the charge controller we have here, the positive and the negative of the panels. Now you can see on the charge controller, you can see BV, false negative. So we will take this up all stiff, which is a red one connected here and negative connected here. Then we have the output of the charge control just going into the battery. It will be like this. The negative will go to zoning, buttery and the post of two suppose doubles. So as you can see here, as you can see, now, these two are going to charge as the charge controller, the charge, the batteries. Now from we will take also another positive terminal and Amazon negative terminal and connect it to our inverter to provide AC power to our loops. So I hope this lesson was helpful for you in understanding about the design of the off-grid. 49. Helpful Notes Regarding Example 2: Hey, everyone. In this sloson, we will have a helper for notes regarding the second example on the design of the of grid systems. Again, the same condition when we sign the maximum pop point tracking, we have to make sure that the charging current rating, which is a current going out of the battery, going out of the charge controller must be sufficient to charge the batteries and prevent any power losses. In this example, we had the power of the panels equal to 1,800 t, and System voltage is 24 volt. Let's see the maximum charging current. It will be the power of the panels divided by the voltage, similar as we did before. The maximum charging current is 75 amperes. Now let's look here. Here in this example, we used the same me of the control or this one. It's nominal BV power, 12002, this one. Here, we selected this one. 24 volt and 2001. What is the value of the charging current? The maximum charging current is 70 amperes. This is a maximum current that this charge controller can provide. Now, as you can see, this is 70 ampirs and here 75. Instead of 24 volt, multiplied by 75, which will give us 1,800, what? This is the power coming from the pennants. In this case, if I use this one, it will be 24 multiplied by 70 s. 70 s instead of 75 mers, it will be than this value. You can see that the difference between the two, which is five pairs will cause some power losses in the system. If you look at the ratio between five pairs and 75, it will be approximately 6.66%. You lost 6% from the power coming from the panels. Why? Because used charge controller with a lower reading than the maximum current. What will happen if I use this one? I I use this one, the maximum current, that it will give 70 pairs, and the difference will be clipped. The power will be clipped, you will not have the maximum power. We have two options here. The first option is that you will allow the five pair to be clipped, and in this case, you will have approximately, let's delete all of this. You will have approximately 6% losses in the system. This is the first option. Second option is that you upgrade to the 85 per rating. You can see here, 70 per. This is the next rating, 85 per 24 volt, and than 400 this one. However, it will increase the cost of the system. If you don't like any kind of losses, you can select this one. If you are accepting 60% losses and consider this 60% as a part of the 30% over sizing of the system, then it is okay to use this one. Now, let's see the batteries in this case. We said that our batteries in this design is consisting of four branches, four parle branches. In this case, if we selected the 70 pair maximum per point tracking, it will give us a maximum of 70 pairs. 70 pairs, maximum current, coming from the charge controller. It will be divided to one, two, three, and four. It will be 70/4, each branch will or each group of batteries will take 17.5. Remember, these two are in series. The current of flowing through this battery is similar to the current flowing here. 17.5 amperes. Now, let's get back to that data datasheet of this battery, maximum charge count is 20% of C 20, and we'll learn that 20% of C 20, C 20 here in this battery is 205 p r, 205 r So 20% of this value is equal to 41 p. Each battery can withstand 41 per, which is much greater than the required or maximum current, which is 17.5. I hope this clarify or give you more clarification or you observe now more a it or understand more the design of grid systems. 50. Overcurrent Protection Guide: Hi, and welcome, everyone. In this lesson, we will to pot the Over current Protection Guide for BV systems. We will learn in this lesson, how can we select circuit breakers or fuses in addition to the cables inside the BV system. Let's start. If we look at a BV system here like this one. This one is a big BV system consisting of a group of strings. These strings will form sub arrays. If you look at here, you can see one string, as you can see here, this is one string with a positive and negative terminal, as you can see here. This is another one here. With a positive and negative terminals, another one and another one. These strings are combined together using something which we call a string combiner box. What is the function of this component here? Its function is to combine all of the strings into two terminals, positive and negative. Now, as you can see in this figure, you can see the small rectangles here, red rectangle, plaque. What is this? This representing the protective fuse for protection of the string and cables. Okay. Now, what will happen here if you have a very large BV system, very big BV system. We have this group of strings form is an array, and this group of strings form is another array. Now, when we have multiple arrays in one BV system, we call them sub arrays. We have this one, the first one here, is called sub array sub array, one. Let's say, for example, this one sub array, number two. If we have another one, sub array, number three, and so on. When we take all of these, you can see here positive and negative, positive and negative, and we combine them using something which we call sub array combiner pox. What does this mean? It combines the sub arrays. Similar to this one here, which is called string comp pox. It compines group of strings. This one come group of sub arrays and forms final two terminals, give us the two terminals of the array. As you can see this array has also a protection device called array fuse link. Now, the first question here, number one, do we need fuses in the positive and negative terminals, or it is enough to add post fuse on the positive or a breaker on the positive terminal? According to the cooper pus men, cooper pus men is a company for protective devices related to BV systems. They provide BV fuses. According to them, you need uses in the positive terminal and negative terminal. However, most likely or most of the BV installation, Companies use fuses in the postive terminal only. Now, second question, do we need to add fuses in every BV system? Do we need fuses or a protection device? In every BV system? The answer is, no, you don't need fuses all the time. We will learn when we need exactly in the next slide. As you look here at this system, you can see that we have here, number one, which is a fuses, you can see here, photo voltaic fuse lengths or BV fuses. This one is a fuse holder that holds this fuse, and we have another type, which we will see in another lesson called the inline fuse holder. This one, as you remember, the two terminals of the BV panels are MC four connection, right, MC four terminals. This MC four can have something which is called in line fuse holder. We can add to them inside them F fuse. We have also inside the combiner box surge protective device, which is used to protect against lightening arrests or lighting light lightening surges. If you look at the restor system, we have also uses or circuit breakers. Let's start by questioning ourself. Do we need over current protection for each BV string all the time. Actually, no, when do we need Protection or over current protection. First, if you have one single series string, just one string. If you have a BV system like this one here, just one string going to a charge controller. One string here with positive and negative terminal, going to the charge controller. If you have one single string according to Article 690.9 in the NEC NEC or the national electrical code, you don't you don't need any e. You don't need any views. You don't need to add a protection for this type for one single series string. However, there are some conditions. The first condition is that This string should not be connected in parel with other sources. We there is no external sources connected, such as a connected source circuits, batteries or any pack feed from inverters. In this case, you don't need fusing. Number two, this this sable here, which is a two terminal, going to the charge controller, be sized at 1.56 multiply by the short circuit current of the BV panel. If you look at the BV panel here, This PV panel on the datasheet or the specs, it has a certain short circuit. When we size our able, it must be 1.1 0.56, multiplied by a short circuit. This is a minimum value, minimum value. Let's understand y 1.56. 1.56 is divided into two parties. It is 1.56, it is 1.25, multiplied by another 1.25. What is the first one? Here, what is the worst current that can go out of the panel? What is the worst, the worst current is a short circuit. Now, you have to understand that the shot circuit on the panel is at condition of irradiance, 1,000 wat perimeter square. Now, let's say for example, in any time of the day, let's say at noon, for example, the thousand one perimeter square goes to 1,200 what perimeter square, for example, As radiance increase, the total current going out of the panel will also increase. It means that the short circuit will also increase. We have to account as a safety factor for the presence of over radiance condition. In this case, we add 1.25 as an over radiance efficient as a safety factor to accumulate for any increase in current due to the increase in the radiance. Number two, second factor 1.25, it's called the derating factor or known as three hour NEC. What does this even mean? The N NEC or national electrical code say that or states that if you have, for example, a cable or a breaker or a fe or any element or any electrical element, in which current will go through it more than 3 hours continuously. If, for example, if you look at the BV system here, of course, the current will go through this cable more than 3 hours continuously. That's why you have to derate our cable by 80%. For example, if we select a cable of 100 pair, and we know that current will go through it more than 3 hours continuously. We have to only load our cable by just 80 pairs. Loaded it by 80% only. Why? Because this current when it goes through the cable, it will cause heat energy and increase the temperature of the cable. That's why we need to unload or decrease the loading on this cable. So if you have 100 pairs, you have to go down to 80 pairs only. In order to choose a cable, we need to multiply by 1.25 in order to accumulate for d rating by 80%. I know you don't understand. Let's say for example, that our current is 100 pairs. We need this cable to be loaded by 100 pair at full loot. What I'm going to do is that I'm going to take 100 B require and the multiply it by 1.25. We will choose a cable of 125 pairs. Then when we apply the d rating by the NC three hour NS. When we multiply this by 80% to lot this cable by just 80%, we will get the 100 and pairs required. We oversize or choose a higher cable, at which when we decrease its rating or date it by 80%, we will get the required de current that we need. I hope it's clear. So we have 1.25 multiplied by another 1.25, which will give us 1.56. So derating factor again for the three hour NEC when we have a current going through a breaker or a fuse or a cable for more than 3 hours. That's why we add this derating factor of the NEC international NEC cod, and 1.25 to acumulate for any over radians that will lead to increase in current. Okay? Now, another thing that you will find these rules that I'm talking up in this slide, similar in the IEC code. In the IEC, you will find it is similar to the NEC. Same rules. If you have a single string, you don't add any fuse. Okay. Now what if I have two strings in parallel? We have one and two. Let's say we have two strings, here, post negative. We have two strings like this. Take this one here and this one here, this one here, and this one here. Here positive, negative, positive and negative. This is the first string and this one is the second. If we have two strings in parael, you don't also need any fuse. We don't need fee in the single series string and we don't need any fuse in the two parallel strings. This is according to the NEC and EC. Here it says that the fusing is not required if the salt circuit from the current does not exceed the ampacity of the conductors or the maximum of a current protective device size fight on the PV module name plate. What does this even mean? As you can see, we have two parallel strings. Now, let's say for example, that here, Here, our panels. Let's say, for example, a short circuit occurred here, short circuit. What will happen here? This panel will not provide any current. However, this panel will start supplying electrical current that will go as to the short circuit location. What is the maximum current that will go from here to here? The maximum current will be 1.25, which is the over radiance coefficient, multiplied by short circuit. This is a maximum current that can go from here to here. As you remember that we said that we select the sable as 1.56, 1.56 multiplied by i short circuit. This sable can withstand this short circuit current. The cable here can withstand 1.25 multiplied by i short circuit because it is 1.56 multiplied by i short circuit. This is the first condition. Second condition is that this panel On the specs, it has a maximum of c to protective device size on the specks of the panel. Let's say, for example, 15 pairs. It means that the maximum few that I can add or maximum current that the panel can with the stand is 15 pairs. If 1.25, Multi short circuit less than 15 pairs, then it is fine and you don't need any fe. We will see this in the next slide. As you can see, each string will give us a maximum current of 1.25 Mt blood by shot circuit, and our cable is 1.56 or higher. The combined circuit fold cart is not large enough to cause any damage to cables or modules. That's why fusing will not be required or we don't need any fusing in this case. Now, let's understand what I'm talking about. We have here the short se current that we use, and you can see here the maximum series fuse rating, which is 15 pair. What does this represent? This representing this part? You can see here maximum of current protective device subfi on the PV module name plate. You can see 15 pair. If we have two string perel. If the current, which is 1.25 worst short circuit count, 1.25 multiplied pi, 8.87 will be, of course, less than 15 empirs. You don't have to worry about any thing. Similar to here, another panel that we used in our design, I short circuit, and ses fuse rating. 15 empir. This is a maximum fuse that can be installed, Now, when do we need over counter protection? Starting from three strings or more in parel, according to the NEC, we need fusing. Why? Because you will find that in this scenario, if you look at here, we have one string two, n three. This one will give us maximum short circuit current of 1.25, multiplied pi, short circuit. This one will give us a maximum current of 1.25 multiplied pi, short circuit. Let's say, for example, we are talking about this sable or this panel has a fault inside a short circuit. We will get a current coming from this string to here and a current coming from the other string here. What is a short circuit current? It will be 1.25, multiplied by short circuit, plus 1.25, multiplied by y short circuit, which is 2.5 multiplied by short circuit. If you remember that our conductor here is sized as 1.56 multiplied by short circuit. As you can see that the short ct is higher than the ampacity or the capability of the cable. Higher than the pair the cable can with a stand. That's why we need a f to be added here to protect the cable against short circuit. That's why starting from three or more, we start needing a fused to protect or a breaker as you would like. You can see the combined current, as you can see here, is higher than the size, which is 1.56, as well as, of course, a series fuse rating of the PV modules. Under this fault condition, the conductor and Bv modules will be subjected to damage because here, for example, let's say these two currents, let's say 16 pairs. This one has a maximum fuse rating of 15 pairs. In this case, the modules will be damaged or B pernit. That's why we need a fuse to protect both of the modules and the cables. Let's have a summary for what we just have said or explained in the previous slides. If we have a string here, as you can see here, number one, if a VW system has three or more strings connected in parall, we need to have each string protected. We need a e for each string. Number two. If the system has less than three strings, it will not generate enough fault current to damage the conductors equipment or modules. Number three, if we have three or more strings in peril, a fuse link will protect the conductors and modules from over C fult of course, this will isolate the fold string. The rest of the BV system can continue to generate electricity. L et's say, for example, if we have a short circuit here in this group of panels here. When the current will go from here through this fuse and the current will go here through this fuse, and the current will go here through this fuse. What will happen exactly is that this fuse will pre, it will be permit and prek and it will isolate this part from the rest of the BV system. The rest of the system, this string, and this one and this one will continue to provide electrical power to the system. Now the last thing I would like to mention is that again, you don't have to add fuses in the postive and negative terminals. It is enough to add in the postive terminal of the PV panels. The post and negative is recommended by cooper, us men company, which you provided fuses for and the BV Ptction devices for a BV system. 51. Example on String and Array Protection: Hey, everyone. In this slason, we will have an example on string and array protection. We will learn how can we apply the previous rules that we learned about NEC standard to protect BV systems. L et's again understand why do we add fuses in the case of more than three elements. Let's look at the circuit here. You can see we have how many strings, one, two, three, four. We have four parle strings. Now, let's say for example, we have a fult occurring here in this panel. If we have a fult here, what will happen? There will be a current coming from this string. Like this, going to the fault location, and this one will also provide electrical current, and this one will also provide another electrical current. As you can see how many strings that will feed this fault, one, two, three. We have three strings that will provide current. What is a total fult current, it will be three. Multiplied by the maximum current coming from each panel, which is 1.25, the over radians coefficient, multiplied by the i short circuit. As you can see here. Now, in general, as you can see here, we have already four strings. We have four strings. If a fault occurred in any of these panels, the maximum fault current will be like this right. In general, we can say instead of three strings, we can say n minus one where n is the number of string. If we have four string, it will be four minus one, will give us three multiplied by 1.25 multiplied by a short circuit. Now, if we have, let's say, for example, five strings in parel, and a fault occurred in one of them, then the maximum fault will be five minus one, which is four, multiplied by 1.20 54 over radians multiplied by the short sac current. As you can see here in general, you can see fault current through any of these fuses. For example, this one, since it's connected to this fault panel, you can see NP, which is the number of parallel strings minus the fulted circuit. It will be NP minus one, multiplied by 1.25, which is over radiance, bears the NEC standard. Multiplied by the short circuit current will give us a total short circuit current in the circuit. This is just four illustration. Now let's have an example. Now, if we look at any panel, we have some module specifications. For example, we have the short sc current, which is at the STC condition. Remember this at 25 celsius degrees, 1,000 watts perimeter square radians and er mass of 1.5. Also we have the open circuit voltage of the one module at also the STC conditions, NS representing the number of modules in series per string, how many modules in series. Also B representing how many strings in perel. This will help us to get maximum voltage and maximum current. Also I module over current protection rating. What does this mean, the BV module maximum over current protction rating? This representing the maximum views that can be installed for a BV panel. As you remember, we discussed dating in the previous lesson. Now, again, if the number of strings is more than three, then we will need to protect our strings with fuzes, the fuse length will be greater than 1.2, multiplied by the open circuit voltage of one panel, multiplied by how many panels in series to get the total voltage and 1.2 to accumulate for any increase in temperature, in any decrease in temperature. Because if you remember that when the temperature start is going down, you will find that the voltage or open circuit volt starts increasing. Now, there is a very small node tiers that we need to discuss or mention. As you can see here, 1.2, which is NEC safety factor. Now, also if that temperature goes down below -40 celsius degree, below negative 40 celsius degree, this factor will be replaced with 1.25. The fuse link also should have a current rating greater than 1.56 multi blood pi i short circuit, and this current rating of the fuse must be less than equal. The maximum f c spified by the manufacturer. Now, if we have less than three panels, then and the cable is rated at 1.56 multi blood pi i short circuit. For example, in a BV system with one or two parael strings, then we don't need any fuse except if the local installation regulations or codes requires them. But according to the NEC and according to the IEC, you don't need a fee or protection in one or two parallel strings. Let me make this clear. Let's say, for example, you are talking about this case. In this case, you don't need any fe fuses are out, and the cable will be rated at least at 1.56 blood by a short circuit. Here when we have number of parel strings greater than three, then we need a fuse This fuse will have this rating and this one, 1.56 mot by a short circuit. Now, what about cable, cable? We be rating of the cable will be greater than this values. We will have to select a cable that is greater than the fuse rating. For example, if the fe, for example, is ten pairs, then we need for example, a cable of 15 pairs any larger cable. We will learn how to size this precisely when we apply this to the two examples of the of grad systems. For example, you have this BV panel. Here you can see maximum system voltage, 1,000 volt DC. This is according to the specs of the module. You can see open circuit voltage and short circuit current at STC conditions for the panel, and you can see maximum fuse rating that can be installed, which is 15 pas. Now, in our system here, we have 18 panels in each string. So we have, how many string, four strings in parel. We have one, two, three, and four. We have four strings in parel. In each string, we have 18 panels in series. NS, which is series panels, 18, NP, which is a number of parallel strings are four. Now, the conductor sizing, we will learn about it in anoles. When we size the conductor and fuses in the of grid system. Don't worry about this. Now you can see that the maximum temperature 60 Celsius degrees, and the minimum temperature negative 30 celsius degrees in the allocation. Now the fuse length will be installed in allocation with a maximum temperature of 45 Celsius degrees. This will be looking like this. What we need to know is the fuses and conductors. First, let's look at the fuse. Let's look at the fuse. First, you can see here, the current rating 1.56, blood by short circuit. You can see short circuit of the panel here. Where is it here, 5.37, 5.37, and 1.56, which is a factor of NEC standard. Now, we are sizing for each string. We need the fuse of each string. The first string, for example, it will be 1.56 multi blood by short circuit. It will be 8.38 pairs. I'm going to look for a fuse with a rating at least this value. Now, the second condition, maximum system voltage, 1.2, multiplied point open circuit voltage, multiplied point number of panels in series. We have 18 panels in series as we said right now, and V open circuit of one is 43.1 and 1.2, which is the NEC effect. It will give us 930 1 volt. I'm looking for a fuse that can withstand this current and this voltage. According to Copper Pas men, and you will find the catalog and the products that they have in the attached files in this course or in the course files. We are going to select a fee from them, B V ten A ten F. This one can withstand 1,000 volt DC, which is greater than the required and have a current rating of ten pairs, greater than the required. We selected our fee, Now we need a conductor. You can see the conductor size will be 2.5 millimeter square and we will learn how to size it. This one can withstand the maximum temperature of 60 celsius decree and gives us 11.5 at this temperature. The 11.5 is greater than ten pairs, which is a fuse rating. The conductor is higher than the fe. The sizing of the conductor and fuse is correct. Now, what is this step? You can see this step is similar to what we said before? This is just two I tell you that you need fee. Because for example, the maximum short circuit here, flowing through any of these strings will be np minus one, which is four minus one, Multi blood py 1.25 Mutablod p short circuit. Similar to what we discussed in the previous slides. It will be 20 pair, which is greater than the capacity of conductor. It means we need as a protection. Now, what about arrays? Array protection is very, very simple. You just take the total current coming from each array and size the fuse based on it. Let's understand this. The same idea here, but the difference is that we have a system. A system consisting of a group of sub arrays. One, two, three, for example, number of sub arrays in parle bare array. We have 12, group of arrays that will be combined to form an array. Now in each sub array, in each one of these sub arrays, they have a group of strings in inside each sub array. Have let's say one, two, three, one, two, three, as an example. We have sub array one, sub array two, sub array three. When all of these are combined together, they will give us one array. Now inside each of these sub arrays, we have a group of parallel strings that will form this sub array. Now my own goal is to select the conductor. And fuse suitable for each sub array. Here it will be the same. If the sub arrays, you can see one, two, three, three sub arrays. All of them are parallel to each other. If a fault current, let's say occurred here, this one will provide current to this array, and this one will provide current to this array. Similar to the protection of string. The same idea here. If you have sub arrays in para greater than or equal to three, then you will choose the same speak as we adjusted it. In the previous slide. If it is less than three and the cable is at least rated at 1.56 Multi blood by short circuit, multi blood by E B. Now, why does the conductor is rated at this? Because each sub array, let's say, one, two, three, It will give us one positive and one negative. This conductor, so do we stand 1.56, multiblood by all short circuit, which is a conductor sizing. Multi blood pi have many parle strings. This one will give us 1.56, multibod by a short circuit, this one will give us the same value, this one will give us the same value. The total current will be number of parle, multi blood Pi 1.56, Multi blood by short circuit. That's why we have here n parallel. Now, if it is not rated at 1.56 and less than three then you need fuss. We usually don't do this. Now let's have an example. We have the same panel, which is the open circuit for 3.1 and I short circuit equal to 5.37 pairs, and the BV in installation, we have 18 panels in each string, and we have three sub arrays in parle. Now, if you remember in the previous example that we talked about, we had four strings in parle. We have four strings in each sub array. Now let's go. First, the first step is we need to size our fiel. How can I size my feels number one, the current rating. Let's say we have a group of strings, and this is strings. Let's explain it in a better way. You see this two, this representing the combination or the coll collection of these strings. We have here like this the collection of another string. Now, this two is the one on which I'm looking for. I would like to size this fuse. The current rating will be 1.56. Multi blo by short circuit, multi blood by how many strings in parle that will give us current flowing through this fuse. We have eight parael strings. Eight, not four parle strings. We have eight parallel strings in each string in each sub array. This multiplied by gives us 67 pairs. Now, what about open circuit or the voltage. For the voltage, it will be 1.2 multiplied by the open circuit voltage for one panel. Multiplied by 18, since in each string, we have 18 panels in series. It'll give us Mine three 1 volt. I'm looking for with a 67 pair as a current rating and voltage of Mine 31. We selected from copper pos men. We with 80 pairs and has a voltage rating of 1,000 volts. That is the first part. Second thing you can see here is the conductor size. Here in this, we selected ten millimeter square, and we will learn on 20, we will learn how to select this one. When we go to the design of the of grid system. So we selected ten millimeter square that will give us a 98 pairs at 60 celsius degrees. You can see maximum ambient temperature, 60 celsius degrees. We need a able that give us current greater than the fuse. You can see fee 80 pairs. We selected 98, which has a higher current rating than the fee. Okay Now, second thing here is that how many sub array, we have three sub arrays in parle. I would like to protect all of these sub arrays using fuses, array fuse links. We selected here this conductor and the f, each conductor and the fuse of each sub array. Now when we combine together using sub array combiner box, we will get array. We will have two terminals that will be the combination of all of this. How can I get the current flowing here? It is pretty simple. You can see here we have how many sub array? We have three sub arrays. You can see three sub arrays. Now, what is the current coming from each sub array? You can see the current coming from sub array, this 11.5 sixth circuit tabla by number of parle strings. It would be like this, this part. This multiplication will give us the total current in the system, total current in the system. It will be 201 pairs. We will look for a fuse that can withstand 201 pairs, and the voltage rating will be the same. Voltage will be 931, nothing can change it here. We selected from Co Postman, 250 pair fuse length, greater than 201 pair, and we will select a conductor or a cable, which has a current rating greater than 250 pair at 60 celsius degrees. Now, last thing which we will talk a put in this lesson is a fuses and the breakers required in the system. First, as you can see, we need a fuse for each BV string, and we said that we need a fuse or a breaker for each BV string. When we have three parllel strings or more. If we have a single or two parallel strings, then we don't need any kind of uses. Number two. As you can see here in the first example of the off grid system, we had two parallel strings, and this one, which is our charge controller, you can see we have the first input and second input. We will take positive end but it here and negative end potted here, positive here, and negative here. We don't need even any compier box. Why? Because we are not going to combine anything here. The compier box is used when we are going to combine strings together. Number two, we need also a breaker between charge controller and batteries. You can see here positive and negative going into the batteries. We need a circuit breaker or a fuse between it and the batteries. On the post terminal of the charge controller. Number three, we need also a breaker coming between the inverter and batteries. You can see on the post terminal again. Number four, we need also a breaker between AC louds and the invert. Between or to be more specific between inverter and distribution panel, main distribution panel at which our inverter is connected. Now, as we said before, this requirement are found in 690.9 A of the NEC standard, which shows us the protection of the fuses. If you don't remember, the one which we talked about, the over current protection guide in the previous lesson. Now according to barposmin, and this one is not necessary, but according to them, this is a recommendation, that you have to add fuses in the postive and negative termins. However, usually we add only on the postive terminal. Unless the local requirements or local regulations tells you that you have to add fuses in the postive and negative termins. Another thing is that when we select cables. When we have cables which are exposed to sunlight, we choose cables for DC X LBE. X LB, can we stand up to operating temperature up to 90 Celsius degrees. Or you can choose also any other cable with also the same rating at 90 Celsius degrees. You will see when I show you the NEC standard, this part in the NEC standard, when we size of grid system. Inside inside all of these cables that are inside are not exposed to sunlight, we choose a cable such as BVC, which has a maximum ambient temperature of 75 cys degrees. For EC and DC cables inside the house. Okay. Now, the first note here is that if you use fuses, let's say we have three parle strings and you decide to choose fuses. Then you will have to add a disconnected switch in order to isolate the BV system from the rest of the system. If you use fe, which is cheaper than circuit breakers, then you'll need a disconnected switch, something like this one. For example, you take the postive and end added here and negative here, take the postive and negative. When you switch this on the on state, it will be operating. The BV banner will supply electrical power, and when it is off, it will disconnect the BV system. You need this when you use fuses inside the system. If you use breaker, you don't need any fuses because the breaker can be used as a protection device and at same time as a switch. However, this two functions are separate fuses are used for protection of the BV system against a short circuit, and this connective switch is not used as a protection device, but it is used for switching. Now the rating of disconnect switch must be greater than the fuse of course. Now there is also another thing is that the fuses can be fuses such as similar to the one that you have seen in the previous lesson, or it can be inside the MC four connection. It can be MC four in line like this. You see this is an MC four connection. This one here. You can add inside it fuses as a protection. This is called MC four in line fuse. So that's all for this lesson. I hope this lesson is clear for you and you now understand how can we select protection devices and conductors inside the BV system. 52. PV Combiner Box: Everyone, in this last one, we were to cap out a very important equipment or component inside our BV system called the BV compiner box. The BV component box is available for at least three poller strings. What is the function of component box? Let's see right now. As you can see here, these are two component box. You can see how many inputs, one, two, three, and four. Here, one, two, three, four, five, six. This one, what does it do? It takes six input, six BV strings. For example, it provides us with one output. It compies the BV strings together. Similar to this one. This one is four input, as you can see here, four BV component box, four strings, converts it into one string. It combines them together. That is a function of the BV compiner box. The first function is that it combines or takes the different BV strings and combine them together. Now, you have to understand that, when do we need a component box? The requirement of a BV component box depends on the charge controller or the inverter. If you are talking about an of grid system, then it will depend on the charge controller. And how many inputs do we have? We will understand this in the next slides. As you can see here, the component box, in another view, you can see here the two terminals, positive and negative, positive and negative, positive negative, positive negative, and you can see here it takes the four strings and it gives us one compined string. That's why it's called the BV compin box, and in our case, string compin box. Depending on what it compins. You can see there is another output here for the earthing. Here, the protective earth comes out from this part. Now let's look at it more closely. You can see here we have the red, which are representing the positive input. All of this red, for positive input. Down, you can see here this down here. This one and this one and this one, this one, are the negative terminals. All of the negative terminals, you can see the black wires are combined together. All of the black wires are combined together, and as you can see here, we have a protection, which can be fee or it can be a circuit break. As you can see here in our case here, it is in the form of. Here we have our fuse for the first string, a fuse for the second string, another fuse for third string, and fuse for the fourth string. Now, behind this, we will all of the but, all of the red but are combined together, similar to the black wires. It will be combined together and we will have one postive wire. We have here r. This can be a breaker, or it can be a skinne switch. I here we have a breaker. That protects the whole string. It acts as a protective device, and at the same time it acts as a skint switch. You can see the postive terminal of the whole string combined together is input to the postive terminal, and the negative terminal, which you can see here, all of the plaque wires are combined together, giving us the blue line, you can see the blue goes like this and as an input to the circuit breaker. The circuit breaker has a postive input and post out. Now the two terminals of the circuit breaker will go like this one here, and the other one will go down here. We will take the two wires, representing the combination of all of these strings. Now we have another thing here, which is search protection device. What is its function, it is used to protect against lightening effect. It protects our BV panels against lightening effect. You can see it needs two inputs, the postive, And the negative. Now, the terminal of this one, you can see a protective earth will go out from here and go like this to the arsine system. When there is any lightening affecting our system, it will go through this device here like this to the Earth grid. Now let's look at this in another way. You can see here this is represented by this one. You can see we have positive and negative for each string. We have four strings, so you can see the first string, second one, and third one and f. Postive and negative. All of the postive wires having circuit breaker or fuse, as you can see here. These red wires after going after the fuse, after the fuse they will be combined together, and all of the plaque lines representing the negative terminals are combined together like this. Then the combined wires will go through one circuit breaker, as you can see here. You can see this PV combiner box is used against lightning protection. It houses or involves or contains the protection devices, such as over current protection devices, such as fuses or circuit breakers. It contains the surge protection device, and its main function is to combine the strings. Let's say I have a group of strings, and I would like to combine them together and have two wires. Now, you have to understand this combining a string or not depends on how many inputs we have. We will see this when we go to the first example on the of grid system and apply the rules of the NEC standard or the IEC. As you can see what we have here, the lightning protection device, fuses, circuit breaker, terminal box, and all what we have discussed. Here you can see the same wiring. The two positive and negative goes to the first two terminus. Also negative to the second input, pos negative third input and positive negative to the fourth input. Now, when they are combined together, we will have the two final inputs, which will go to the charge controller that will charge our batteries. Now at the same time, we have another output here for the protective Earth, that will go to the arsing system. As you can see here, what is the difference, nothing is difference between this and the previous one. We have one, two, three, four, five, six. We have six strings and they are combined together to one circuit breaker, and you can see all of the negative wires are combined together and go to the circuit breaker. This is a PV combiner box and I hope you understand now the function of PV compin box. We need this one when we combine strings together. This depends on the system we are dealing with. You will understand this when we do this on the first example of of grid system. 53. Selection of Fuses and Cables for Example 1 - Off Grid: Hi, welcome everyone. In this lesson, we will start applying what we learned in the previous lessons regarding the NEC standard or the IEC standard, regarding the selection of over current protction, and we will learn how to select the cables. We are going to apply this for the first example on of grid system. If you look at the first example, you'll find that we had only two parallel strings. We have only two parallel strings. This means according to the NEC, that we don't need any kind of use since we have only two parallel strings. Again, we don't need any compiner box in this example because we don't we have only two parallel strings, and the compiner box is available starting from three strings. We don't need again any compiner box. If you remember in the previous example or the off grid system, the first one, two parel strings, it means that we don't need any fuses. As a protection, and we don't need any component box. These four conductors will go directly to the charge controller, because the charge controller itself, it has two inputs, positive and negative and positive and negative for the first string and for the second string. These are the specs of the panel that we have used in this example. Now another thing, sense we don't need any fuses here as a protection. If you remember, we need what we need disconnect switch. ADC disconnect switch. We are going to learn how to select the DC disconnect switch for our system. It is very simple, similar as we did before for the fuses, which is 1.56 motor blood by the i short circuit. Here I'm going to select a DC disconnect switch for for each string. For this string, we will need a disconnect switch that will have a current rating of 1.56 motor blood by short circuit. If you don't remember, 1.56 is 1.25, for the over radians, multiplied by 1.25 for the NEC three hour continuous. Since the current will go through the disconnected switch for more than 3 hours. We need to derate this one by 80%. That's why we add the 1.25 factor. Similar to the fuses. 1.56, Mutablod by short circuit current, as you can see, 5.4 pairs, it will give us 8.4 pairs. We will look for a switch with this pair, and for the voltage rating, will be 1.2 safety factor, Multi blood by V open circuit, which is 47.8 Multiplied by, have many panels in seres in each string. We have two in seres. It will be 1.2, multiplied by four, 7.8 multiplied by two parael strings. It will give us 114.72 volt. We need this pair and this voltage. We found this disconnected switch, that will be used for these two strings together. It will take a positive and negative like this, positive and negative and takes here positive and negative. And that will give us the two terminals positive and negative positive and negative. This one will be used for these two strings. You can choose one disconnect switch that combines the two together, or it is used for this two together, these two strings, turn them on and off, or you can use that disconnect switch for this one, and a disconnect switch for this one. As you would like. The rating that we are going to use, which will be 32 pairs and 1,000 volt. This one is the minimum value available inside the market. 30 2:00 A.M. Pairs, greater than 8.4, which is enough for our application, and 1,000 volt is enough for 114. We selected the disconnects which now we would like to select the conductors here and here for each string. They will be similar to each other. What is the sizing of this sable? It will be 1.56, Multi blood boys a shot current at least So it should have a current rating of at least 8.4 pair. 8.4 pair representing the combination of the two factors, the over radians and the rating of the three hour EC continuous. Now you have to understand that the cable should give us 8.4 at the highest temperature of the location. If you remember that this cable or the X LB E, It will give us the current rating found inside the catalog is at 30 Celsius degrees. We will see this right now. First, we will look for the highest temperature in the location of Canada, which is our first example, which is 45 degrees. Okay Now let's look at this table from the from AC. The effect of temperature is that it leads to dating dating of the cable due to the high temperature. If you look at here, if the temperature at here at degrees, the dating factor will be one. So we are not going to deate our cable. As you can see here, the derating factor of 25 is 1.04 for X LP, X LPE. At 25 csus degree, we can overload our cable, 1.04, at 35.96. Here between them 30, here it is not showing. However, 30 celsius degrees, it will be equal to one. You are not going to date the cable at 30 celsius degrees. Now, the highest temperature here is 45 celsius degrees. The dating factor will be for the XL BE 0.87. I'm going to use this one as a durting factor of temperature. What I'm going to do is that I'm going to take 8.4 and void by a durting factor. It will lead to an X LB cable required of 9.7 amperes. Instead of cable, we can say conductor, not cable, conductor. We need 9.7 pair. Now there is another factor, which is called the grouping factor. What does this mean? You can see, we have how many conductors, one, two, three, and four. All of these conductors will be in one cable tree or one raceway. We have four conductors that will be beside each other until they go to the charge controller. All of them will be close to each other. They will lead to something which we call heat energy or it will provide heat energy to the neporing cables. So each of the cable when the current goes through it, it will provide heat energy. All of these cables will lead to heat energy or increase the temperature of the neighboring cables. In order to solve this problem, we need to add another durting factor called the grouping durting factor due to the effect of cables or conductors on each other. According to the NEC standard. If you have more than three current carrying conductors in a res away or a cable or a cable tray. These three current carrying conductors, more than three, you will need to date the ambasits. You need to add a durting factor. For example, if you have a way contains four conductors, you can see how many conductors, one, two, three, and four. 4-6, you will add a durting factor of 80%. According to the NC, we will use another derating factor 0.89 0.7. Divide by 0.8, it means we need a cable of 12.1 pairs. Let's make this clear. What happens here? We have a cable, let's say I selected a cable of 12.1 pairs. This cable should be durted by 80% due to the grouping effect because we have four conductors together. Second factor, which is 0.87, which is the effect durting factor for temperature. When we combine this two, when we multiply this two together, multiplied by 12.1, you will get the original required de current of 8.4 ampers. We have two derating factors, one for the groping effect and another one for the temperature. We are going to see the X LB conductors and select one, which is suitable for our application. As you can see here, the current current capacity, this is from Bachara cables, accompany for BV cables and many different other types. Here, as you can see, we are going to the cables will be conductors, will be in three in air. If they are buried under the ground, you are going to again look for more dating factors. If you don't know about this, you can check our cable support on our YouTube channel. You will find there about, more about durting factors and you will understand more beyond this course. As you can see here, here 12.1 pair, we need a cable with this current rating. As you can see here, 31 pairs, of 1.5 millimeters square. We are going to select a 1.5 millimeter square conductor for each of these conductors with a current rating of 31 and pairs, which is more than enough. 1.5 millimeters square cable from ba cables. Now, as you can see here, it says what it says at 31 pairs, or any of these current rating, if you look down here, at ambient temperature of 30 celsius degrees. As you can see 31 pairs, 31 pairs. It will give us th one pairs at temperature of celsius degrees. Since we have the temperature of 45 celsius degrees, that's why we add the dating factor of 0.87. However, when we said before that XL BE can operate at ambient temperature of 9 celsius degrees, this is the maximum temperature. You can see here maximum conductor temperature, 9 celsius degrees. It can withstand up to 90 celsius degree of operation. However, you have to understand that the increase in temperature, we will need durting factor. Now the next step is that we need to find the volt drop in our system. This is very important. Now, of course, the NEC standard does not give us or does not require the calculation of the volt drop. Why? Because we are not concerned or it doesn't affect the safety of our operation. However, it does recommend a maximum volt drop of 3%. The maximum volt drop from here to here to the loots is 3%. Or more precisely, it is recommended to have a 2% volt drop at the DC side. Here at this site, the volt drop should be 2% and at the AC sit here, only 1%. The entire system will be 3%. Now I have to tell you something here. The 2% here, as you can see 2% vot drop representing all of this DC part. Now, in my own calculation, I will consider the 2% in this part. Here. From the panels to the charge controller. Now, I will assume that all of these cables the charge controller to the batteries and the batteries to inverter and distribution board. All of these are very close to each other, so the volts drop will be neglected. I'm going to calculate the volts rope for this part only. Because all of these will be very close to each other and the volt robe will be very small. Let's start by our rule for voltage drop. The volt robe will be current, multiplied by resistance. The current here will be the operating current. I am concerned for the volts drop at the optimum condition at the maximum pointed tracking. Not the short circuit current. I would like to have the volts drop to be at least than 2% at the maximum power point. I'm going to take the current and multiply it by the resistance. However, you will find that the resistance is usually usually in ms pair 1,000 feet, which can be found from the NEC chapter nine, and I'm going to show you this right now. Or you can you can find it as ms pair kilometer. It can be Os Bare 1,000 feet, or it can be m's pair kilometer. Anyway in order to convert this ms pair kilometer two, ms only, you will have to multiply by the lens. Feet or kilometer depends on the country and the standard you are working with. You will understand now how we are going to do this. Again, volts drop will be current, which is the optimum current, which is a maximum power current, IMP, resistance which can be obtained from the cables or the NEC standard and length is the length of what remember lengths is the total length positive and negative. Y, Because if you consider the panel like this, like this as a DC source. We will have the post of wire and we have the negative wire. To salute. The volt drop on the wire will be the total length here the postive plus the negative. This is the total voltage drop occurring on the conductor. That's why sometimes we can say length of the positive and multiply it by two, or you can say length of the postive plus the length of the negative conductor. We take this one length of this one plus the length of this one. Okay. Let's look at the bajara cables here. You will see that inside their catalog, you will find for the 1.5 millimeter square cable. We have a resistance per kilometer. How much is the resistance, it will be the 0.7 a per kilometer. However, there is another thing you have to consider. Look at that temperature. You will see that the temperature here on the pair kilometer. You can see add to 20 Celsius degrees. At 20 Celsius degrees. It means that don't forget that the conductors here are operating at 45 celsius degrees the maximum ambient temperature, 45 cs degrees. As the temperature increase the resistance of the wire increase. We need to adjust this value into another value that is suitable for 45 degrees. We are going to choose to modify this value using this rule. Here, this is from another catalog called the lwd cables, and also you will find this inside the NEC and IEC standards. You will find this, don't worry. The rule, what does the rule say? It says that if you would like to find the resistance at any temperature at any temperature Sta Celsius degrees, it will be the original resistance at 20 Celsius degrees multiplied by one plus Alpha. Alpha is a factor will be point with this value for the copper and this value for aluminium. We are using copper cables, so we will use this value. Multiplied by the difference in temperature between Sta, which is in our case 45 celsius degrees minus the original temperature here, which is 20 celsius degrees. We will apply this rule. As you can see here, resistance at 45 celsius degree will be the original resistance, 13.7, Multiplied by one plus the copper factor, multiplied by difference in temperature. You will see that the resistance is now 15.04 s. We will take this one and use it here in our rule here. Assuming that the length of each conductor will be between 8 meters, positive and plus the negative wire. The positive wire 4 meters and negative wire 4 meters. The total length, which we are going to use is 8 meters. Now, what is the volt drop for each string? Volt drop will be five. What does five represent? Five, representing the operating current, which is the maximum power current, as you can see here. Let's go down here. I MB. Five pairs, the operating current, which is five pairs. Multiplied by the resistance, as you can see, the resistance, the pair kilometer, 15.04, the one, which is adjusted or modified for 45 Celsius degrees, multiplied by the length of the wire. You can see here 8 meters. However, as you can see here ms pare kilometer. We need this one, the length in kilometer. I take 8 meters and divide by 1,000 to convert from meter to kilometer. When we multiply this three together, we will get 0.6 volt. Now this is a volt drop on the first string. Remember they r barel to each other. We are not going to add this volt drop together. We are concerned with the volt drop for each string because they are parallel to each other. We have 0.6 volt. Now we need the percentage, so we need the voltage, the maximum voltage voltage at maximum power, which is 40 volt, and these two pens, the total voltage will be 40 volt, multiplied by two, The VB voltage of maximum power point, for the string will be two multiplied by 40, which is eight volt. We have our source eight volt and the volt drop on the wires, tell the charge controller. Remember, this does not exist, as we said before. These two wires will go to the charge controller. The percentage will be zero point 6/80. Multiplied by 100 gives us 0.75%, which is of course, less than 2% and it is acceptable. We found the voltage drop. Now, another thing which we have to u mention for the American students is that we have the American wiring gauge. Instead of the previous one here in the slides. Here you can see that I have chosen the per kilometer and millimeter square. In the American standards, we have the American wiring gauge, which it will be like this. You can see 18 AWG, 16 A G, 14, and so on, as this number decreases, tell one as number decreases. You'll find that the millimeter square will start increasing. And you can see here this is from the NEC standard. You'll find different types of cables, different types of materials. For example, you can see here 60 celsius degrees, these two materials, 75 celsius degrees, similar to the VC. As you can see here, 90 celsius degrees, as you can see here, similar to here. For us, X LBE will be in this catalog, which is 90 celsius degrees and the BBC will be 75 celsius degree. Another thing, which is the temperature correction factors. For example, for the X LE, I'm going to choose this values or use this values. You can see that if the temperature here in Fahrenheit, as you can see here in this part in farenheit, and the equivalent Celsius degrees. As you can see here if the temperature is four 9 celsius degrees 41-45 celsius degrees. 45 is the highest ambient temperature. You can see that the factor 0.7, 0.87, similar to the factor that we selected from IEC, the same value. So this is for other than 30 degree, F correction as a correction factor for cams. Here you can see again, if you look at the catalog, for example, you will you can see that AWG, 141210, and you can see the equivalent in millimeter square for each of these values. Another thing, here you will find that the DC resistance at 25 c degrees. Here in Om pair 1,000 feet, in the previous one from Bahara cables, we found it in Om pair kilometer. You'll find also for AC system if you use the cable as an AC. You'll find that the resistance at 960 degrees will be this value. And the inductance or the inductive reactants for the cable. Another thing which is a voltage drop and the many catalogs the use this one. You can see you can get voltage drop for any cable. It will be voltage, pair and pa pa 1,000 feet. For example, if you choose a cable of 14 AWG. What I'm going to do is that, I'm going to choose this value to get the voltage drop, it will be 4.684, and multiply this by the current, operating current, which is the maximum power, multiplied by the distance in f, so the length in feed. By using this, you will get the volt drop directly. This is another method. Here you will not need any correction factor for the resistance. Why? Because the volt drop here, the value given here is for 90 celsius degrees, F DC and AC. The volt drop here is calculated at 90 celsius degrees at the worst case. The second step is that we need to find the breaker or fuse between charge controller and batteries. How can I get the size of the breaker? It is very, very simple. Number one, we have to find the maximum current that will go from charge controller to the batteries. What is the maximum current? The maximum current will be the charging current of the charge controller. It will be a charge controller rated current, output a charging current. This is the maximum current that it can give. It cannot give any larger than this. Number two, since the current will flow here through the breaker or the fuse for more than three hour continuously. We need the C three hour continuous factor, which is 1.25. The maximum current, multiplied by 1.25. It will be the charge controller here gives us a maximum current of 70 pairs. Multi blood by 1.25 gives us 87.5. Remember, if we have even over radians, the charge controller will still give us 70 pairs. This is the maximum current it will give. That's why we don't need any other 1.25 factor. Now let's look at the standard rating for the breakers. Here at 7.5. Closest one is 90 empires. We'll choose a breaker with a 90 empires and suitable for the voltage here, which is 12 volt. Since we are operating at 12 volt. Number two, we need to select a able. The able must be greater than the Precor, which is the 90 am pairs. Another thing is that we have to add the C factor, the continuous factor, and number two, we need to add any durating factor. Number one, the temperature is assumed to be 40 degrees inside the house. This is an assumption according to the location. Number two, how many conductors we have, going into the batteries, only two, one and two. We have only two conductors. The first thing is that you will find that for two conductors, we don't need any groping factor. We don't need any groping factor. Groping de rating factor. Number two, the 40 degrees here, 40 degrees inside the house. We said that we are going to choose inside the house, cables of BVC right in the previous lesson. 0.87 is a derating factor at 40 celsius degrees. We'll just take the 90 empires and divide it by 0.87, which is 103 pairs. Now, let's look for a BBC is from LD cables, all of these catalogs. You will find it in the files of the sores. 25 millimeter square can give us 103 pairs, which is the one required. Free in air, 103 pairs for the 25 millimeter square. Again, again, we have here, remember that the 90 pairs here contains what? The maximum current, It contains the 1.25 of the three hour continuous. In addition to this two, we add the rating factor for the temperature, 40 degrees, 40 degrees for the temperature, and we have no groping factor. In the end, we choose a current rating of 103, which is greater than the 90 am pairs of the break. Number three, we need breaker or a fuse between inverter and batteries. What is the maximum current that will go through this invert? Maximum power. It is pretty simple. Remember that the 251 is the maximum but power. It will be the input, which it will be the input power. Divided by input power, divided by the voltage, which is 12 volt. What is the value of the input power? Value of the input power will be 250 divided by the efficiency of the inverter to get the input power going to the invert, divided by the efficiency of the invert. We have power divided by efficiency, gives us the input power going to the inverter. Then taking this divided by 12, it will give us the maximum current going into the inverter. And don't forget since we are selecting breaker, don't forget the 1.25, which is the N three hour continuous. Since the current will flow through this breaker for more than 3 hours. As you can see, 1.25, multiplied by rated voltage of the inverter divided by efficiency, multiplied by the battery voltage. However, this is very important is that we are looking for the lowest battery voltage, lowest battery voltage. Why? Because this will give us the maximum current that will go will go as an input for the charge controller. For the invert. How can I get the lowest battery volt from the specs of the battery? You can see this battery, which e 330 and pair our battery to 12 volt. If you go down here to this value, you can see this one end of the scharge voltage, the lowest voltage possible for this battery, which is 11.2. It will be 1.25, multiblod by albopower of the inverter, divided by efficiency, which can be found from the specs of the inverter. Here it will be 90%, multi blood by lowest battery volt, the 11.2 volt. It will give us 31 pairs. I will look for a breaker with a 31 pairs, one pairs, the closest to 135. We are looking for the highest one, the neckt higher value, which is 35. We select the breaker of the current rating of 35 pairs. Now, what about the able between batteries and inverter? Again, the cable will be greater than the breaker rating of 35 per, and we'll add the dating factors for the grouping and for the grouping and for the temperature. They are all of these components in the same location. They have a 40 degrees temperature and two condectors. We don't have a groping factor. We have a temperature factor of 0.87. Again, we are choosing VC. It will be 35/0 0.87, we need a 40 pairs. We will look for the catalog for 40 pairs. You can see a six millimeter square cable will give us 40 pairs. We choose a six millimeter square. Then for the AC Lots between the inverter and AC loots. When we are saying AC loots, I'm talking about the main distribution port at which it will start distributing all of the electrical power to the rest of the system. Between this and, we need cable and breaker. What will be the breaker? It will be very easy. 1.25 again for the three hour AC, multiplied by the maximum power coming out from the inverter. Which is the rated power of the inverter, divided by the AC voltage, here is the operating voltage of the system. Now, it will be 1.25 multiplied by 250 divided by the voltage. What is the value of the voltage here? Remember, since this inverter is a single phase, single phase. Since it is a single phase, and we are talking a poet, Canada, Canada In Canada, the single phase voltage is 120 volt, 120 volt. We will take this power divided by 120, give us 2.6 ampere. Now, let's say, for example, you are talking about a bigger system, a larger system, and uses a three phase invert. Then in order to get the current, it will be 1.25, multiplied by the power, divide by the AC volt, which is root three, multiplied by V line to line, or it will be three, multiplied by V phase. Since we are talking about a three phase in vert. Now let's use 2.6 pair. We will look for a circuit breaker. The closest one is a miniature circuit breaker, which is ten pairs. Ten amperes. About the cables. Again, it will be higher than the ten pairs and we will apply the same durting factor, which is 0.87, similar as before. It'll give us 11.5 pairs. Looking at the catalog, we have 1.5 millimeter square that can withstand 17 pairs. We will choose this one. That is how you can select the fuses and breakers, cables. How can you decide if you need a BV combiner box or not. I hope this lesson is clear and everything is easy for you. 54. Selection of Fuses and Cables for Example 2 - Off Grid: Hey, everyone. In this lesson, we will start applying the same rules that we have applied in the previous example of the off grid system. In this second example of the off grid system, we will select the fuses and kills. The example that we have here is that we had in the second one, we had three parael strings. I would like you to really really concentrate with me in this point because it will lead to some confusion. We have how many parle strings, one, two, three, right. According to the NEC code, if we have three parallel strings, it means we need a current protection, according to the NEC standard. However, you have to look carefully at the system here. If you look at the system, we have for the charge controller. It will be like this. It accepts one string, parallel to another one. It accepts two input. What are we going to do is that we are going to combine the two parallel strings together like this, combine them together, as you'll see in the next slide, we will combine them, and we will have two wires representing this string. The third one will be keeped as it is. We will combine these two together and keep this one as it is. Now, as you can see, we will have two parallel strings, and they will go to the charge controller like this. We have here two options. Number one, we can say that our system is consisting of two barel strings, so it does not need any over current protection. Or we can say that our system is consisting of three parallel strings, and we will need over current protection. Another thing which you have to be careful with is that let's say, for example, that these two parallel strings and one string alone, going to the charge controller. All, all of these are not connected to each other. You can see that we combine this two and we have two wires that will go like this and go like this. The other two wires will go like this. For example, if a fault occurs here, only this panel will give a current to the other panel, it will go like this through it since they are combined together. However, if this, this one is completely isolated right, it goes to a separate input. In this case, we don't need any of our current protection. However, however, if the charge controller, if the charge controller in internally. Connect these strings together. These strings together. It means that this one will start supplying faulty current from here and it will goes out from the second terminal. I know it is a little bit complicated, but in the end, I'm going to choose the worst case that we will have three polar strings that will affect each other in one way or another. We will assume that these strings are connected in parel internally inside the charge control. We have three parle strings, so we need over counterprotection. Number two. Do we need a compiner box? No, the compier box exist for at least three strings. However, you have to know that. When we use compier box. When we are compining three parle strings. When we are combining three parle strings. However, as you can see here, we will combine this two together, and they will go to this input, and this two will go as it is to the second input. What does this mean? It means we don't need again any compiner box because we will just combine two strings together. As you can see in this case, the combiner box will also be useless, so we don't need to combine all the strings together. Now, how can we select the over current protection? You have two options. Number one, select a DC breaker using the rule that we have discussed before, or you can select a fuse, then select a DC disconnected switch. We will start by selecting a DC breaker for string protection for each string. Remember that this two will be compined together, and we will have one combined string and this will be keeped as it is. We will talk about string protection for the single one. The charge controller selected has two inputs, as you can see, so we will combine the first two strings using something which we call MC 42 to one y branch connect to this one. You see what does it takes? It takes the two positive terminals, two positive terminals, and the two negative terminals like this and it gives us one positive terminal and one negative terminal. That is a function of the MC 42 to one because it takes two inputs and it converts it into one output. Number two, it's called y because as you can see here, it is forming Y shape. This one inverted y, like this. Let's talk about first, the combined branch. This two together. It will be the short circuit of the one BV panel, multiplied by the number of combined branches. How many branches are combined here, we have two combined branches, multiplied by the safety factor 1.25, which is the NEC over radiance factor. We will have 1.25 multiplied by two multiplied by ten, which is a short circuit current of one panel, two parallel panels and 1.25 41.20 54 the over radians. What does this even, why do we are doing this step? If you look at the MC and the MC four, the charge controller. Here, it has one input and another one. If you look at here, it says maximum B V, short circuit current. Now the thing that I didn't mention is that you can see here 50 pair, representing this current plus this one. Now, if you look carefully here, it says maximum 30 pairs per MC four connection. As you can see, we have the first MC four connection goes here, and second one will go here in this two and in this two. It says that we have a maximum 30 amperes as a short circuit current coming from each MC four connection. So the combined de bernches, will go to this input, one of the inputs. What is the current maximum current of the compind de bernche? It will be two multiplied by ten multiplied by the over radian fax This is the maximum current that can come from the compind de branch, which is 25, which is less than the 30 pairs, so we are in the safe side. You can see here the specs, electrical properties of the PV panel that we selected in second example. You can see here short secit current 10.07, which we have used in the previous slide. I I The current rating of the single string, this one, which will be alone, not combined. It will be 1.56, which is 1.25, for the over radians, multiplied p 1.25, for the NEC three hour continuous, which will give us 1.56, multiplied by the short circuit current. It will be 15 point 7:00 A.M. Pair. This will be the minimum current rating for the breaker. What about the voltage? Voltage will be 1.2 safety factor, multiplied by the open circuit voltage of one panel, which is here 38.9, 38.9, as you can see here, multiplied by number of series string. We have two series of strings. As you can see here, 38.9, multiplied by two gives us this value. We need a breaker with at least these aspects. We looked at circuit breakers. You can choose one pool, which can protect only the positive terminal, and you can also choose a two pool circuit breaker, which can turn off or cut both of the positive negative as you would like. For two pole circuit breakers that will cut positive negative, it has a voltage rating of 500 volt DC, which is greater than the required, and current rating the closest one to 15.7 is 16 pairs. We'll select a 500 volt and 16 pairs. The first solution is to use a few to use DC breaker. The second solution is to use a fuse, which is an alternative solution. Here is the current rating of the fee. You can see it is the same exact steps, 1.56 blood short circuit, which is 15.7, and same voltage rating. You can see we didn't do anything different from the previous slide. Then we're going to look for a fee. Here, this is from C oper Pus mean, Cooper Pusan company, and you will find this catalog in the files of this course. You can see 415.7, I'm going to look for something very close. You can see 16 and pair. We'll choose B V 16 and per ten F, which you can with a stand up to one than volt according to the company itself. You can see also here, 16 p here, 16 p, and you can see rated current, 16 p. Its number is B 16 20 f. Very important node here. Number one, Here, when we are saying that when we are sizing the fuse or a breaker, fuse or breaker. These rules will apply to both of these two. When I assume that the fuse or breaker are operating inside the house, or they are contained inside the house, not outside. If the outside, expose the two air and the temperature is greater than 40 celsius degrees, then you will have to apply another derating factor or a correction factor. What are we going to do is that we will take the current rating for the fuse, will be I short circuit, M blood by 1.56, which we always do. However, this time, we will add or divide by another rating effect. This is from the meson. I think I pronounced it correctly. It's called Men, a French company gives us this graph, which will help us to date our breaker or fuse. As you can see here, if the ambient temperature, let's say 50 degrees, you are operating the f in a temperature of 50 degrees. If you go up like this, like this, it will be approximately 0.9. For example, if the ps fuse is located inside a temperature or operating in a temperature of 50 celsius degrees, then what I'm going to do is that I'm going to take 15.7 and divide it by the d rating factor, which is 0.9. Oversizing the. Now, what about the combined string? We selected the breaker for the single string, and we need breaker for this combined together. It will be the same steps. For the two combined string, it will be 1.56, multiplied by the short circuit current. Multiplied by how many parle strings, which is 31.41 84 amperes. Number two, what about the voltage? Voltage will be the same? It will be 1.2, multiplied by the open circuit voltage of one panel. Multiplied Pi how many panels in series. It will give us again, the same value, which is 98 volt, as I remember, similar to the previous slide. We are looking for a breaker, which can withstand 98 volt and 31 pairs. The closest one in the market is 500 volt and 32 pairs. As you can see here two p, here two p, circuit breaker, 500 volt, and 32 pairs. Okay We selected the fuses or the over current to protection for the first conf the combined string and for the single string. Now we will need cable sizing. We have to select a cable for a single string. The cable rating must be greater than that of the f or breaker similar to as we said in the previous slides. The breaker rating is equal to 16 pair. Here, I'm talking about which breaker, the breaker of the single string. We need the cable of the single string. So we selected the breaker, 16 empair for the single string. Now, what is the temperature of the location? Here in the second example, we talked about Egypt, which had 50 Celsius degrees outside. I'm going to use a rating factor for what cable cable X PE. We said outside, we choose cables of ambient temperature, 90 Celsius degrees. One of them is X LPE, I'm going to look at the IEC, like this for the temperature. Another factor for the grouping, how many cables are going to the charge controller. Remember, how many conductors, not cables, how many conductors. We have 12 And one, two of the combined string. This two will be combined like this here, for example, and the other two cables will go directly to the charge controller. How many total conductors, the four, one, two, for the combined string, and one, two for the single string. We have four conductors in one cable tray going to the charge controller. According to the NEC standard, similar as we did before, four to six conductors means we have to use a derating factor of 80%. 0.8, according to the NEC standard, the current rating 16 mpeurs divided by 0.8 for the grouping effect gives us 20 amperes. Now, what about the temperature, as we said before, using the IEC table shown here, 50 c degrees? For the LB E 0.82. We will take the value of the current after derating of the grouping factor divided by 0.82, it will give us 24.39 pairs. I'm going to look for a cable that can withstand this value from Baha cables again or any other PV cables. All of this will find in the course files. In the course files we will find another catalogs for different companies, including German German company. Here for the current rating, you can see 1.5 millimeter square, can withstand 31 pairs three in air. 31 ps, greater than 24 required. 1.5 millimeter square, X LP. Now, what about the combined s steps? We have a pre for them of 32 ps, and we will add the grouping factor, again, which is 80%, like this, according to the NEC standard. 32 divided by 0.8 gives us 40 empairs. Then we will take the 40 pairs and use that rating factor of the temperature, which is 0.82. 40/0 0.82, gives us 48.78. I'm doing the same steps. It will give us, we will look for a cable that will stand 48 pairs. It will be four millimeter square. Gives us 57, which is greater than the required. Now the next step is voltage drop again as we did before. For the single string here, we selected 1.5 millimeter square, and it has a resistance of 13.7 at 20 celsius degrees. We will adjust this resistance as we did in the previous example. Again, we said we need a 2% volt drop at the DC side. And we will use the same rule here and the length is 10 meters. This is just an assumption. It can be any length according to the location and wires. Now, the resistance at the 50 celsius decrease. Adjustment of this resistance will be original resistance, multiplied by one plus copper factor, multiplied by difference in temperature between 20 and the existing temperature of the location, which is 50 celsius decree. This will give us 15.31 s. Now remember, if you don't remember this rule, you can get back to the previous video. Then we will start applying our role volt drop will be operating current for the single string. What is the operating if you go here, MPP current, which is 9.5. 9.5, multiply it by the resistance, as you can see here, resistance, which is 15.31, how many ms a pair kilometer. We need to multiply it by the distance in kilometer. It will be 10 meters divided by 1,000 to convert it into kilometers. It will give us 1.45 volt. Now, what the voltage coming out of the panel? It will be voltage will be the maximum power point voltage, which is 31.6 multiplied by two panels. Like this mata blood by 31.6, which is two panels. It will give us 6.2 volt. Now, what about the voltage drop percentage? It will be 1.4 5/63 0.2, which is 0.2, three, which is 2.3%. As you can see here, it is higher than the 2% that we need. What I'm going to do is that I'm going to choose a larger cross sectional area cable, which is 2.5 millimeter square. In order to reduce the voltage drop. What about the compound string, the same rules. For the combined string, we have for the four millimeter square, here exactly 4 millimeters square, 5.09/kilometer at 20 celsius degrees again. We are going to adjust 84 50 celsius degrees, which is the am highest ambient temperature of the location. It will be 5.09. Multiplied by the same rule gives us 5.69 oms. Then we are going to do the volt the drop for the combined string. It will be two y two because we have two parallel strings. Each one gives us 9.5 maximum power point current. Two, multiplied by 9.5, which is two parallel strings, multiplied by the new resistance, multiplied by the distance in kilometer. We are applying this rule here. It will give us 1.08 volt for the combined string. Now we need the maximum power point volt. It will be two multiplied by the same voltage, two panels. Each one gives us 31.6 at the maximum power point. It'll be 63.2, getting the percentage between them. It will be approximately 1.7, which is less than 2%. Okay. Step number two, we need a breaker between the charge controller and batters between here and here. So number one, we need to get the maximum current going out of the charger controller and multiply e p the C three hour continuous. Current rating of the breaker charger controller, multiplied by 1.25, which will be maximum current of this charger controller is 70 pairs. Mutabd pi 1.25, which is the three hour NC gives us 87.5 pairs. Looking at the standard, rating will choose 90 pairs and remember, these batteries are operating at 24 volt, What about the cable? Again, as we said before, for the cable, we need to choose a cable with a current rating greater than the breaker. It will be greater than 90 am pairs. The temperature is assumed to be 40 degrees in the house and there are only two conductors. 40 degrees inside the house, and two conductors. For grouping, we have two wires here, two conductors. We don't need any grouping factor. However, for temperature, we need a rating factor. So since we are choosing inside the house BV C, 40 celsius degrees, it will be 0.87. We will take 90 and vide it by 0.87, which is 103 pairs. So we will choose at 25 millimeter square that gives us 103 pairs. The same steps that we have done in the previous lesson. So we'll choose a 25 millimeter square BV c conductor from l Swed cables, and you'll find l Swedis catalog inside the files of this cores. Now, what about the breaker between batteries and inverter? The same role that we have said before in the previous lesson, 1.25 for the three hour EC, multiplied by maximum rated outage of this inverter, which is 1,500 what divided by the efficiency of this inverter, multiplied by the lowest battery voltage. If you look at the lowest battery voltage at 0%, here the worst case is 11.64. I'm going to choose this value as the worst case. However, remember, this for the one battery of 12 volt, and we have two batteries in seers forming 24 volt. The worst value will be 11.64 multiplied by the number of batteries in ss, which is two batteries. It will be like this, 1.25 multiplied by rated power of the inverter, divided by efficiency. Multiplied by the lowest battery voltage, which is 11.64. Multiplied by two, since there are two batteries in series. It will give us 89.49 pair. Then when we look for a breaker, it will be the same breaker 90 pairs, current rating 90 pairs, and the same voltage, which is 24 volt. And the cable. What about the cable, the same steps, 90 pair divided by the rating factor 0.87. You can see I remembered it. Since we have done the same steps a lot and the The cable sizing 25 millimeter square will give us the same value. Now, what about the inverter and e c loots or between inverter and the main distribution board to be more specific? It will be maximum power of the rated power of the inverter, here 1.25, multiplied by the rated voltage of the inverter divided by AC voltage. Divided by AC voltage. Here, it will be 1.25 Mt blood by 1,500, and the AC volt since we are talking about Egypt. The single phase voltage is 220 volt. If you have a three phase inverter, it will be root three root 33, multiplied by the V line to line as we have said before in the previous lesson. Similar as we did before. 8.5 amps, here we will choose a circuit breaker of ten mpiirs. Now, there is a very small node here that I haven't mentioned that Since we are talking about AC system, if you have a power factor, a power factor for the inverter, other than unity, other than power factor of one, you will need, let's say, power factor of 0.8, then you will need to divide the rated by the power factor, to get the volt air or the apparent power of the invert. Choose a breaker of ten empires, and what about the cable, we'll choose cable higher than ten empires, divide it by 0.87, the same dating factor. And looking at the cables, we have 1.5 millimeter square gives us 17 pairs, which is enough for our system. That's all for this lesson, I hope. You understand now how can we select breakers fuses and every component in our in our BV system. Now, remember that when we go to the hybrid system, the crete system, the selection of fuses, breakers, cables, the same procedure, nothing changed at all. I may not add this one to the hybrid and cred because they have the same steps. 55. Design an Off-Grid System Using PVSyst: Hey, guys, and welcome to another lesson in our course for solar energy. In this part, we will start talking about the BVS program and how to use it in order to design of grid systems, grid kinected system, and et cetera. So first, we have downloaded the latest version of BVSS. This is a last version at the time of recording this video. What I would like to do is number one, show you how to load this program. How to download BVss. First, you will go to Google like this and type BV like this and enter. Go to bvsst.com like this, like this. And then select this option, download BVS 7.4 or the last version that you see here. After clicking here, you will be able to download this program and then install it, and now you will have BVS. Now, the program will give you 30 days of trial to try their program. Now, let's get back to our program, and let's see how can I design stand alone or an off grid system. So first, the first step is to go to project like this and select what type of system you would like to design. A standalone grid connecting, bombing system, and et cetera. That is the first option. Now, you can go from here or you can select it from here. So if I click on a standalone like this, I will be able to design a standalone system or an off grid system. I would like you to focus with me or concentrate with me in this lesson because there are lots of very important notes that you will not find in any other video. This is very important. Let's say be the cyst of grid of grid XS one. That is the name of my own project. Okay. Great. Number two, I would like to select my site. So in order to select your site, you will have to go to here to click this icon, a new site to select the site or the allocation of this XB system that will be installed. You'll see that we can select any Any location we would like. In this large map, you can use the mouse to zoom in roll of the mouse, to zoom in and oom out like this, and you can go like this and select any location you would like. Now, this is the first option. You can click in any way like this, give it a click. One click like this. Like this, click anywhere to select that location. That's the first way. Second way is to type here the latitude and longitude and click on search. You can see here. If you click anywhere like this, you will see the first number latitude and the second number is longitude. You can see latitude and longitude of this location. If you go like this, you can see 7.89, which is the longitude, and 29 is the latitude. So longitude and latitude. Great. Now, what are you going to do? What are you going to do is very easy and simple. What exactly? Okay. First, you will go to Google Maps. Let's say we'd like to get the exact location, not just a country, but the exact location. So first, we'll go to Google Maps. So I will type here, Google. Google Maps. Okay maps. Like this. And then open it like this. Like this, Then if you go to any location, any location, for example, like this, you zoom in like this, like this, keep zooming in. No problem at all. Okay, like this? Let's say I would like to design here, for example, not this location, but for example, like this you click one click, and you'll find here this is a latitude and longitude of the location. This one. So if I click on it like this, you will have how much in north and how much. Now, someone will ask me, what does North, how much nor which one of these is latitude, and which one is latitude? So if you go here, you will find that latitude is related to north north and south. And longitude is related to east and west or west east and west. So what you can see here that let's get this one here. You'll see north north here, late, latitude. The first number here is our latitude. The second number here, which is 31, this one east east, here, representing that longitude. So we have latitude and longitude. Great. You can see this is a coordination here. This one, 29.53 and so 21 degrees. This is a location which is translated to this one. If I just click like this, you can see you can see here this number, Norse and, so we can copy this one. You can see a comma between them like this and go to B V program like this and type it here paste, and then search. You see is a 29 latitude and 31 longitude. Let's make sure of this. This is how you add any location to B Vss right. However, this is not the location that we are going to design. This one specifically here. Now, why this because we have this villa. And as you can see, we have a roof here, and on this roof, I'm going to add this or these BV penals. I'll see if it's suitable or not during our design. This is the exact location that I would like you can copy this or you can copy this. Both of them will lead to the same solution, not this one, but this one, the latitude and longitude. So I will get back to BV cyst like this and delete this and paste search. You can see 300.14, great. If you zoom in like this, it will be exact location that I selected inside the Google maps. Then I would say accept selected point like this. Now we selected our point, the location which we need in the country and region. Now, of course, when we are doing this analysis inside BVS. BVSst requires wind velocity, horizontal irradiation, global irradiation, and et cetera different temperature and different values related to the location. So in order to do this, it needs the information or data from a certain data base. So if you look at here, we have MTU data import. This is related to what data or what data base that we are going to use to get the information. You can use any of these. However, look, for example, this one, if you click on Import to get this data like this, you will say, Hey, but the AB IK. What AB IK, you have to know that. Some of these database are pay it. You have to pay money in order to get this data of this location. There are some which is free like Mtonrm and NASA, like this. You can choose between this and this as you would like. However, we usually use Mtonme. This is one which is very common between designers. Then click on Import to get these data for this location like this. And you'll see global horizontal irradiation, horizontal diffuse irradiation, temperature, velocity, and et cetera. Data related to this location. And you'll see 1991-2010. And you'll find sat, 34%, what does this even mean? It means that 34% of this data came from satellites, and the rest is from weather stations. Then we're going to say to save ES override, a, As like this, save. Great. Now you selected the location, and you imported the data related to location. Now, what the next step it says here, look at this rectangular pox. It will help you to know what the next step. The count has been modified. Please save the project. So I will click on Save and save. Then it says, please choose the plan orientation. If you'll see here orientation. Now, orientation is related to two properties. Number one, the Tilta angle and Asmus which we have discussed already inside our course. Now, you will see that number one, since we selected an of grid system of grid system. What happened here, you will see that here, optimization with respect to what winter? So the program automatically choose winter, as we have said before. Because if you don't remember, we said that winter is the worst month for production of electricity or producing electricity from solar panels. That's why the program selected winter for the of grid system. If you are with respect to on grid system, you will select a yearly irradiation like this to select to produce the highest energy due throughout the year, okay? However, since we are talking about an Ograde system and operating throughout the year, we will choose winter for off grade system. Great. Now, we have two conditions here. We have Delta angle. You can see we can control it like this, as you can see like this, and we have the Asmus which is the orientation, with respect to North South east, and west. Great. Now, first, let's talk about Delta g. Now you will see this graph. This graph here, which is plant, this shows you loss with respect to optimum. So if you can see as I change tilta angle like this, you will see losses as we decrease it, losses increase right. However, if I increase delta angle, you will see losses are decreasing until we reach zero losses, like this. So according to the program, zero losses occurs at an angle of 47 degrees. I I increases to 48, like this, 0%. Now, if you remember, if you remember, that I said before that in order to do or select the orientation in an off grid system, we select based on winter winter winter season. Now, remember that in order to select that angle, we said it is equal to latitude plus 15 degrees, if you remember, the latitude of this location is 30 degrees. So if we add 30 degrees to 15 or add 30 degrees plus 15 degrees, it will give us 45. So if I design it based on what I have just said in the previous lessons in the manual calculations, you'll find we have negative 0.1% loses, very small losses. So 45 is acceptable, and if you would like to make it more accurate, you can make it 48. Like this, both of them will be, great. Now, what about asthmas? Now, before we go to asm, you will see here fielotype, you can select between differ otypes. We have a tracking system, we have a fixed tilt angle, and et cetera. And since we are talking about an and of grade system, we use fixed orientation plan or fixed tilt. Fix angle, orientation, these types, which is fixed tilt angle that I have hast selected. Great. Now, what about Asmus? Great. So this is for plan orientation or Asthma. If you can see if you increase asthmas like this, look at this figure. Here, you'll see that this is losses inside the system. If you increase asthmas like this, like this, you will see losses increase negative 2.6. Now, if I decrease asthmas like this, we'll see losses increase. By default, it is zero degrees, right, right. Now, that is the most important question here, that this location is in Egypt, and Egypt is in the Norsn hemisphere, right, Northern hemisphere. Great. Now, since we are in Northern hemisphere, the Asma should be or the panels, should be facing South, should be looking at South. And the Asm as we learned before, is 180 degrees right However, as you can see here is that zero Asmus produced the optimum value. Now, how with this, we'll learn it inside the course that if we are in Northern hemisphere, we will facing the panels to the South, which means Asmus hundred 80. If we are in Southern hemisphere, we will facing the north, which means Asmus is equal to zero. How is this possible to have a zero Asmus and it is the optimum instead of 180. Now, this is very important and not anyone will explain this to you. Now look carefully here. If we get back to our calculator. Now, remember this website would print here, and we said that we can add or get a solar angle Asmus angle, using this calculator, however, it gives you by address City or Epcot. You can't add the latitude. If you type like this and enter, nothing will happen. So all you have to do is that selected the city. This is in a city called ese like this in Egypt. And it says your Asmus angle should be expressed as 15,075.2 degrees. 175.2 degrees. Clockwise from magnetic North or 180 clockwise from true north. So what does this even mean? This means that you can see that the Asmus is 175. However, in the program says zero angle, or we are facing the South. Now, I will explain why this happening. If you go to the BVSSt website, you can see plan Asmus this is very important and I will show you now, what does this even mean? If you are in Northern Hemisphere, the selected location in North in hemisphere like the example we have. Then the Asmus is defined as the angle between south and collect plan. And this angle taken as a negative towards east and goes into antitrignometric direction. So Sous plan Asmus equal to zero. If you would like to face this panels to South, then you will put Asmus as zero. This is completely different from what we already know we know that Asmus is angle from north, starting from North If I would like to face south, I will add 180 degrees. However, inside the program. It is not from North, it is from South. That is a difference. If you'd like to face South, you will put angle equal to zero. Now, the same idea, if you are in Southern hemisphere, then Asmus will be between north and collector plan, the opposite, which means that if you would like to face north, then put Asmus equal to zero. I know it is very confusing, but this is how they designed it. It's not my own mistake. Anyway, if we open Northern Hemisphere, similar to our location, Zero asthmas, it means that we are facing the south. That's what we would like to do. If we get back here and look at the problem, you can see panels are facing thus at zero asthmas. If you make it 180 like this, you'll see that panels are facing north, which is not what we would like to do, we would like it to face south at zero asm. Great. So we have selected Asthma and orientation. Great. Now, let's say okay for now. Now, before this, I will show you if we are in Southern Hemisphere. If you click on a new site like this, and selected allocation in Southern Hemisphere like we like South Africa. South Africa is in Southern Hemisphere. If you go down here like this, like this selected location, South Africa, which is in South emsphe. Now look carefully at the accept selected point and then import from Mt normal, for example, like this. Then click on k, save Don't worry, we will return everything to Pac to normal. Save and then we go to orientation. Now look carefully here. Save the project, whatever for now. Now, look at orientation, you'll see that zero Asmus north, what? It was south before, what happened exactly. What happened that the program zero Asmus in the north on the Southern hemisphere. It means that panels facing north completely upoite to the first one. So you have to be careful when you are designing. You have to look carefully, what is given to you. Now let's turn back everything to Norman. Again, I'm sorry for repeating some stuff, but it's very important. As I know, some of you will have an issue like this in the future. When you are designing BV system in different locations. So we have to understand this point. Now, as you can see, we're turning everything back to normal. Again, we are now in the same location that we selected before, and as you can see, Asma zero facing th because we are in Northern Hemisphere. Great. Then click on, we select the orientation. Now, you will see that we need to define our user needs. What does user needs mean? A. The needs representing the consumption that we have. Okay? We have to add all of the appliances or all of the devices that we are using in our house. Okay. Great. Number one, we will look at the short. Now, if you remember, example number two that we discussed, you will see AD four LAD, ten, what, 5 hours, one TV, 100 watts, ten, and et cetera. So let's add all of these to the application here. So four AAD, I will go to add four, like this, like this, we have four AAD and ten what, Forget about time for now. We will add it in a different way. Just to neglect it. Number two, we have TV. We have TV, one TV, 100 wt, one TV, like this, and for 100 wt, like this, for each one. Neglect se 5 hours, then we have more appliances. Let's make a fridge. Fridge. Let's go down here. We have two fans, 71, two fans, two fans for each 171. Okay. Then we have a fridge. Now look carefully at fridge in fridge, it says 24 hours. Why this, we said that the fridge is working for 10 hours. However, you have to understand that the fridge is always plugged in. So what I'm going to do that I'm going to see how much kill what hour consumed a bird day for the fridge. Be it's always plugged in. However, sometimes it works for 1 hour and shut down for 2 hours, works for 1 hour and shut down. You know that the cycle in fridge or any freezing application. So in order to get how much kilowatt hour, we simply will say one, we have one fridge or refrigerator, and how much kilwat? It will take three kilowatt hour, and I'll show you right now. So if you look here, one fridge, 100 watt for 10 hours, so it will be three kilowatt hour, which I put here. Now we have one laptop and one washing machine, 80 watt and 100 watt. We have this one, one, 300 what, like this, and we have one laptop like this, laptop, like this lap top, and for how much what, 80 what? 80 what. Great. Now we will need to define how many hours. I will go to hourly distribution like this, and then we will add hours for each device. First, we have L ED. We have LED working for 5 hours, and TV for 10 hours. You have to define when they are working. So you can see lamps. When you are going to operate these lamps. I will turn them on, let's say you have zero hour, which means 12:00 A.M. Then the time will increase. 12 hours means 12:00 P.M. 15 means 3:00 P.M. 6:00 P.M. And et cetera. Time starts from here like this in the clockwise direction. F D 5 hours. Each of these boxes, representing what representing half an hour. I will say they are operating from 6:00 P.M. For 5 hours until 11. 5 hours. I'm going to click Lift to click like this, half an hour. You can see another lift click, another one, another one, like this, like this. It works for 5 hours from 6:00 P.M. To 11:00 P.M. And you will see this distribution here 0-24 hours. Okay Now, again, you will see that if you would like to reverse any of these, simply right click. If I right click like this, it will remove this orange color. You will see 5 hours. If you get back here, you can see LAD 5 hours. It's automatically adjusted here, so you don't have to type it two times. Then we have TV. TV is working for 10 hours. Let's say it will be from 10 hours, let's say it starts from 3:00 P.M. Like this. You can click and just drag it like this and fill all of this 10 hours, right like this. And what about domestic appliances, which is our fan. It operates for 7 hours. Let's say it will operate in the morning at which the weather is hot, for example, 7 hours in the morning, let's say from 11:00 P.M. Like the 7 hours, 7 hours, like this. Okay? Four dishes, washing machine through 100 or 2 hours. So here, it puts 2 hours in this time. No problem at all. Now, we have then laptop for 8 hours. So I'm going to click like this, Laptop for 8 hours. If I would like to 8 hours, I will work, let's say from let's say 8:00 P.M. Right from here. For how much? 10 hours, if I remember correctly, 8 hours. 8 hours. Let's just right click 8 hours. Now, if now we have all of these consumptions, right? Now if we get back here, You will find that we have something which is called stand apoy consumers. How much what consumed depo stand standpoi devices. Remember that when we have a TV, that in a standpoi mode, at which the lamb just operates of the TV itself, and nothing else, this consumes a very, very small power, which is called stand poy mode. Now, how can I get something like this? Inside BVSSt, we exactly here. You'll see that here consumption of some usual appliances like this, and you will see that here, it says stand by five vo pap consumption, 120 what hour per day. We'll see that five vote pair dance. Five vote for each device, five ot. So I will get back like this. How many devices we have? LID will be turned off. We have a one TV, two fans, neglect, neglect frog two because it's working 24 hours. Laptop. We can say laptop and TV, both of them can be in a stand operation. So each one is five vote, so we will say ten t. Five what for each of these devices. Now, this consumption is 240 what hour. Now, let's see total energy. Total energy is 6,000, 660. Now let's convert to what we have already done in manual calculations. So see that 6,420 1 hour per day, great, 6,000 for hundred 20, and here 6,660, what the difference between them? The difference is that we have a 240 watt hour. If you add 240 to this value, you will get the 6,660 watt hour per day, grain. Now, you can see that now we have done the distribution. Now you can see that we have consumption defined by year. This is a consumption throughout all of the years of operation. If you throughout the whole year, if you would like to select for each season, let's say winter, we have some devices. In summer, we have some devices, and et cetera. All you have to do is select seasons right here. You will see summer autumn winter, spring, the different weathers. Different seasons, sorry. So you can select each of these. Let's say if I collect winter, then you'll add new values, spring, add new values, and summer as you can see here. You can do the same four months. For each month, you can do this, January, you can make February, like this. You can make March, and et cetera and you can return it to years. Now, let's say this is for January, and you would like to copy this in February. You can go to copy values like this, and then this is a source January, which is this one, and I'd like to copy it to April, for example, like this. Find this is January and April the same consumption. Now I will usually use years to indicate the consumption throughout the whole year. Great. And so we done this consumption and our distribution. Then click on like this. I will say again like this. Now define the system system. What does this mean means? Defining the BV system, banels, and batteries and finally charge controller. Great. Now look carefully here, number one, number one. This is very, very important. In the off grid system, in the off grid system of the BV st program, it doesn't give you inverter. What do you mean by this? It means that this system, it will give you finally DC. It doesn't have an inverter. In O grid, it doesn't have inverter. How is this possible? This is how the program works. So if you look at the simplified sketch for the system, Vray, we have batteries, and you can optional, you can add optional back up generator from here. But usually I neglect this one. You have PV system, batteries and final user. You can see there is no inverter in this system. That's why when you design, you'll find the charger controller, BV array batteries, user needs, you'll don't find any inverter. You'll find the inverters in on grid system. They didn't add this option of inverter in this in BV system till now. In all versions until now. Now, let's start with storage. Number one, we have accepted BL O L. This is representing It means that the reliability of the system is 95%. It means that there is a probability of 5% of not providing electrical powers. If you click on this one, you'll see loss of loot probability. So have a probability of 5% that the system will not provide the required power to the loot. If you would like to make it zero, you will have to oversize panels to prevent any kind of losses to the loot, okay. However, we usually keep it as 5%. And then we have autonomy, which we have learned before, how many days of autonomy, I would like one day of autonomy, right? We said that in our location here, if you remember here, we said that in our design here, we will select one day of autonomy, one day only. I will choose it as one day. Great. So it says that the battery voltage 24 volts. This is suggested by the program, exactly similar to what we selected inside inside the presentation. We said 24 volt for the same system. Now, the second step, select type of batteries. You have here different technologies. You can choose all manufactures or you can choose certain manufacturer as you would like I choose Deca, for example, like this, and you can choose all technology. You can select sum in and lead acid or you can choose one of them. Now, I will choose lead acid because the design of the system was based on lead asles get back. So you can see here we selected an EGM, 12 of volt EGM, 205 try to select the same to compare the two designs. So we have 12 volt and 200 and let's say 208 and pair ho, this one, gel. Now, what you will see that you can see open here, you will find all of the details regarding this pattery. Everything regarding the details of this battery. Now you'll see that the program selected two patteries in series because we have a 12 volt, and we need 24. If we look at here, you'll see the same idea, 24 volt, select two batteries in series. However, how many parallels? You'll see four parallel strings compared to two parallel strings. Now, what does this mean we need here eight batteries in my design and in the program four batteries? You can see double the value. So someone would say, Hey, this design is not correct. Here the program says four and you have done it. Now, look carefully here, and this is very, very important. Now, we said AGM, which is lead acid batteries. Now, we designed based on depths of Did charge of 50% to increase the lifetime of batteries. Now, this 50%, in addition to the temperature correction efficient, affected that design. Now, I know that you are not convinced and I will show you now by values. So we have a 50% 0.5 depths of discharge and 0.9. Now in the program, if you look carefully here, you'll see number of cycles at 80% depths of dscharge, 224 and the store the energy, 80% depths of Dscharge, eight kilowatt hour. Now, let's see first, number one. You'll see that daily energy, daily energy, 6.7 kilowatt hour, kilowatt hour. Now, you will see that the program designed based on 80%. If you use our calculator to understand this, you will get what I exactly mean. Let's just take this one here like this. Let's look carefully. 24 volt, we have two batteries in peril. Two multiplied by 208 gives us 416. So 24 volt multiplied po, 416. It gives us 9.984. This is how much kilowatt hour, the global capacity in kilowatt hour. Now, if we design, if we design based on 80% depths of this che, so multiplied by 80, like this. You'll sign 787987 or approximately eight kilowatt hour. You can see eight kilowatt hour, right. Now let's look at requirements. Daily energy based on what we have just obtained, 6.7 kilowatt hour, right, and we have batteries of eight kilowatt hour so if we divide this number by 6.67, like this, it will give you 1.2, this batteries can design, can give electricity for one day and 1.2 days, 1.2 days. So if you look at here autonomy 1.2, right? Now, however, this design is correct. In what case, if you choose 80%. However, you will see that number of cycles at this design is only 224. So it means that it will not last even one year. This cycles 224, if we assume one cycle per day, it means that these batteries will not even last for one year. So this design is not practical, right? We have to oversize or design based on 50% to increase the lifetime of these batteries. We can choose 80% if we selected, for example, L sam like this, lacum ion and choose the same manufacturer, let's say Panasonic, for example, like this. We have 48 k two, how many in seers? Let's sng like this. Figure it down in here, 12.8, let's say for example, 202, you'll see 22 and two similar as lead acid and 80%. But let's look at cycles 2,500 cycles at 80%, which means it can last approximately eight to nine years, right? It means that the first design of lead acid is not practical. I have to design it based on 50%. If I choose lead acid again, the same battery like this, this one. And if I design based on 80%, let's look at this. We have now our calculator like this, like this, and it says suggests capacity based on 80%, based on 80%. Now, let's say three to six, and divide it by 50%. I design based on 50%. I will need 652. If I make this one, let's say, three, for example, like this, you will see 624, less than what we need. If I increase it a little bit more like this, like this, you will see 832, which is more than enough. Since we need 652, 652 at a 50% depths of des charge. If we add even the correction factor 0.9, you'll find 724, and our design here 800 is enough to provide this value. Remember, this value is based on 80%, Based on 80%. However, we design based on what based on 50% for the lead acid in order to increase lifetime. That's why see eight batteries here and in our design here is also eight batteries. I hope you now understand this idea because very important. Now let's get back here. We choose also panels of zero hundred one. We will remember this. Then what is that temperature operating battery temperature? We usually said that we are putting it inside and in a condition of 25 celsius degree like this. 25 celsius degree. Now, we have finished design and you will see there is no error here. It means that our design is correct. Now let's go to V array. First step, you can see V array as most angle and et cetera. Number one, select the V modules. You can select anyone you would like or available now or whatever you would like to do. I choose LG, and I will choose similar to hundred hundred wat peak. Let's say, for example, this one, hundred w peak, mono crystalline, mono crystalline. Now, we have selected our PV panel, right, great. Now, it says, please choose the controller module or the operating mode for a universal controller. You can choose a universal controller, and it will just now you can choose a universal controller, and you'll find that, what does Universal controller mean, and MBT converter, maximum pow point tracking. It means that when you choose Universal, it means that you select just a suitable controller for the system. Since I don't know the market or I don't know what is available, controller, I would like just to design for now. So you select Universal control. If you would like to select an exact one, just take this, then choose a company, let's say vectoral Similar as we did before, you can see maximum pow point checking. Then you select what is a suitable suitable maximum pow point check? You can see suggested BV power 1784 for this system that we design. For now, you can see BV ray, nominal power 1008 program automatically. I didn't choose any. Program automatic selected one in sars, six in perel, giving us in the end 1801 p. That's the design of the program. Neglect it for now. The first step is that or the second step that we select a suitable MPVPT, close to this value, 1,800, which is the nominal power of the BV modules. Okay? So I will see what I have here, go down here, 1,800. So the closest one This 12, and remember. Remember, we have a batteries of 24, so I need 24 volt. You'll see 24 volt, number one. Number two, 1,800 what peak. If I go down here, 24 volt, starting from here, 1,800. The closest one is this one like this. You will see that the controller is slightly oversized, y oversized. Here, it changes the batteries. No, I don't want this. I would like to make it two in series, like this. And you'll see since this message disappeared. It means our design is correct. You'll see BV power, 1,700 suggested, and what we selected 1,800, two multiplied by three multiplied by 300. Two in series, three in series, two in par. So since two parael strings and one controller, it means that this controller has two inputs, two inputs, two MBBT inputs as we have seen before for these type of inverters. If it has only one, it will tell you increase number of controllers or divide it into two controllers. And you'll see the suggestion of the program strings 2-3 series 2-5. You give it more control on the design itself. And you'll see here the area required for six modules is ten meter square. That is the area that is based on the dimensions of these modules. Now, you will see also that number one, operating conditions for BV array. This is a voltage of MBB at 60 cs cree at 20 and the open circuit at negative in the worst temperature in the location. Now, these numbers, we have to make sure that between this and this, that these numbers are inside the operating voltage of the MABBt. You can see MBB operating voltage is 29-245. So we'll see these two numbers are in this range. That is the first one. Number two, the open circuit, the largest open circuit city two is less than the maximum input maximum volt. So you can see there is no error here. And the 24 volt, similar to 24 volt of batteries. So we have selected the right control. Now, let's see our design. Number one, you can see our design, selected six panels, 100, 1,800, exactly similar to the program here, 1,800. Let's see it here, as you can see here, I I If we go here for the rest, which was again, ectron, 2001, exactly at the program, panel connections, we selected two in series and three in parallel. You can see here two in series, and three in parle here, here we reversed it. No problem at all. In the end, it is a design. You can make it two in series. Three in, you can make sure from here like this. If you make this 12 and make this 13 like this, you'll see no problem at all, no error. If you make this three and two, the same idea, no problem at all. So both of these designs are correct. Now, we selected our batteries, we selected our charge controller. Everything is fine. Click on. Now, we have detailed losses, representing losses in our system due to resistance, mic losses, inside cables, soiling losses losing factor for the batteries. We make a default, as you can see here. This is losses inside our degradation inside the BV panels itself, and you'll find here more losses that you can add. Usually, we make them by default values as you can see here. Like this. Make all of this as default values. Then like this. Now we have more optional, like horizon and near shading. We will discuss this in another lesson. Okay, don't worry about this. Now, after finishing everything, save like this, and then run simulation like this. Okay, now the program did the simulation for the system. We can go to report like this. And you'll find here this is a simulation report for our project. Latitude, longitude, time zone location, how many arrays, their power, how many batteries, their type, capacity, voltage, results. You can see here performance. If you go down here, you'll find more details, can charge controller, batteries, BV modules, total power. The area required. You can see module area, 9.8 meters square, the area of one module. The cell area, and much more loss fraction, whatever these values that we said about losses, you can see here this is a distribution of consumption, and you can see here this is a power produced. You can see here, energy of user, energy mass and energy of the loot. You can see here, for example, a loot, which is presenting energy need of the user, E user energy supplies. This is the energy suppli from BV bana to user, and this is the energy of the loot required. You can see in most of these masses are very, very close to each other, except just one month, very small difference. The mass energy mass forte 0.72, a small mass of providing power to user. Very small value compared to this. You can see about 8%, a That's fine. And you can see here's the lost diagram for the system and much more. T 56. Notes about the Off-Grid Example: Hey, guys, in this lesson, I would like to give you some notes regarding the BV system program or the simulation that we have done in the previous lesson. The first thing is that you will see that inside the system. Here inside the system, you will see that the operating conditions the maximum temperature 60 celsius degrees and minimum temperature, negative 10 celsius degrees at which we use them as our boundaries. The wrest highest condition or the wrest lowest temperature. Now, I can control these values by going here. You can see here project settings here, and you'll find these temperature. You can see sec Celsius degree for the summer operating temperature, and you will see negative ten for absolute voltage limit, the maximum negative value for the highest or peak voltage. That is the first part. Number two, you will see here that we can design our system based on IEC or UL. IEC say that you have a maximum voltage of array of one than volt, For UL, it says you will have a maximum voltage of 600 volt. Depending on the standard you are following, you will choose one of these if you would like to do. Usually, I use IEC, of course, in our design. Okay. Now, another thing that I would like to discuss is orientation. Or before orientation, let's go to detailed losses. By default, I select all of these as default values. All of these as default values. You can see here this one as default, everything as default. Now, the first thing is that this one soiling is not the degradation of penons. I'm sorry. It is related to dust. The effect of dust, it will lead to losses inside the production of BV pants. So this is related to dust appearing on the BV panes. Here we have some losses. This is due to module mismatch. These panels are not identical to each other. There is a small difference between them. These difference lead to a small power losses, 1%. And here we have a string voltage mismatch. Since they are not identical, there will be a small difference in voltage between BV strings. Light induced degradation. This representing the degradation of VV panels in the first year. This is as a default value 2%, and this is efficiency of module efficiency loss, the losses inside the efficiency of the module. This is related to the omic losses. Here for resistance, you can select volts drop across each diet and you can also choose the resistance if you would like for this cable. Usually, I keep all of this as it is, as default values. Great. Now, the last one which I would like to discuss here is orientation. Now, we said we can control orientation as we would like and Asma right. However, there are some applications at which I can't control this Asmus or the stilt tank. Like what, for example, if you go here to this one, this is very common in Europe. You will find these houses, at which we can install here PV panels. We can put our PV panels here. However, on this roof, this roof is inclined by a certain angle from the horizontal. From the horizontal, there is a small tilta angle, which is inclination of the roof. So when I install BV penas, I will have tellta angle equal to the inclination of this roof. So for example, if this roof is inclined from the horizontal Pi, 30 degrees, it means that our telta angle is also 30 degrees. I can't. I don't have any control on it. That is the first thing number two, the Asmus Here, you will see that the panels are facing, let's say, for example, facing east, okay? So I can I don't have any control on the orientation of the south or the orientation of these panels. I can't to control Asthma. So the asthmas of the panel will be the same as asthmas of the roof. So this is an application at which I can't control orientation like Tlta angle and asthmas, and I have to put them as it is inside the BV system. So if I have 30 degrees asthmas and let's say inclination or 30 degrees Tlta angle and asthmas four degrees, then I will go to the program like this, and I will make this 130 degrees and asthmas for four degrees like this, for example, four degrees Asthma and 30 degrees Telta ang. Okay? Now, of course, these are not the optimum condition, you'll see that there are losses with respect to optimum 4%. Okay? However, I don't have any choice. I can't control these two values in a project like this one. Okay? That is what I want to discuss in this lesson. 57. 3D Shading Analysis in PVSyst for Off-Grid System: Hey, guys, and welcome to another lesson in our course for solar energy. This lesson we designed or in the previous lesson, we designed our BV system. Now, we would like to do the shading analysis, the three D shading analysis. So we have here two options here for horizon, which is fire shading, due to fire objects like building buildings in five to 10 kilometers, and we have near shading due to the components or due to the buildings or trees, any building structure close to us, okay? When we would like to do shading analysis, we start with near shading like this. Then after clicking on near shading, number two, click on construction and perspective in order to draw the building and the BV panels. We have here east, north, south, and west. What I would like to do is to draw our building. If you get back to our drawing here, This is a project that we are chalking about. We have, as you can see, this is the highest part in the building. I will not draw all of this. What I'm concerned with this part only, because this is a higher part, and this is a part at which I'm going to install my BV panels. I would like to draw this. In order to draw this, I will need these dimensions, these dimensions, the lengths and widths of this building. Then we will add another one here. Now, before we see how to do this, I would like to show you the different options that we have inside our program. So as you can see here, if you would like to create any element, you will say create like this, and you can choose elementary shading object like this. Now, this will give you different options. If you have the shape parle pipes or for example, go like this, you will find a bras, If you go like this, you can find a house with a two sided roof like this one, classical one. You'll find here one, two sided like this, which can be useful in some constructions like the parking area for parking area for cars. You will find here you can add a tree. You can add a window tur pine. You can add any thing that you would like. There are many options here that can help you to construct what you exactly want or what you would like to do. This is the first option. After this, you can click on render like this and you will have your own shape like this. Now, if you close like this, you will see that this object render again, you'll see that this object is now added. You can see parallel pipe. You can see it is added now to the program, and you can add your BV panels and et cetera. Let's show you another one. If you click on it like this and delete like this, then go to create, and then you can elementary shading object like this. Again once more. Let's show you how to control dimensions. Let's say you have a house with a two side roof like this one. You can control the height z. You can control lengths. You can control width of this building. You can see x, y, and z. The three xs. Now, for example, you can see that dx is 8 meters. This lens from zero to this point, this length is x x, as you can see here. You can use measure like this. And as you can see here, you can see 8 meters. This is a distance in X xs, and this is a distance in y x, approximately 12 meters, which you can see here. If you go up here like this, Z is approximately like here. So let's just skip, click like this and here. So it's approximately 5 meters like here. Neglect this part, exactly, it will be 5 meters. Anyway, you can see here, for example, if you have dx, 8 meters, if you would like to change it, you can see here 8 meters, you can control it like this until zero, x and increase it again. You can control y, decrease y20, and increase y again. You can control the y axis or the axis from here. You can see z is increasing as you can see here. You can control like this these outlets of this building, which is called eaves here, double eaves and lateral eaves, like this. So you have many options you can do also. As you can see, when I control this, as you can see here, by controlling this part here, you'll see I can change tilt angle. If I have a roof of 30 degrees, I will simply say 30 degrees and troll like this. So this roof is now inclined by 30 degrees from the horizontal. All of this depends on what you see in the location itself. Okay. And you can see here if you control this, you can control Z. This one is related to this one can control Z, yes. However, however, it controls approximately the tilt g, control silt g. This one control height of the building, as you can see here. 14x and y, x and y, this one related to lateral eaves and gable eaves, and this one is related to tilta angle, this one related to z or the height of the building. That's stop illustration or help you understand. Now, if you would like to move this drawing, you can simply use this hand to move like this. You can use this rotate to rotate and look at the building in different views like this. You can look at x y view like this, two xs, x and y. You can look at x You can look at Y, as you would like can zoom in like this and zoom out as you would like. So this is how you can control building like this. So this function elementary shading object to add just one object. Great. No. Currently we have this. Now let's get back to our drawing, and I will tell you why. We have this building. Let's say this is a roof that we would like to add. We will assume that we are talking about this part only. This part. And add this above it. Let's first see how can we do something like this. Number one, I will see the distance here length and width. So I will click like this and measure distance. You can take this point like this here. I would like to measure this lengths like this to here. I will click like this. It will give you approximately 11.9. If I just make it like this, it will be approximately 12.8, Approximately, of course, you will measure this in the location itself, but for now, we are just measuring it using Google maps. So let's say 12 a meter as a length, and the web itself is approximately 7.4, 7.4 and 12. So how can I do this? Get back here? To the program here and first, create a building. Since we have several elements that will be combined together and form as our building, not just one element, but a group of elements. I will go to a building like this, double maximize this and it will open you the same settings, everything. Then I will click on add object like this, and then I will add this shape. What are we going to do? We simply will select a parallel pipe like this, and we can have this square shape. Now we can control the lens and with, let's say lens equal 212, If I remember 12 meters, and the wed is if I remember seven point, I totally forgot. We have here 12 meters and let's say 7.4, 7.4, and 7.4, like this, and 7.4. Then zoom out this. We have this large roof, and then we will control its height. We have 12 meters and 7.4. Now control height height of this building is, let's say, we have a vela and we will understand or we will know that this Vla for example, is 9 meters in height, like this. We'll have this roof. At 12 meters here, we can reverse it, we can make it this 112, and make this one s, control z to return back, make this 17.4, and make this 112. It doesn't matter, you can rotate it in the end to make it exactly similar to this figure, like this. Then we can rotate it like this to look at it in another view like this. Like this. Now, clothe this object. Now we have this object. We can double click on it again once more. We can simply click on this one. Again, if I would like to modify anything, it is an object from here, and then I will make it color, let's say, the same color. And render, this will be our first one. Okay. Great. Now, I would like to add the second object here. This object will be, let's say 3 meters in height, and let's see it's dimensions. Let's say this height of this part is 3 meters, and let's see it's a dimensions, like this. This part, I will take it from here to here. 5.6, and 4.2, 5.6 and 4.2. 5.6, so we can add another one. 5.6 and 4.2, like this, and its heights meters, like this. We will make it color, let's make it a little bit drcal like this and render. Then close the object. Now, you will see this is our object. Now, you can see it is down here. I would like it to put it up here. What I'm going to do is simply I'm going to rotate like this. You can first use x Y V, for example, not x y. Let's make it Z, Z. Then I'm going to move selection and move it up like this to make it accurately above this building, like this. Let's look at another view like this, and it will be just click on this one and drag it like this. If you look at this three D view, congratulations, you have added the one successfully or this shape successfully. Now you can see this is larger than this. Let's make sure of this. This is a lens, and this is a widths. Lens and widths. Great. Now, we would like to add this other object. This one, This is small one. It will be from here to here, let's say 3.4, three point just again, I like this from here to here, 3.4 and 1.9, 3.4 and 1.9. 3.4 and 1.9. 3.4 0.4 and 1.9. And let's say this height is 2 meters. All of this will be measured inside the sight itself. Let's make its color a little darker, let's say this color, for example, like this. Now, how I can adjust it, simply go to x y. It is exactly here, go to x, not x then you can see here, Here to move up in the z axis. If you'd like to move in x axis, you simply click and drag like this. If you'd like to move up, simply you have to go to axis like this. Sorry. Click on this one and drag it like this. Okay. Let's look at the other view. X y. Okay, great. Sorry Let's make it in three D, and let's look at our object. This object is where exactly. Let's look at here. It is exactly beside it. Beside it. I will move it like this. Drag it like this. Let's look at the other view. Okay. Great. Okay. Now we have the two objects beside each other. Now I will have to add our panels, right. Okay. So this all what we did right now is that we have this shape for a building. You can see this is a building consisting of three object similar to this one. Okay? So it is now one plaque inside the program since we selected building. If I close this one like this, you will see one building. You can see one building together. You can even if you click on Modify, you will be able to move all of this building together as one plug. That is the benefit of doing the building structure. Okay. Now, what next next, we would like to adjust our building, similar to with respect to North, South, West, and east, with respect to the reality. What do you mean by this? If you look carefully here If you look carefully here, is the north. The perpendicular line a port representing north perpendicular line north in negative direction east and west. What I'm going to do is that I would like to rotate this building and form an angle in order to adjust this exactly with north and south. How can I do something like this? If you go to this one, If you go here, this is using Google Chrome, you'll find an ex, an extinction called called what called protractor here, protractor here, which is used to measure the angle. With respect to another location, you can find this extension inside Google Cro. If I click on protractor like this, you will have this shape. If you'd like to move it like this, Like this. We have this norse here, and I would like to find the angle between south, which is between here, take this one and drag it here. We have nose south right. Now, this is the other direction. I would like to make it perpendicular, as I can. Of course, this is just an approximation as I can. So we have this building, looking at this direction with a certain angle between it and south, right. So we have south green, and this one is the direction of this building. Now, what is the angle between them? You can see here, 50.1, if I would like to make sure if you move this one, you'll see angle zero until here approximately 50 degrees, perpendicularity. So we have 50 degrees with respect to two south. That's what I'm going to do. I'm going to the program like this, and I'm going to adjust this to form 50 degrees with south. So we will see that here, we have this building. If I choose 50 degrees Asmus zero, means it's facing here. This is the direction of this one. Now what I would like is to adjust it like this. What I'm going to do, let's say 50 degrees and see what will happen in S Zaprok. Now, you'll see it looked in this direction, right? However, however, you'll see here, like this north. You'll see it is looking in this direction. If you look at here, looking like this. It means that in this program, if I say negative 50, it will do what exactly what I want like this. If you look carefully here at this one and this one, you'll see they are exactly similar to each. It forms 50 degrees with south. As negative 50. Similar to this building. Great. Now, what, the next step is to add our panels, O BV panels. I will go to create and you have different options for BV panels. I will choose rectangular BV plan. Remember, we have two barrel strings and three in series. We have we have six panels, six panels, six panels, three in series and two parel right. We have total of six of these panels. The first step is that we will go here. You will see Delta angle and sms. We will exactly have control in them, if you remember, we have control on them. From what we have learned. If I would like to change their size, remember that these panels will be on one row and other panels will be on row. I will divide the two strings into two rows. One row for a string and another row for a string. Each row has three panels, three panels. I'm going to choose here three panels. Like this, how many in x xs and how many in y xs. First, you can choose between landscape and portrait, can be like this, and it can be like this. Landscape and portrait, this two Pi width and Pi lens. Now, how many modules in x xs, you can see how many in x, one, two, three, four, four, how many in y xs, one, two, like this. I will have only three panels. I will make it three in x xs, like this three in x axis, and just one in y xs, like this. You can see one, two, three, one, two, three. If you look at y xs, we have one. If you look from here one, if you look from here one. If you look from here, three in x x, like this. So this is a first string. Great. Now, what next, we will need to define partition. What does define partition mean? How many rectangular rectangular strings, how many strings? How many rectangles or how many strings in x xs and in y axis? How many number of rectangle strings? As you can see, we have one string, right if I look in x xs one string and in y, one string. I make this one, and make this 11, two. Like this. Number of rich tan. All of this is one string. Okay. What next? We did this one, so we have to close like this. And as you can see, we can't even see it. Let's just do x y view like this. Move it in this direction, and then in z xs, like this, move it upward like this, click here and move up, move up like this. Like this, and do x y again like this. Let's move it like this, and like this, like this, even you can see the shadow of the BV system. This will help you to provide space between these two, like this, let's see it in all view, like this. You can see we have this BV string floating a little bit. Let's just make it the same height modify. It's a height 9.11. Remember this is a height is nine. I will just provide three centimeter, because the program suggests this. It will be not just touching the ground, just a little bit higher. Not just above the building exactly because the program itself tells you that you have to two to three centimeter as a distance between them. Now, what next go like this? We have the first panel and with their own shadow. Now the next step is that I'm going to copy this. I will select like this. C double click or go to here, then copy or control C, and then control V like this. Then you can control it in y x is like this. Like this. We have two, double click here. You'll see that we have three, and this also forms one string. The same exact settings as this one. Now let's look at it. Great. What next, we would like to see the effect of shadow of this building first. What I'm going to do is to go to shading animation tools and then shading animation like this and use a step duration. 1 minute, you can use 1-15 doesn't matter at all. 15 will make the simulation faster. As you can see day of year, which is a day at which the sun will be very close to the ground, close to the location itself. If you remember, in the Northern Hemisphere, we said that 21 of December is the closest to earth. If you are in the Southern Hemisphere, it will be 21 of June, right? So here we are talking about December. Let's run this animation and see what will happen exact. Okay, you'll see that there are some losses 2.5% on this day. Now, if I would like to return back the animation like this and see why this happening. This happen, you can see this panel provide this shadow on this one, as you can see here during this part and at the end of the day. What you have to do? You have to move this one a little bit far. If I click on this one, seen objects, modify, and then take this one, a little bit away like this. Let's see clearly. Okay. Let's move it a little bit like this. Okay. Now, let's see the view. Everything is fine. Now let's see if there any difference will happen. Go to tools once more. You can see 2.5%. Let's run once more. You can see 1.6, let's see this animation slowly. You can see still a small part due to this chat. What I can do again is that I can modify this one, s this one and move it a bit to the right like this and a bit toward like this. Let's see, this one is floating. Floating here. Let's move it a little bit to the left. Let's see if it is possible. Yeah, exactly like this. Okay. Then I will run this analysis once more. Let's see what happened exactly. So there are still some shadow here. Due to not these panels, but this building. I'm going like this. As you can see, it is just a form of trial and error. Let's see. A little bit to a forward like this. Let's run once more. Let's see a very small part due to this one. If I just move it a little bit to this one, move it a bit forward like this and move a bit to the left. Let's see if possible here. Okay Let's see small part of this panel. We can just make this one. Bit like this, a little bit like this. It is just form of trial. Let's see if everything is fine. This one is out of boundaries. Okay. Like this. Here, this one. Okay. Let's see if it's better or worse. Let's see here. This one is floating again. There's another option that I would like to try. Okay? This one, can see this one. How about we can double click like this and make it a port for example like this and clause? We have this in the form. Three panels in. Let's see if this will make any difference in the electrical losses. Yeah, it is much better right now, as you can see here, very, very small part. Now, since we did this simulation for this 21 of June 21 of December, we have to do it again for the reverse direction, which is 21 of June, 21 of June. Then run once more. Now, you will see on the other side. You can see on the other side, this building affected all of these pennants. What can I do in this state? You can see this one, covering all of this, because it is very close to it. All you have to do is you have two options. Number one, is to take these penons and put it here if it is possible, because this one affected the production of electricity. You can see very high losses during the next day, this day. If we just take it like this, Okay. Like this, take down. You can make it in x like this. And move it like this. Like this. And let's see. So this can be possible too as to put one here and the other one here. Okay? Let's see if this will make any difference for us. You can see here, almost zero electrical losses, as you can see here, very small losses like this. If you would like to save this one, all you have to do is save like this and make it let's save for 10 seconds and best quality. Save it on desktop. Play the animation, and you will see this is the animation for the shading effect on this location. This is in the morning and then after this when this is a start and the end. Now, what else you can also, if you would like if you have a trees? If you have a tree, you can simply add a tree like this, create elementary or shading object, select tree. Like this, You can control this diameter of this trunk. You can also change its height. Let's make it seven, for example. You can see it becomes larger. You can control these dimensions of this tree, this height, and it says you can render like this, and you have a ice tree. You can add this object here, x. Let's move it in this direction like this, and in x xs. Okay. Let's look at X Z. Like this. Okay. Let's look at three D V. You can see we have this tree. You have this tree, that can cause a shadow on the system. If I would like to do this, you can say Run. Let's see if this tree will affect our BV system. Again, as you can see, zero losses, if I just make it like this and like this to see how it will affect my design like this. Let's see if it will do anything right now. Okay, nothing again. Why nothing because this one is on six of June. Let's make it December once more, like this, 2021, and run. Now, you will see electrical losses due to this tree. What I have to do is to again, if I have this tree, I will move it like this. And see if this will help me at all, like this. You'll see electrical losses becomes smaller. L et's make it a little bit away like this and move it like this and see what will happen. Again, due to this shadow effect, still we have if I double click like this and make this one. You can see this is how you can solve this problem of chad effect. That's why this analysis is very helpful in many applications, like this. Let's run once more. Okay. Great, as you can see here, zero losses. Now let's get back again to June like this 21 or June. You can see again, this one affected us. The other option is to take this one and put it here. If I just make it like this and move this one like this, this is one option. But the tree will also affect we have two buildings that affect us. The other option is to take this and put it here and try to some space between like this. For example, if we go like this, like this, click here and drag and go down like this, and like this. Let's see in three D view. Key like this, take it here, take it like this. Take this one pack. Let's see this view. Okay. Let's try and see if this will help us to prevent the shading effect. Zero losses. Now, let's go here and see on December 2021, run once more. 1% losses due to this one, very, very small touch at the end. This is how you do analysis or the shading effect analysis, then we will go to table here. Recompute clause. But first, according to module strings, we would like to see the simulation shading depending on strings, and we divide them into strings. Then we'll go to. So we have done the near shading. Hizon is for far objects, buildings in five to 10 kilometers. Now, what I'm going to do is simply, I'm going to get it from read and import to get that data from weather station. But first, you already know about this curve, the sun curves sun paths, as you see here, e paths representing the movement of sun, for example, this one, representing movement of sun on June, this one, representing movement of sun during December. Then we will say read port and you can select any database you would like. Let's say Mt or BVGs, BVS, import. It obtained all the data for the horizon. Then we are going to save once more like this, and then run that simulation and reports like this. Now, this will show you all the details that we discussed before, like this. However, there is an additional part due to shading analysis. You can see building, PV panels, the tree, and you can see this are the losses, as you can see here, these are different types of losses during different parts due to this panels. These panels affect this panel, affect this, like this. This is how you do the shading analysis in B V cyst. 58. Example on Design of a Hybrid PV System: Hi, and welcome everyone to this lesson in our course for solar energy. In this lesson or in this lesson, we will talk about with the design of a hybrid B visa system. So if you don't know a hybrid PV system or you don't remember when we give a small hint about what the hybrid system. So the hybrid system is consisting of solar panels that will provide electrical power. We have here our loads, and we have inverter that will have a solar charger insights that will charge batteries, or an AC charger also, it has a solar charger and easy chosen. This inverter can accept input from a power grid or degenerate. So again, we have here our loop, as before. We have our panels that will produce electrical power or DC power. Now, the inverter itself for here is called a hybrid inverter. You can see everything in the system is connected to it. You can see we don't have a charge controller in this type of system. We have one big inverter. So what does this inverter do inside this inverter? It consisting of several components, are several circuits inside it. So we have solar panels that it will take the input from solar panels and solve it. We have a solar chargers that will take the power from the panels and start charging our batteries, our batteries. And also it can, from the same two output of the inverter. It will take as a power from the battery and convert it into AC for our loads. And also the inverter or this hybrid inverter can take AC input from the grid or a diesel generator as an input to it. And in the bypass mode, it can provide electrical power directly to the load from the generator or the AC grid. Or it can also have inside it a charger or an AC charger that will take this electrical power and the charges, the batteries. So you can see all of this is done using one big device or equipment, which is a, involves. The steps of design here would be a little bit different. And not the layer, not a big difference between it and the off-grid, but it is very close to the design procedure. So first we will define our loads as we did before instead of grid systems as then we are going to size our PV panels. Here you can see we don't select the inverter. We go to the sizing of penance, and then we are going to select a suitable inverter. Then we will size our batteries. Then we will connect as our panelists based on that inverter specs. The first step is defining our load. So as we did before. Now here we have lambs, air conditioner, Davy refrigerators as same procedure. But you can see the system is a little bit bigger than before. You can see we have in the system to air conditioner. To air conditioners. Number to each one of these conditions is 800 Watt and working for 4 h a day. So you can see it takes lots of energy compared to lamps and other loads. Now, as you can see here, the total wattage is 2,700 watts of our loads. And the energy per day, the same steps that we did before. Okay, we don't need to repeat the same explanation as we did in the off-grid system here, what we did is the same procedure with the power of each device, the energy, and then we added all of these system together. Now, the first step we will go over the second step we will size our panels based on our load. So we will take our energy again and multiply it by 1.3 as a safety factor, the same as we did before to accumulate for all the losses that are killed in the BB system. So when we take this value and multiply it by 1.3, we will get 71,717,100.60. What hour. Then we are going to take this value and divide it by the peak hour or the worst sun hours. Again, I choose my own country. In this example, we have in our country, 5 h is the worst beaks on ours. So the amount of power from the beaver manner is 3,432. What? And I'm going to choose PV panel similar as before, is that algae monocrystalline with 100. What? We will take this value and divide it by 300 to get approximately 12 panels. And we look for the nearest even number. Because it's an odd number will make lots of issues when we are connecting our panels in series and parallel. So we always look for an even number. So here we reach it 12, a balance of us, rounded ones. This is a bigger system as you can see, because we have large loads here. We have air conditioners that walk for 4 h, so they take lots of energy. And in addition to the refrigerator, refrigerator and other loads. So we have now selected number of panels, a power of each panel, and we also defined our loads. So the power of panels here which are going to produce is 12, a balance multiplied by 300, which is 3,600 watts. So here we will go to the hybrid inverter. Now, since we are going to connect to the grid, to that decision rate or to the AC generator, batteries, panels, overseeing connected to one device or one big equipment, which is a hybrid inverted. As you can see in this figure, it does all of this together. In order to select our inverter, we need some information that we obtained in the previous slides. Because the first thing is that again, the inverter power should be greater than the load total wattage, two pi to two pi bonds a t percent, similar to the oversize that we did in the off-grid systems. Why? Because if we e.g. to compensate for any future expansion in our loads or our PV system. So we have 25 or assertive present greater than solute, total wattage. So we will take 1.3 and multiply it by 232,000.700. What? We will get this final value. And we will go to the inverter social power again as we did before. So we have five lamps, five multiply by 60 plus z d v, which is one multiplied by 200, plus refrigerator. Here you can see four, which is the starting current of the refrigerator, multiplied by its wattage, which is 200 watts, plus four multiplied by the air conditioner. So it will be four multiplied by air conditioner. What is the air conditioner here? We have two air conditioners, and each one is 800 Watt. Okay? So four multiplied by two air conditioners, multiplied by 800. So in the end we will have a surge of power of 7,700 watts. You can see very large cells about due to the presence of air conditioner. So we need an inverter from that information was which we have gotten right now. Inverter with in continuous power of 2,900 mine. She worked and associate a power of 7,700 watts. Okay, so let's combine all of this together. So you can see that we have here in our system as alluded that we have here. So if we get back here, our loads are 2,700 watt, right? So 2,700, What is greater than 2000s? So in this case, we are going to use a 48 volt inverter or on line six volt in volt. So the inverter, what I mean by this is this representing the system voltage of the battery. The batteries can be either 48 volt or mine T6 volt, 48 or 96 depending on what? Depending on the inverter that we will find in some. Ok. So as you can see here, so the first step is that we have 48 or 96 volt for the batteries. We also need an inverter with a continuous power of 2990 watt, power of 7,700 watt. Now, not only this, but we have solar panels. If you get back here, solar power, solar panels, 3,600 watt. So we need to add this also. We have here BV Reynolds, 3,600 watt panels input 3,600 watts. The inverter must always stands as value. Also for the output, it should be give us this power and social power of this value. That batteries can be 48 or 96. Now we, when we combine all of this together, we go to market and social enzyme catalog for a hybrid inverters that can withstand all of these values. And as you can see, I have already added this value. So power of panels 3,600. So we can delete all of this. So let's go to this must. Must is a company for hybrid inverters. So I have used one of their inverters in as a design of this bv system. So you can see we have these different devices or different inverter. So as you can see here, Let's delete this. If you go here. The spot, each of these are inverters, 12,345.6 inverters. Now the force is three inverters are the first two inverters, sorry, two inverters or cleanser on the 24 v. So we don't need this too, because we said that our system is 48 volt or 96 volt. So here we can see this four inverters work on the 48 volt. So we will select one of these four inverters. Now the second step is that you can see here inverter, inverter output, you can see rated power and surge of power. And the waveform, of course a pure sine wave. So you can see rated power and social power. So if we get back here, you can see rated power required 2,990 and social power of 7,700. So the first one, yes, it accept it gives us a rated power required which is 2,900 and mine T1. However, if you look at the surge of power, you can see 62,000.12, but our surge of power is 7,700. So this one will not withstand the surge of power. So we will cancel this one too. So we cancel the first three inverters. Now we have this one, or this one or this one. Now, all of them are suitable. Why? You can see rated power for selves and walk. But our rate power is 2991. So it can withstand rated power and social power. Itselves on towards greater than our search bar. Okay? This one is also can be used. So all of these three can be used. But I'm going to use this one because it will be the cheapest because as red power increase, surge power increase, the more expansive our invoked or become. So, we are going to choose this one which is 4,800 watt. It's all done to auto social power and four cells. And what rated power? Now, let's then we're going to go down here. Go down here. You can see this one has Z suspects. You can see here is the battery specs AC input, AC input here representing the power coming from the generator. Voltage and frequency range. You can see 50 or 60 hz. And also it accept this, the voltage from the grid and the voltage from them. The generator. Okay, now why do we use this power? Because we use this amount of power from generator or grid to in order to provide electrical power to our home, our system. So in order to provide electrical power to our home, the loads in our home and symptom can be used to charge our batteries. You can see we have a solar charger. So it takes us apart from the PV panel and the charges, the batteries, the EEOC charges takes us apart from the generator or the power grid. And the charge about all of this are inside this hybrid inverter. Now we obtain the values that we need for the output. For the input, we are concerned of several values. Number one, maximum BV, open-circuit voltage, as we did in that of grid systems. And we also concerned with the maximum power point tracking range here and maximum PV array power here. Now why maximum PV array power? Because if you get back here. You can see power of panels 3,600. So we have to make sure that this value, this value here, exceeds the 3,600. So for cells and what it means it can with stand up to four cells and what coming from the PV panel. So here it is, correct. Now we have the maximum solar charge. Kansas is the maximum current that the solar charger inside the Zan inverter itself. Maximum currents that will be charge, that will be used to charge the batteries. We have solar charger that takes power from BB banner and the charge, the batteries. So this is the maximum current that this solar charger control. A current that's this solar charger can give the AC charger, you can see maximum AC charge or current 60 amps. So what does this mean? It means that the maximum currents ads are charged, are coming from the AC system, from the grid or the generator. It can give up to 60 and bear to charge the batteries. Now if you look at the rest of that data sheet, you can see that the maximum current will be 140 amps. It will tell you that maximum battery charging current, 140 amps, which is a summation of 80.60. Now we have to remember that this current, yes, it is a maximum, it's solar charging current or maximum AC current. But we have to make sure we have to remember something which is very, very important is that our batteries have certain, our batteries have certain charge current, depending on the data sheet or the specs. So we cannot use the ATMs biweekly. We have to make sure that our batteries can with stand as this guy, depending on the data sheet. Okay, Now, using this maximum solar charging current, we can select how many parallel strings. We have to make sure that the parallel strings short-circuit current as lower than 80 amps. Okay? Now here, let's just start the next step, the panel connection. So here based on these values, we can select the how many panels in series, right? Maximum PV array open-circuit voltage, and the maximum power point tracking range. Now remember that in the previous lessons of that design of the of grid system, we use this as value. We use the half of this value. We selected how many panels in series based on half of this value. Now why did we do this? Because we didn't have this range. However, we have now maximum power point tracking voltage range. So we are going to take the half of this value, half of this range. Okay, so we are going to design based on half of this range. You can see assuming the selection of the panel system voltage at the middle of the maximum power point tracking range of the inverse. So it will be hundred plus 64. You can see here, hundred and 64, which is a range here. Here, hundred 306464/2. So it will give us 97 volt, which is the middle of the maximum power point tracking range. Okay, So mindset one is the system voltage that we are going down based on it. Now what we're going to look, so we designed based on what maximum power point tracking. So I'm going to look for what maximum power point tracking. So in the off-grid, we said that we are going to take half of the value of open circuit voltage. So we selected based on open circuit voltage. Since that we have here in this example, the maximum power point tracking range. We are going to choose the maximum power point tracking value. So again, if you are designing based on open circuit voltage, is any overly choose as the open circuit voltage from the specs of the panels itself here. Okay? There's the open circuit voltage. If you are designing based on maximum power point tracking, then you are going to select as a maximum power point tracking value. So here 97 volt maximum power point tracking then only choose 1.6. So design maximum power point tracking divided by in panel maximum power point tracking. It will give us three or approximately three panels in series. Now to get how many panels in parallel with assembly divides a total panels that we designed before we said we are going to take 12 panels and divide it by number of panels in zeros. It gave us four parallel strings. So we have three in series for embarrassed. Now, we have to make sure that this series connection does not exceed. The open circuit voltage. So what are we going to do? The open-circuit voltage ends our adds a worst condition will be number of series panels, which is three, multiplied by open-circuit voltage of one panel, which is here, 8.9, multiplied by temperature compensation factor, which is from the NAC code. The worst condition in all its temperature, I will say 1.02, 20 Celsius degrees. So it will be three multiplied by the open-circuit, which is 38.29 here, multiplied by 1.02. Why you all on Wednesday? Because I assumed that my worst at temperature in my own location, 20 Celsius degrees. This is an example of, of course, you have to make sure you have to look for that temperature data in your own location. So we multiply by 1.0 to give us 119.034, which is lower than the maximum open-circuit voltage of the inverter. So if you get back here lower than this value, this one, maximum open circuit voltage. So our design for the series connection is correct. Now we have to make sure that the current does not exceed the ATM's like this. So we are going to use the same as we did before. The input current forms the panels will be short-circuit current, which is 10.07, multiplied by number of parallel strings multiplied by the safety factor k. So give us 50 amps, which is lower than 80 amps. Now we have to mention something also important to hear. If you find in the specs. If you find some specs here, maximum short-circuit current from panels or maximum input PV panel. You will use this value and those design instead of the ATMs, okay? Because it will reset things that amount of current coming from the panel. If this value is not available, just use as a charge current instead. Okay, so here is an extra step is sizing the batteries. Now we said we have a 48 volt system, so I'm going to use the EGM battery. You can choose any battery would like. Okay. Lithium ion, calcium ion, phosphate, nickel, cadmium, anytime you'd like. Anyone unfortunate we have discussed before. So I choose the AGM. Here I am bear our similar as what we did exactly in the design of the off-grid system. Total energy coming from saponins multiplied by how many days of autonomy, how many days at which the sun isn't available, divided by depth of discharge, which is 50 per cent. Since we are using AGM system voltage which is 48 volt. Since we have a large installation, multiplied by temperature correction coefficient, which is coming from the data sheet itself. So temperature coalition correction coefficient is 0. Point to mine from the graph itself. If you don't remember that graph, which we talked about before, and which we have a temperature versus the temperature correction coefficient from the data sheet itself. If you don't remember it, you can go back to Lesson two of the design of the off-grid system. So it will give us 794 ampere hour. How many batteries in series, the system voltage divided pi is a voltage of one battery. Here we are using an EEG and battery of 12 volt. So we take 48/12, it gives us four batteries in series. How many parallel strings it will be. As a value of the pair, our require divided by ampere hour. Battery gives us approximately four parallel strings. So our total batteries are 16 batteries. Now, this is a curve that I was talking about, that temperature in Celsius or Fahrenheit versus the percent of available capacity. So as you can see at 20 per cent, at 20 Celsius degree, Celsius degree, approximately 90% of the battery is available. Okay? So the connection of the battery will be like this for a series batteries. And for Paris string, you can see 1234 in series and 1234 parallel strings. So that series connection format 48 volt as a parallel connection for me, 205 plus 205 plus 205 plus 205, which is four multiplied by 200.520 ampere hour more than what we need. So our final PV system will be like this. We have three panels in series, as you can see, and three panels in series in each string, we have 12 abandons, 33333 CROs multiplied by four parallel strings form as US array. So each of the poster by negative will go to the combiner box, as you can see here, all gone to the combiner box. Then we will have final positive and a negative which will go as an input force. And let's zoom in as we did before. So if you look at here, you can see positive and the negative going into our inverter here. Inside it we have a soul or a charge controller, solar charged, solar charger or a soda charge controller inside the inverter itself. So it will take this two inputs and it will go to the batteries to charges positive and negative. Now at the same time, the inverter will take from the same two terminal, from the same two wires. It will take the electrical power and invert it into electrical power or AC power for our loop, it will invert it. Now another thing, it can take AC power from the diesel generator or ACM, but each one has its own input inside the inverter itself, one for the diesel generator, and one-fourth is that grid. Here. It will take them and then it will start a charging batteries. You cannot charge a battery or you can just bypass, bypass the power coming from the AC grid or the diesel generator and the start giving power to our AC roots, as you would like, you can do this or you can do this. And of course you can do that. Periodicity if you'd like to and take power from batteries first or panels or ECM. But all of this can be done inside the settings of the inverter itself. Okay, so we talked about in this lesson about the design of the hybrid PV system. We talked about a little bit, a little bigger, a little bit bigger BB system than the previous ones. It's considered as large installation system. And we have seen how can we select one hybrid inverter that will do several functions at the same time. 59. Helpful Notes Regarding Hybrid Design: Hey, everyone, let's have some help of notes regarding the design of the hybrid systems. Similar to what we did in of grid systems, we have to make sure that the sizing of the hybrid inverter or the current rating for the charger must be sufficient to prevent any kind of par loses. If you remember in this example, we had power of panels equal to 3,600 or 3,600 volt, and system voltage is 48 volt. In order to find the current that is going to the batteries, we will divide the power divided by the voltage. 3600/48 volt equal to 75 embers, this is the maximum current. Now, if we look at the dataset here, you'll see that the maximum solar charge current is equal to 80 pairs. So 80 pairs is sufficient for the 75 empire requirements. More than the required value. Now, during that design, you have to understand that this value Maximum solar charge current this representing the output of the inverter to the battery, but of the inverter to the batters, not the input. The most important part or since we don't have here any specs regarding the input regarding the input, it means that the maximum current is 80 pairs for this input and output. Maximum current, 80 pairs, Here for the batteries, same as we did before we have to make sure that the batteries must withstand the value. In this example, we have four barel branches. Each one will take 75 pairs, which is the value given by the charger controller or the inverter at the maximum condition, divided by four, which is a four parallel branches. Each branch will be 18.75 pair. We remember that from this instructions or charging instruction, that 20% of 205 is 41 pairs, which is greater than the required pair branch. If you don't remember, this is a configuration here. In each, in each branch here, we will have 18.75. Each battery or each branch can withstand 41 pair, which is greater than the maximum value. The design here is correct. I hope now you understand the design of the grade system and the hybrid systems. 60. Example Design of an on Grid System: Now let's discuss how toe design an own great system. Okay, so our on grid system is connected to the grid and also providing Bauer to our home. So the first thing you are going to do in the grid trite system we wanted to remove some or all off my own electricity usage. Okay, so I am someone who has a house and has killed what our and I would like toa decrease my own consumption off electricity from cigarette. So I build my own great tight system. So I take a power from the BB system and take power from the grant. Okay. In order to save some money. So how told design along great system. The first thing we are going toe date her mind or determines immensely usage off our energy consumption. Then we will calculate the daily requirement of four Kill what our or kill? What then? We're going toe defines the array wattage were required. Then we will select Azia Rae. And so is invert. Now, finally, we will have a sizing off the protection device. Number four has a section on our course of four discussing how to size the protection device. Now we assume that we have here and examine off my electricity usage. For example, on a on July 13 I consumed the 2109 3 kilowatt hour on August is value and throughout with that 12 months. Okay, Now, the first thing you are going to do is that we are going toe determines E on one daily average helm. How many kilowatt hour of how much kill what our I am consuming in one day. So in order to find the daily average, we will. Some all of these values, some mission off all the months is in kilowatt hour, divided by surround 65. So, by summing all of these values which will give us 18,485 and what it buys around 65 days in order to find as the average consumption kill what? Our bear one day which is 50 points 63. Okay, so this was the first step. Second step. We need to remember to selectors that'll the angle in our BV system remember that in the map and dizzy as a member to contend dizzy, approximate measured and the accurate message using Z degrees, for example, as we remember greater than at 25 degree or of 25 to 50 degree. We said that we will multiply it by a factor. Then add 3.1 degree. You will remember this from the lecture off Delta Angle and shedding Anil Sense. So we will find the tilt angle off our system. Using this missile, we will assume our system efficiency for all of the wires. Thean voters, Izzy losses in thesis See yr, ZZ pennants that mismatching between manners panels, Izzy quality or dizzy quality off sick and panels itself as I efficiency as the diehards and connections and all of this. Okay, all of this will give us a system efficiency off 77%. It can be large ones on this, but I will just assume the average value, which is 77% now. We would like to get their kill. What required from our BV system. Okay, after this system, so is the chicken. What? Our required four z load Ok is the skin. What require the four zeroed. So kill what? Our divided by the peaks on hours. Okay, So have here 50 points city 63 56 The violent boys are picks on hours of 4.5, which will give us 11.54 kilo. What? So this is the net power going toe the house. Okay, the net power going toe to toe the house without the efficiency off course. But remember that the bigs on farmers, We In a previous lecture, we had a a large map where we said as the pigs on ours for ear for every location. Okay, if you get back toe the brave, your slickster, you'll find bigs on ours for its location on the world like me. Now, considering their system losses, the power required from the BV system will be 11.254 divided Boise efficiency. So the net power required toe supply. Our house is 14.615 kilowatt. Okay, Now, we said at the beginning that the on grid will just remove some of the electricity bill so they're designed. Depends on my own budget or the space available. So, for example, I will assume that I will need toe cut 50% off my own pen. So 50% off see power required from the TV system will give US 7.308 Kill what require? Okay. So in this system, on great system, when we are chosing our inverter, we will choose any inverter hires and this value. So the one which is available in our market is eight. Kill what? And not 60 kill. What? Okay, so, uh, so six again. What? Or it can What? So we will choose the it kill. What? There is no seven kilowatt. Okay, so we'll chose. Ah, higher value. Which is it? Kill what? When I look dozy that a sheet off the inverter. I found that the value off the D. C and what should be from several 100 to 480 vote okay as a minimum in both surrounded and a maximum value of 480 d c. Voltage. So I should consider when I designed that several 100 a vault. Okay. As a minimum, import value does the invert. So for our design, we will not choose. Their critical value will just choose an average of value. For example, 260 evil. This is an assumption we can chose 787 140. Any value betweens this, But I don't want to toe choosy, highest or is a critical. I'm choosing a value between them for our system. So surround 60 vote, which is the input from the TV system. So that BV system should at least the supplies run 60 vote. So we have now at the front Panin Z maximum bars around that what Zeevi open said 27 vault and I short circuit 11.1 pair. So as the first step is that we need to find the number of the panels number of panels required is equal to zero power over the power off one panel. So it will be 24.36 I can choose 24 panels about it will give us lower power, then this. So I will chose the higher value, which is £25. Now the we need to find the number off serious parents. Okay, So the important thing here is that our inverter has a 760 vote. So we need our pennants to provide this value So we will take surrounded and 60 vault and divided by the open circuit off each off the pan. It's OK. So 716 divided by 27 will give us 13 born three, which will give us 13 planets. Okay, we can choose 14 or 13. OK, but I don't want a toe choose 14 so that their value should not be very high. Okay? Or according to on design now is the number off the barrel will be equal. Tosi, 25 panels over. Number off. Serious which will give us one boy in Toronto which is to barrel and strengths. Okay, so the new value off panels will be equal to two battle strings multiplied by 13 C response which will give us the 26 planets. Now let's see the new power Because we designed 25. We now designed 26 so 26. But the by bison 100 What will give us 7.8 kilowatt which is listens A inverter. Kill what? Which is eight kilowatt? Okay, so this waas that design off a known greatest very simple and easy. Okay, why did we choose here It kill what? Or hires? And this Because inverter is dialectic connected toe the BV system so we consider the m. But toe the in vote. Okay, Now you will find here is that this values can be also obtained by by the baby. Assess the program. Okay. And we have another section. Will we discuss that sign off grade and on grid system using ZB v assist. And if you try this and it uses 100 what to win seven vault and you'll find years at the design is okay and the same as the program, okay? 61. PV Energy According to Area: now how? Toe? Find dizzy energy off the BV according to our area. Okay, if I have an area which contains solar panels how don't know how toe defines the amount of energy produced by Zeze BV. So we have here are low called energy off their devi, which is killed. What? Our equal toes the area total solar panel area in meter square. What about by our core disease? Whole opponent yield or efficiency, for example, as remember that the mono crystalline, poorly crystalline Z hyper it and so on. For example, here's the efficiency can be according toe that a ship off the panel can be, for example, 16%. Okay, which is the n one average solar radiation on the Tilted Bannon's and shedding off course or not included. Okay, where we can find the edge as you remember that as the radiation Here we will goto this website which we used before, and we'll find the variation off the radiation across Z year. Okay. And you can find here an average of four z value. Okay. According toe. The latitude and longitude. Okay. Now the total area off course, it will be equipped with the area off one panel Martyr Blood by the total number. Very simple now is the performance. Racial represent Izzy losses, and it can be from 0.52 point online, so we'll choose a value off 0.75 Okay, that efficiency, as we said before from the table which we discussed before. Okay, in the election off selection off a panic. Or we can go toe this website with at the front that are, you can find this one hands at the front. Efficiency values for the BV panels. Okay, you will find this NZ provided slides in the course, Okay. 62. Design of Grid connected system using PVSYST: In the previous video, we designed our standard on system using BV says the program. Now we are going toe design our system using a Z be recessed the program. But now in a great connected system. Okay, so the first thing is that we are going to choose that Zain as before then great connected . Okay, Now the first thing is a project name. Okay. We named this product as Kairos. Whole lot one. Okay, now we will choose our site and meet you. Now I'm with choosing as the same site which I made before, as in Z stand alone system. Then click on. OK, now you have mood appoints a project to please see save Z seven before managing calculation versions. So our saves the project. Save again now please defines the plan. Orientation orientation. Now we said before that in our place, which we discussed is that the ah teldta angle should be certain degree. And as most should be zero degree. This is for my own country. All my own government care. Okay. Is this values therefore according to your own place? Okay. According to Z Longitude and dizzy actitud, you'll find that the values here will therefore, for the maximum value. But as you remember, that fourth e Africa or the other values in the large graph which we discussed before you'll find that the angle was between 26 Atto sort seven degree, as I remember. Okay, so now, as the as most, if you didn't understand it, this is the solar PV. When I imprison toe 20 degree, for example, you will find here that this is a vertical, okay, vertical and the angle between it and the West is 20 degree. Now, if I change it toe minds degree, you will find that Z fares off. The solar is heading. Throws the west or the west is perpendicular toe Z I BV panel. Okay, so the tilt angle and there's most just shows you the right or the optimum or the value specific foresee, place off the location or the solar panel. Now I will click on OK, now, system definitions. Please define that star power or available area. Now, here's the difference between the on great and off grid in the on grid. Now we need to define our system first you have two options. Okay. These are toe Bootsy plant power required from CB VI panels or right Z available area. Okay, you will see Is that Please define Xenzai it power or available area. So I will chose first to see plant power all chose here as with before as as seven kill What big power. Okay, click and own enter. Okay. Now we will find that Amazon message appeared to please choose a PV module as we did before . So we'll choose all manufacturers. All modules LG for example. Now we'll choose here and value for example we said here 230. What big like this one. Let's remember each panel sort of old eight points. Really? Let's check that at 200 inserted 250 would be cookie. So let's change it again. 150 would be cookie. So this one is 251 Peak 25. Walt, have moral point. Ok, so, um, now we will find that here. Please choose a inverter model. And the total power should be If I kill what as an optimal value or more. Okay. Source here that we are talking about a great connected system. So the power off. See, um, the inverter should be equal. Toe the poor off the great. Now, let's see. First, we are going toe chose. Okay? Is he available now in a single like SME, which is a famous company will choose an inverter, for example. Air five killed. What? Now we will find that inverter power is like the oversized. Okay, Now let's see why you will find here that the nominal BV power is seven kill. What? Big Maximum BV. Boras A. D c. Saw a 6.5 kilowatt D C number off inverters. A two number from yours. 28. So here it is, using at two inverters. Each is five. Kill. What? Giving us a total power off thinking what a c. Okay, so, thinking, What is the total power off the two inverters? Okay, so we need it is just hard then and seven. Okay, so let's choose for example, seven Kilowatt. Okay. We'll find your different versions According toe as the voltage is the voltage Easy in boat toes. E'm an inverter. Okay, Is a dcm boto the import, for example, we are going to choose the this one seven kill What? Surrounded 45 you'll see that the message disappeared. The inverter power here is equal toe the nominal BV power. Okay, so you have to remember that in the great connected system Z i BV power is equal toes the inverter power. But in the off grid system, we said that the power off the inverter as you have to remember power of the inverter Waas 25% greater Zen, the power off the road. Okay, so here's the inverter in the off grid system. One point with five multiplied by Z loot. Ok, but in the on grid system here, the power off the inverter is the same as the power off the BV. Okay, this is the difference between the on grid and off. Great. Okay, Now we will find years that which was an inverter one inverter seven kill. What is the operating voltage? And in both maximum voter 600 vote So this inverter can withstand and in body sees up to 600 volt. Okay, very simple. Now we will see that here Z m with yours in Syria's according toe. The design off the program 14 in sailors and the two parallel strings. Okay, now we will find here 14 months. Roberto Orci is 28 modules. 28 modules in case off a seven kill. What? Big? Same as we did here. You will find here in the off bread. We also add seven. Kill what? We off tend accurately. 28 panels. Okay, remember that in the example off the program off the stand alone system. We said that the power waas eight kilowatt. Okay, not seven. So now we will find here 14 in Sears and to impart. Now, let's see on other things. Okay, let's see. 14 in cedars means that let Caesar calculator. Okay. 14 in Siris. Multi blood Boise. Voltage off. Easy BV, which is going to five, will give us a 750 volt surround. And 50 volt is in the range off this inverter. 654 45 no. 480 World. This the voltage off the a total array or the modules. Okay. The taught on voters around that 50 which is in the range off the operating voltage off. See? Inverter. Okay. The also seeing a voltage off the modules or the array should not be Liz End surrounded 50 have 34 for surrounded 45. Ok, Now, um after Don't just We have done all what we want in this, uh, a window we would click on. Ok, since there is no message ears and everything is fine. Okay, Now we find all of them are green and you can do here adds e which is optional, adding z shading negotiating analysis. But in this case, you will have toe draw the shading in the installation area. And this is a complex. You need someone to draw Z shading in your own area on the TV so you can adjust these values. OK, but this is an optional thing. Their most important thing is the orientation system. And this is too important thing. Ok, now we click on a simulation, as we did before simulation. Okay. And the report and your fund here again, the same data. You will see that here we have 40 modules in Sierra's two parallel strings. 28 modules at 250. What? Beak for the unit and nominal power. The big power off one module. The ah normal power is seven. Kill. What big? Um, some details about the inverter operating voltage. The nominal power off the inverter is equal. Toe the power off the nominal power off the PV array. Okay. And some losses here. This system generates at 12.15 megawatt hour bear year. Okay, Uh, and years, the losses as before, I just want to tell you, Is that a seven kill? What is considered as a medium system or not? A very large system. A medium system just for your own home. Okay, so your own house or your own home can be power The pious seven kill. What big system? Okay. 63. Introduction to Water Pumping System and Steps of Design: Hi everyone. In this video we would like to discuss Zara solar water pumping system. This video we are going to discuss Z basics or the steps of designing zip Walter palming system, which is working by solar PV system or solar energy system. The first thing we are going to discuss the steps of design. But first, we have to understand that zeros are two types of bombing system. Number one is our traditional pumping system. And the second one which is BV bombing system, is that throw additional pumping system which is working by having some force by hand or by using a diesel motor, for example. Bv bombing system is by is-a usage of that solar PV panels provide power to an electric motor in order to operate zap pumping system. Now let us see that traditional pumping system, as you see here, as this is a traditional pulmonic system, is this bombing system is working by DC motor. We need fuel in order to provide motor, and the motor will operate. Then it will provides us z water by getting seawater or sucking water from the underground to field. Now, this one is also a traditional poem mixed system. This one, of course everybody knows what is this. We simply use this for Surat by moving it up and Darwin, in order to suck water from wheel or from the well, or from any underground source, underground source of water. Then the water will be sucked up board, then it will go out toward the water outlet. Now this one can be done by hand, by providing a manual force by hand or by using a motor. Manuel by using force rod or an arm. This is enzyme traditional farming system by using guy a diesel motor path problem of his ideas and motor or using z, these are motor is number one, it is expensive due to fuel usage because fuel cost is high. Number two, difficulty of obtaining a fuel, especially in desert areas. In areas which are considered as a desert or does not have any source of oil, then it will be difficult to obtain fuel required for z. These are motor because it will come from very far areas. So we will need transportation costs. Number three, requirement of xy periodic maintenance because any electrical machine or any machine working by these L or any type of fuel would require periodic maintenance. But Zach EBV bombing system, it is very simple how it works assembly. We have our BV panels, which it takes sunlight or irradiation from the sunlight and converts it from light energy into electrical energy. Electrical energy will go to a pump, a controller, or an inverter. In order to control this inverter, of course, has its own maximum power point tracking inside itself or the charge controller, it's inside itself. This inverter will control the voltage and z power going to z bomb, this pump, for example, an induction motor. This one will be controlled by the inverter, which it takes the power from the solar PV panels. Z bumpy here, for example, this is a surface pump because it is at the ground or at the surface of the ground. It will take Psyc Z Walter by using the mechanical force succ 0 to and from The Underground and or lakes or any, wherever or any source of water. Then it will suck this water and moves through the palm. And the goals to an overhead tank. This tank which is used to store water in case of we need it in any other time. Because of course, that PV panels will only occur during five hours or six hours of the day, according to the bx on ours, is then of course, from the overhead tank we will provide power to our ground level or our field, which contains our sunflowers, beans, rice, or whatever. So this type of IPV bombing system, AZ maintenance, you will see that the system itself is very simple, so easy maintenance. Number two, no fuel requirement. And the nano is why? Because of course inside motors or chore KPI for you all, it has a lot of noise and at the same time needs fuel, such as diesel or any petroleum. But this type of pumps, it does not require any field because it takes a z power electrically from z bound book controller or from the inverter. And it has no noise or lower noise. Zan Zi pump. Normally is, what I mean by normal is that solar PV panels, because it is silent as we know. It operates only during sunlight basins, of course, because we solar panels provide power and we don't have any batteries in order to store the power. We use the pump to operate during peaks on hours, which is five hours, six hours or whatever. We can depend on z groundwater. And instead of using water from lakes or redox or candidates, because the palm, it takes water from the under ground. Now how we can design this system, it seems like assemble system, but we need to identify some points which will help you understand more about solar water bombing system. The first step is number one, we need to calculate the amount of water required for field Beardy. We need the amount of water, how many meter cube require the per day? And you also need to identify that flow rate of water. Q. Remember that we have the flow rate of water can be meter cube bear hour, or it can be meter cube bear. Second, we will understand the Winwood u is meter cube per hour and the wind to you is meter cube per second. Number, sorry, we need to calculate z pi diameter, the diameter of the pie, which is going to be used from the underground to Bombay itself. We need to calculate is a TDM or total dynamic head. And you'll understand what does this mean. Also, we need to calculate Z bomb biopower. And finally, z panels require. Now let's see step-by-step zap vertices. Step was how to calculate the amount of water require the bear day. We need to calculate the amount of water required the bear day. This means meter cube per day. You will find here a table which shows you is that consumption for each type of land. For example, sunflower beans, corn, cotton, tomatoes, mango rice and itself. You will find that for each type of plant, you will find here is that consumption for each acre, meter cube per day. So z acre for each acre we have meter cube per day. For example, beans would require 16 meter cube or folder bear day for each one acre. For each acre, we would need 16 meter cube per day according to the area of our field or how many acres that we have. We will multiply z number of acres by meter cube per day. That meter cube here is 16. For example, for Zeppelin's, for cotton will be 22. And it says, according to the amount of water required. That is the first step. From this step, we will get to how many meter cubes are required per day. Why do we need this value? Because we would need it in next steps. That second step, which is flow rate of water or Q, that flow rate is the amount of water here bear hour, this skew, which is required in the second step, is the amount of water bear hour. But remember, amount of photon per hour or meter cube bear hour. This can be calculated by dividing the total amount of water per day, which was calculated from the previous step. We said that here we can get from this table and by knowing how many acres we can get as the amount of meter cube per day required. We have the meter cube per day required. We will divide this amount or meter cube per day by z bx on hours. Why? Because the flow rate of water through the palm and z pipes, this will happen during Z sun hours or during their beaks on our queue will be meter cube per day divided by his epics on ours will give us the flow rate. Bear hour. How many meter cube of water flowing beard each one hour. Now that sort of step, we have now calculated Z meter cube per hour zone flow inside the pipes, which is going to form z under ground. The two is that overhead tank. Now we have the meter cube per hour. From this meter cube per hour weekend, calculate the diameter of zap pipes. We can get diameter of the pipes by knowing the flow rate meter cube per hour. For example, assume that we have a 50 meter cube per hour. 50 meter cube per hour is between 3256.52 is at 50 meter cube per hour is between them. So what will happen? We will select that Nick has the higher you will find here is that for example, if we have a 50, then we will choose 56.5, which is equivalent to diameter of the pipes in inches, how many inches? It is equivalent to four inches. You will find that if our flow rate was 2.25, then it will be three of our four inches. If it is 508, it will be 12 inches and etc. So according to the meter cube per hour, which was calculated from the previous step, we can get Z diameter of the pipe required. Now, the fourth step is a calculation of the t-th or the total dynamic eight. So what does the total dynamic head representing? The total dynamic kit, representing the vertical distance which is traveled. The buyer is water from underground or Zao, well, to the overhead tank. Representing z at the vertical distance bluffs some losses. Now what does this mean? This means that the inflow of dynamics, this is related of course to mechanical engineers about we will have an idea and how to calculate the total dynamic head, or DDH, is the total equivalent height, is that a flow it to be ambit, taking into account the frictional losses in Zp, it is representing z equivalent height, z vertical height. This height from z point or the surface of the well to the overhead tank. So this is, this is the height require DDH blas, the losses which was occurring inside the pipes. Because of course, when the water flows inside z pipes, it will have frictional losses. So all of this should be taken into account in order to design our pump. This is steps is used the two and the ending get the design of z bond. Now is that DDH equal to the static height, blas static left plus the frictional losses. Static left is aesthetic left, it, which is a vertical suction lift. This distance is the height. Water will rise before arriving at z as op-amp before arriving adds up pump, also known as suction head. This is, this is the distance from that surface of that well into the entrance of z, zh a motor. So the distance from the surface of that, well, those entrance of Zappa. Is this representing a static left or suction lift? Second height which is required is a static height, aesthetic height is the maximum height reached in Boise pipe of Thursday, also known as this charge. This is the distance from here from the entrance to the point at which it will this charges or water or provides water to that tank. This distance is called z. This is George head, or sometimes called the static head. Now again here as an example, you will see that we have upon, we have our pipe going into a tank and we have another pipe going into z under ground. When the distance from here to here is called suction hit this distance. The distance from that entrance, obviously pi to this charge is called disaster static hit that charge head. Whatever is the case, you know that you will understand, announce that we just sum the distance here. Blas this height, velocity frictional losses. So the total dynamic kid, as an example, we have static 824 suction head to a point for friction loss is equal to 8.6 meter. So the total distance or the total dynamic head will be this value plus this value plus this value gives us 35 meter. Someone will ask me, Why do we calculate the total dynamic head? Because we need it in order to identify our bomb bus kilowatt or the horsepower. We now know is a static hit the suction head. But how we can calculate the frictional losses, that total dynamic equal to static head plus suction head plus friction losses. We know that the static head is the difference in height between the pump and the point of discharge from here to here, from z, from the point of this charging inside that tank. And the suction lift is the difference in height between that fluid or the surface of the fluid or CSF surface of that. Well, until the inlet of Z bump. That friction losses is the total losses sustained the Boise liquid as it flows from the suction pipe. Those are point of discharge representing Zeff frictional losses from that suction pipe, which is this pipe going through all of this to xhat tank. Now how we can calculate the friction losses, the frictional losses have a simple law. Remember that all of this z static head suction, head friction loss, all of them are in meter. So the frictional losses required is in meter. Now we have an ol for fluid dynamics. In order to get the friction loss is the height of frictional loss, which is required equal to 10.67 multiplied by saccule or follow a flow rate. The flow rate here, remember that the flow rate previously, we obtained it in meter cube per hour. But Zackie or here or the fluoride here will be in meter cube bear second, this is a difference between them over c or a certain costs constant to call it z has an Williams Coefficient. All to the power 1.852 multiplied by z length of the pipe in meter over z diameter of the pipe, which we obtained before. Tuesday power 4.87. Zackie, here, flow rate in meter cube per second. D is the pipe diameter in meter, L is the length of the pipe. F is the friction factor. C is hasn't William coefficient that c can be calculated. We know we can get the length of the pipe by knowing is a distance of the pipe or does the existing pipe, or by measuring the distance from z well to the discharge the tank. We have the diameter which we calculated before, the diameter of the pipe in inches. We convert it in neater. We know how to convert this. We know how to obtain the diameter from the previous steps, the ICU, we know how to calculate it. We will get 0 meter cube per hour. We convert it into meter cube per second by dividing by 60 multiplied by 60. Remaining thing is C. C depends on r Pi of material. If the material is BBC, then we'll lose a 150. If it is semen, we will use 140 if it is a copper, 130 and etc. So according to that exam material of the pipe, we will take the design see now is that Nick is step is the calculation of Z. Pump has power in kilowatt. Now is the power of xe bomb required for all of this would be equal to 0.02705 multiplied by total dynamic head. That's why we take all of the previous long step in order to get settled on dynamic eight multiplied by z q, which is in meter cube bear hour. Remember the units meter cube per hour in queue here. But that DDH we use the meter cube bear second divided by the efficiency of the pump which is available in the market. Ddh in meter, Zach you in meter cube per hour. As an example, for this, we have a depth of z equal a 100 meter. We have the height of that container, which is the overhead container, ten meters. Efficiency of the pump available or Zomato or equal to 80%. Assuming five hours of sun, peak hours, amount of water required equal 20 meter cube per day. This is a small example. So in order to get that dy dx is equal to z depth of the well, which is from the surface to z, which is a 100 meter plus Z height of the container itself, which is ten meters. Velocity is F friction losses. Now for simplicity in this example, we'll assume that the friction losses equal to 5% of the total height here. The height of the container blesses the depth of the weird. This is just a for simplicity. In Xanax, of course, in Xilinx, the video, we are going to have a practical example and it will get each step by details. This is just a simple example in order to understand how we can get z power. Bi is this will give us 115.5 meters as a PDH. Now how we can get that Q, is that Q here given 20 meter cube birthday. So in order to get z cube per hour, we will divide 20 by five by five to convert this a meter cube per day, or meter cube per hour by dividing 20 over z is on ours or does the peaks on ours? We have q, we have DDH will have the efficiency of 0.8. We can get a z power, which is 1.57 kilowatt. So this is the power of the pump required. Now with an extra step is that we need to get a zipper. Nice, of course we need an inverter and then we will need the penance. The inverter power will be equal to z power, as we will see in the next video. The power here will be equal to this one or larger. Now Z panel power required, it will be equal to output power entering Z pump or z power of the pump, divided by its efficiency of the inverter. We calculate a Z power of z pumping kilowatt. Now we get the power input to the inverter from the solar PV panels. Power in both Tuesday inverter from their BV equal to z pump power, the output power to the bomb over the efficiency of the inverter. In order to get this power. Let's type it. This is the power of the pump B bomb. We have the inverter here will cause some losses. So in order to get z power from the solar panels, we will have power panels would be equal to Z B of z pounds divided by the efficiency of Z inverter itself. Dividing these two values, we will have finally, power of solar panels. In this video, we'll discuss the steps are required and the types of solar water pumping system or a water pump mixes them. And the words causes steps in order to design this system. Now in the next video, we are going to have a practical example with values. We have a field with a certain type of plant and have certain amount of acres. And all of this we will get finally, is a complete design. 64. Solved Example on Solar Pumping System Design: Now let's have an example on czar bomb being sustained on how to design a solar pumping system. The first step where we discussed that we have a project here. We have a farm working with pompous or breathing with diesel fuel. We have already bombers which is working. We're using diesel fuel. Now in our system here we would like to change is this diesel fuels or these motors with BV bombing system. So here we would like to change his traditional system into BV bombing system or photo-voltaic bombing system. We have here is given inside our place or the allocation. We have the depth of the well equal to 40 meters is the height of 0 container which contains a Z Walter equal to seven meters. And feel the area, the area of Z form itself where we are going to provide water equal to 30 acres of mango. We have 30 acres of mango. We have the depths of Z. Well, we have seven meters above the height of the container. And we would like to get Z system or solar BV bombing system. Remember that we said that we, at first step, we need to calculate z amount of water needed per day. Here, xy given is 30 acres of mango. First we take z mango, which is Zell type of z plant. And do we see how much, how much meter cube or volume required the bear they you can see here in Zim angle, we need 40 meter bear day, meter cube per day for each acre. You will see that Z mango is 40 meter cube bear day for each acre. Adds beginning we have requires a mango requires 40 meter cube per day for each one acre. We have in the problem itself, we have 30 acres. It would be as a total amount required, the birthday would be equal to 40 multiplied by 30 acres, equal to 1100 meter cube bear day. This is the amount of water required for each day. So the second step we need to identify is an ICU or flow rate of water meter cube bear our assuming z number of pigs on hours or five hours. This is according to what? A coordinate Tuesday allocation of your own form. Remember, in previous lectures, we discussed how to select or identify is that beaks on hours of allocation. According to ZMapp, given ends of slides before and according to the Global Atlas and different methods. Now, assuming that your location is five hours a beak sun hours, It's the amount of water or as a flow rate, meter cube per hour would be simply total amount of water, which is 1200 over x0, x1 hours. So Q or the flow rate per hour equal to 1200, which is the total amount of water required the per day divided by the number of hours or without Sun Hours equal to 240 meter cube bear our second step. Third step is calculation of the pipe diameter. Remember from our table, large table we have here at q or is our flow rate is 240 meter cube per hour. So we need to select this API, which is used to take this amount of water. Two hundred and forty, two hundred and forty is between 240 between two hundred and twenty six hundred and fifty three. We said before is that when we have a value between two values, we select the Z higher diameter. The higher diameter of the pipe is ten inches. For 753. Q or the flow rate is 240 meter cube, which is between 226753 from setae was a next higher one is 153 meter cube bear our diameter would be selected is ten inches. Force. One is a calculation of the t d H, or the total dynamic height. Now remember that the total dynamic height is equal to the static head plus suction head plus the friction loss. This static head bulb suction head is the mission of distance from ours at depth of the well and The height of the tank. As a static head blows suction head is equal to 40 meters, which is the depths, and seven meters, which is the height of the tank, which is 47 meters. Now the remaining thing is a friction loss. Now we said we are going to calculate it exactly in this lecture. Is friction losses is equal to 10.67 multiplied by q in meter cube per second over C has an Williams Coefficient to the power 1.852 multiplied by z lens over z diameter in meter to the power 4.87. Now, assuming that c equal to 140 is a C, which is hasn't William coefficient. Where did we get it from? According to the pipe material. We said that we have a form which have a system already operating with diesel. We see what is the material of this pipe which is used. The code exists, we are going to select that design coefficient to see. As an example, we are assuming semen, which is 140, and the length is the length of z pipes used. You can measure it or assume it or an install it inside location and see what zillions of it. So that ends is 50 meters. Zach you or Zeff low rate per hour rate not return rate only per hour equal to 214 meter cube per hour. And here you will find that the rate is Q equal meter cube per second. We need to convert the Z, our 2 second Z conversion of our 2 second. Our second, we multiply by 60 multiplied by another 60, which will give us 1600. This is to convert our 2 second in order to two roses, we need to divide by 60, multiply by 60 because our is in Z lower denominator. So 240 will be divided by 10,600. In order to convert, these are meter cube per hour to meter cube per second. This will give us 0.0667 meter cube per second. Now Z diameter of the pipe in meters. So it will, because we need it in this equation in methods. In order to convert from inches to meters, we will multiply each one inch. One inch, one inch equals 2.5 centimeters. Each one inch, if I have 2.54. So by using this relation, we can convert this at ten inches to meters. That ten inches will be 0.254 meters. This value. Now we have the diameter D, we have the length. We have a Q meter cube per second, or 0.667 is I, c is given as 140 according to the material of z. Then we can substitute in this equation, the friction loss will be 0.297. By substituting is that total dynamic head equation, DDH equal to 47, which is Z height of z suction head and Z height of z tank, 47 meters plus losses inside z pi 0.297 give us total dynamic ID of 47.297. Now, the power in kilowatts of z bar z problems and extra step, or 0.002725 multiplied by t d h multiplied by q in our ovaries, the efficiency of the pump. Now assuming that the total dynamic head, which is calculated now equal to 47.297 meter q, which is the amount or the flow rate per hour, 240 meter cube per hour efficiency, eighty-five percent is the power required will be 36.39 kilowatt. Now this is devoured by substituting in this equation, this is the power of the bomb. Now, of course, when we buy any motor or any bump, remember is that we buy it in horse power. We need to convert these are kilowatt into horsepower by dividing by 746 watt. 11,790. What divided by 746. What gives us how many horsepower required, which will be 48.7850 horsepower is X1, which is available. 50 horse power is the power of the bomb given required for this operation. 50 horsepower in order to convert it again, two kilowatt, because our BV banners in kilowatt, it will be a seventy-seven point three kilowatt required as an entering power to z. Now assuming an inverter efficiency of 85%. So the inverter power required will be or their amount of balance required and the inverter power. And we'll understand why 7.3 is the album to the prompt from the inverter. Divided it by the efficiency gives us 43.88, which is nearly 45 kilo. What is the balance of power required is 45 kilowatts. So 45 kilowatt is the power produced the advisory panels, which will be entering is the inverter. By having an efficiency of 85%, will give us nearly 38 kilowatt. Higher values answered 7.3, because we selected higher inverter, 45 kilowatt. So z power produced will be a little bit higher. As the panel power required is 45 kilowatt. And the actual power required for the motor is 44 kilowatt entering from Z panels. Now anyway, in order to select as the inverter, we now understand that we need but non-power 45 kilowatt according to the efficiency, which is 85%. And the outward 37.3 kilowatt Z, I will go and get to Z motor. Now by going into solar pump inverter implications, this has different modules or models for solar pump inverters. You will see that here as an example. 1500 watt, 18 kilowatt, 22 kilowatt, and etc. What does this number represent? This representing Z maximum output power, which is 30 kilowatt or seven kilowatt. What is the amount of power required? You'll see that here, we need certainty 7.3 kilowatt. The nearest one is 37 kilowatt. This one, which is close to the required bound. You will see that here. The adopted bomb but motor is our adopted, my bumper motor related borrowed kilowatt, 37 kilowatt, and our run a search 7.3 kilowatt, whatever it is close to each other. So set the seven kilowatt ends at rated voltage at which the motor will operate from surgery at volt, 440 volt as a line to line voltage between phases. Now you will see that t is at recommended BVM TO power for this inverter, 45 kilowatt b, which is the one calculated here. 45 kilowatt big entering the inverter. But reducing assert the seven kilowatt. You will see here is our maximum power point tracking your voltage from four hundred and fifty two hundred. So this is the range at which our inverter will operate in the maximum power point tracking values. We need to make sure that our design for the EBV is in this range. The maximum DCM both from the panels to the inverter is 850 volt. Rated current, going into the inverter is 71. And bear. Now, we need to design our panels according to these values. So we have to make sure that the voltage or the balance in series does not produce a voltage higher than a 100 or 250. We have to make sure it is in this range between four hundred and fifty, two hundred. We have to make sure that the number of arrays does not produce a current larger than 71. You'll see that this one has a range, but this one have a constant value of 71. This is the rated. In order to make it very simple for us, we will design according to the 71 and bear at first because it is rated, we can not exceed it. Now as an example, we have a panel. Here. We have a bundle of 245 what? 250 watts, and its efficiency. Maximum power voltage, maximum current, open-circuit voltage, short-circuit current. Now, we will choose, for example, that 250. What does this one have a maximum voltage of 30.53 volt. This is a voltage at maximum power 0.19 and bear, which is the current at maximum and bear. Okay, As I'm at maximum power, which is at 150 watt, 150 watt or ZigBee power is produced when having 3130.5 city volt and 8.19 and better. Now, we will use at 150 watts, so 2.53 volt and 8.19 and bear. Now is the number of banners that required is we need to remember that we said we need at 45 kilowatt BV in bulk power, 45 kilowatt divided by the power of y1 Bennett, which is 250 watt. Give us what gives us 180 panels. This is the total number of banners that required about a 150 watt to reduce the effort of 45 kilowatt. Now, rated current is equal to 71 and pair. So this is our rated of here. 721 is the rated input toes a solar pump inverter, one-to-one and bear. So we can get xA number of arrays equal to number of parallel strengths or number of parallel lines equal to 71 and bear divided bys and bear of each band at 8.19. So this will give us 8.66 or nine. Now, so do we chose higher or we showed the chores that lower? We will choose the lower y in order not to exceed 71 and bear. We will choose an eight arrays, number of arrays. Arrays, number of banners in each triangle would be 180 panels over z. Eight arrays, parallel strings give us 20.512 or 23 patterns in each string. So 23 banners in each strength and eight burly strings perform is eight arrays. And, or number of parallel strings, not number of arrays, number of parallel strings. All of this produces an array. Let's just one. Let's correct it now. This is number of strings. Strings. The number of strings is eight strengths in battle. And each string has 22.4 or 23 because we go to the higher value. And I will tell you now why is that 23 panels in series give us voltage of 23 panels multiplied by z voltage of each panel, which is 30.53 volt, give us 702.2019.19 is in the range of this one. Remember that the range here is from four hundred and fifty, two hundred, seven hundred is in the range of the maximum power point tracking the voltage. Now, we have at 23 strings, 23 panels in series, and we have eight parallel strings. Now someone will ask me how does this look like? You will have one panel and two going at 23 balance. 23 is this all of this is 23 panels. Panels give us what gives us 702, 0.19 volt. 19 volts. Now we have how many embattled? We have 123 and parallel strings. Parallel strings, string, this will produce a current, or the current will be multiplied by 8.19, which will give us nearly 6464 and bear. The input power is what does the IMO power is 23 panels. Multiply it by. Let's use the reason 23 panels, which is number of C or as strings. See it as panels in one string multiplied by eight parallel strings. So 23 multiplied by a barrel strength is multiplied bys at 150, which is z power, maximum power of one panel, give us what gave us 46 kilo watt. So all of this will be in the range of that wind to hunt. This range is that voltage is in the maximum power point range, and the current is under the rated value. We should make the current lower than which is 64, lower than the rated value of 71 and Bear power here, or does that BV orders that solar inverter here? Well, step-downs are 46 kilowatt to power require the Forza bomb itself, which is 37 kilowatt. So remember that the inverter here or the inverter steps downwards, the voltage values suitable for the motor. In this video, we discussed the how to design a solar plumbing system, how to select the bomb, but kilowatt or wholesale power inverter selection, Z balance required in our system. 65. Design Of Off Grid PV System Using Excel Sheet : Hi, everyone. In this video, we would like toa design our BV system. We have year an off grid system and would like toa design it using the Excel. So fund years that we have a sheet off Excel. You will find here the loading, the loading, our the components which we have in our system, such as the microwave washing machine and so on. Their powers there on bears, their daily use and their daily energy consumption. And you're falling here, Z Bannon's the battery banks and dizzy wiring capacity or the cable sickness or the millimetre square off the case. Now, if we look at this sheet alone first, I would like to tell you that this shade is not mine. I got it from online. Andi. I wanted to share it with you. Okay, the owner off the street, It's called Antoni on Cartwright. I think I pronouncing his name correctly. So what does this shed contains? The street is yours. Little designs that solar PV system. So at the beginning, you will find here the name off the equipment or the components inside the home. For example, the PC, TV, microwave washing machine, freezer, fridge and so on. And for each off these you will find that power. Okay. I bought here the amount of power in what and how much I'm using it daily in our. So as an example, we have here actual creator which you convert dizzy number of minutes to our as an example . If I bought here 60 then it will be one hour. If I would hear certain, then I would know that Or 0.5 hour if I bought, for example, two minutes, it will give us or point or three hours. Why? Because I won't like toe substitute in hours here. Okay. So, as an example of the power for the microwave 1250 and I'm using it for all goingto eight hour, which is equivalent Ato some minutes here. Okay, Now this microwave, when I you will find here the hour and z power. Now you will find years that we have here something which is called the domestic voltage. What does this represent? This is representing the operating voltage off your own A C system. So, as an example, we are operating at 230 volt. So you will find that here, Z and bear is calculated automatically. Boise program. How you know that the power is equal toe the voltage multiplied by the current. So we have the power which is 1400 divided by Z voltage which is 232 100 search the power over. The voltage will give Ah 6.8 which is nearly 6.1 AM Bear or fund your 6.1 and bit. If I change this one 1500 you'll find your 6.5. Okay, So that I'm very changes automatically according toe the value off power and as the voltage given Okay. Now, after boating all of our loads with their equivalent power their equivalent number of hours per day And as a program automatically calculates the currents here you will find here that the daily energy consumption for each of component as an example the consumption here or energy consumption is in what our so the what Our is equal to what the power multiplied by the time the energy equal to the power multiplied by time. So as an example, is the first component 1450 multiplied by the time which is open toe. It will give us 116. What? Our okay? Similarly, here is this one multiplied by this one. Give us the amount off. What? Our So from this body adding all of our components, we can automatically get Z. What? Our for each off our components. Then you will find that the program gives you the total daily consumption. In what? Our This is the consumption Bear day in our home. Okay, 2200 on 21. This is a total What? Our inside our home. Okay, So where did we get this value? Assembly? We something. This paralysis, Poulos, this or the submission off all of these values Give us that 2221. Now we will find that this is the net power or the net energy reaching our load. Birthday. Now, after adding the loss is off the charge controller, we will have 2468. And by adding Z losses in battery will have 2742 and my adding Z losses in inverters. Then we need 3047. What? Our This is required the power from our BV banners. Okay, there's the import power to our system. And is the import energy to our system 3047. What? What? Our This is the inbuilt dozy system and after going through the inverter will have some losses, batteries on losses and concerns you control some losses and the finally we will have 2221 . So now this is the energy required. Now, as we remember that we said that the in the off grid system when we selected the invert aerating way some all of the powers If you get a Z submission off all of the powers here, the submission off them will give us 30,575. This is that many Mom invert aerating by multiplying by one point toe and or 1.3 will give us a better optimum rating for the invert. Now we'll find that IFC inverter efficiency waas 90% then is the actual invert Aerating will be is re 1006 100 Want Okay Now you will find that Z What did you hear is depending on the total power and the closest value is 3600 as a value. Now we'll find years of efficiency for the inverter, which is assumed as a 90% or the bending on the data sheet. Now, as an example, if I changed it, look at this values. If I change just as 85% you will find that the energy now required from that BV system is now higher. Why? Because our inverter efficiency waas lower now or is lower now. So the inverter is suffering from more losses, so we need more or higher in both power. So if we change this back toe 90% you will find that the power required from the BV system Okay, the energy required from BV system is 4 3007 lower then before. So now we have the inverter we have as the inverter according to Z total wattage, which is something here. And the actual rating is calculated automatically by the program and the efficiency which will affect our losses and our selection for pants. Now for the ember drone, Boise and Verte, or the Bank Bank here representing the battery banks, you will find that this occurrence will see it later. Where did we get this values now, we're going into the other terrible 40 or other sheet for the panel. Banks, Z panel banks here representing Z panel. Look, Bank One bank, bank number one, as an example, is representing a collection off one or more panels wired in series. So bank number one, it means that we have a group of panels in series. We can say that bank number one is considered as a strength. Okay, so a grope off string connected in series or a group of planets connected in series forming a string. Now we need you will find here that the for this two panels. Okay, we said that we need a power. Get back here. We said that we need are what I want Equality Cities House on 47. So the first thing we're going to do is that we need to add that daily sunlight. Our So how much is our son present? Through the day? Now? We assumed at two hours. Okay, you know that there are hours during winter and hours a during summer. We will take the average between them. You can assume that five hours as an example, but for this example, we assumed it is too. Okay, now the next step. We have two hours as a daily sunlight so that daily energy produced from our system here is we chose at all banks. One having a voltage 120 and battle to it. Another 1 120 Okay. Each bank here representing once drink battle to each other. So this is stirring having 120 volt and 7.43 am and its energy for this bank or this group off balance to give us not energy, it should be easy. What? Or power 892 says this is about? Okay, let's correct it. Ah, what? So this is the maximum power off dependent maximum and bear off the panel and the maximum voltage, remember, that is the maximum is at the maximum power point. Tracking value Okay, is the maximum about going to tracking the value which give us the maximum? Our power this is does not represent is the short circuit current and this does not representing the open circuits. This value and this value is the values or voltage and the current, which produces our maximum output power. Now as an example. If I change this to 60 Okay. Let's see what the changes here. 60. Okay, you'll find here that total power, which is the voltage amount of blood by current status. Tomato blood by 7.43 Give us 446 and your friends as a submission Off to power. Give us total power off. 890 to this is grounded 46 plus 446. So this is a total power. Total current is 7.43 plus 7.43 since they are in peril. So we'll give us 14 point tonight. Voltage is the voltage between them senses er barrel. So they're vaulted. Will be the voltage off them. 60 vote now You will find here at two hours. What happens here? We need that amount off daily energy produced. So we have here Theatre. Total power. Okay, let's really this ate mine to this is the total wattage and the mater blighted buys the time, which is two hours. Okay, so when this ban El's adds the maximum power exposed the toe two hours off sunlight give us a total off. 1784. What? Our is this value? So this value is the amount off daily energy produced. Okay, this value is the energy producer from someone. And now let to get back here. You'll see that the required is 3000 47. What? Our reduced from our panel. So what we can do is that we it changes the voltage or we get more current. Okay. As an example Here, make it back. 120 will find that the energy produced as the total wattage is 1783. And this value wanted blood by to give us a total What? Our off 7500 statistics. This value is off course. Hires ends this value. Now we will find that's a charge controller. Efficiency from the market depends off course, 90% as an example. If I changed it toe 80% like this good back. You will find that the value off the energy required Increased. Why? Because more losses are in Georgia controller. So 3400 make it 90% as an efficiency. So it means that we need lower What? Our 30,000. What? Our Okay, So that 10% lower efficiency. Overcharge control cause Dizzy He required what? Our from the PV panels. Ato, be increased now for the current. Here is the charge Control current. This is the total current produced out from the charge of controlling A to Z batteries. Okay. And this is the bank Ambridge. Okay, so this is a bank Ambridge here representing Dizzy current off one bank. Okay, this bank which is connected toes that charge control now this'll current. Where did we get it? From the battery banks. So we selected our panels in order to satisfy Z What our required from here this what our and we selected the inverter According toe, the total power or the total water Ge now going to toes assert sheet for the battery banks . You will find that number one. We selected that here you will find a small details. Here's a bank's h a banker presenting to bank number one representing a group of patterns in Syria's and each off this representing five banks in battery. So, as an example, we selected a battery. Its efficiency, 90% isn't an example. Depends on the batter itself and the days storage required this Is that similar to? With the days off autonomy. Okay. And how many days do you need this battery, Toby? Overrated. As an example for one day without with the presence off, son. Okay, so it means that I would like to satisfy my lord for one day. So what does it mean? One day? It means that the energy required is the total consumption. Okay, My own. What? Our required bear day is 3047. So the battery banks should have What? Our off 30,047. Now, since we need as 3047 as a what? Our So what are Z capacity or dizzy and bare? Our required. So if I chose here at Banks, you will find your Grove Banks number one as a 70. Okay, let's delete this and the leads us and see what will happen. You will see that the programme tells use and the energy required in what? Our histories Hours on 47 This is a consumption daily and the energy required in a bear our which is obtained. The boy getting more betters you'll find energy required. Is sexist history on bear out. Okay, so this and bare our What does it represent This representing Z What? Our after the discharge rate. So what does it mean? Your fund Years at the battery again. The battery selected having at this astrologer it off 20%. What does this mean? It means that I can This a charge of my battery upto 20%. I can use only 20% off the battery. So if I have how 100 bare our battery, I can you use only 20 amber battery, 20%. Why in orderto have more lifetime for this batteries? Okay, this value can change from 10% as you see to 50%. Now, as an example, we assumed a 20%. So that capacity needed here in this case is 717. This is also calculated Boise Excel sheet. So what does this mean? Okay, going back here 717 and bare our if I have a batteries off 717 like this and the multiple and only used 20% off it so or go into too. This will give us a required on bare our for our system. Sickest is 3.4, so six assists. 3.4 is the ember. Our equivalent to was this what? Our cities Hours and 47. So we need a capacity off this and discharging it off. 20% in orderto finally get 63 which is a required and bare our for our system. Now look at here. So this if I have Citibank's off 70 then the capacity required will be 210. Okay, this is the capacity equivalent to this spring. About 210 illicit resents our under 17. Now, if I added another one, there is a total 280. Another 1 70 That daughter 750 which is greater than that required the capacity. So, sir, 150 multiplied by going to to using 20% off. See battery. Give us a 70 on bare our, which is greater. Scents are required from excel sheet. Now, what is the difference here is that the voltage here can change. We can choose that. Well, vault 24 volt search. Six vault or 48 volt. Now, as an example, What will happen if I changes the voltage? Okay, So the voltage here is 48 if we get back, you will find here that zee going back to Z a charge controller, you will find that the battery as the Mbare required certain 7.2. Okay, so this is the current capacity required by the charge. You don't charge this batteries. Now if I lower the voltage 24 volt. Okay. Making Z have altered jerk wad 24 volt. If I change, it's the voltage. You will find that the capacity in and bare our is higher. Why? Because as you remember, that the power is equal to the voltage multiplied by C current. So, in order to provide the same power at a lower voltage, then I need more current. Okay, So by reducing the system water, I would need more current. So going back here, you'll find that the charges of control Mbare required 74.3. So this is a very high on bear. So instead, off using this weekend, increase our system Voltage 48. So it finds that Z capacity required decreased by half because the voltage doubled. So the current the required is lower. Okay, now, if I change it toe mind six Vault 96 a vault you'll find that Zika bastard required now is lower. And you will find that deacon and required buys a charge. Control is now lower than before. So using higher voltage off the system battery will cause the current required for the charge of control Toby lower. So I will make it 48. Now we have our butter. Is we selected the weather? A suitable foresee capacity required at the 20% discharge rate now going to does the wiring . Now we have the soul or cable it or to control inverter battery bank. And they're impair NZ cable sickness. Minimum cable sickness required. And you will see that here estimation assumes a two meter lengths. Gable maximum. Okay, this is the maximum lens for the cable. If it is hard and would need a higher cross sectional area, why do does the voltage drop now? What is a solar cable? If I get here, you will find that this is the M Barry. Your solar cable monster carry forms the panels Atos, a charge controller. So this from the panel's does the charger control. So going back to the panels, you'll find that the total current off parents together is 14.29 So the cable should withstand this value off current from the panel's towards the charge controller. Okay, because we know that the solar system is connected to or the PV panels are connected. Toe Z charge controller. So this is the from solar cable toe from solar panels that charge control and they will find the years that many month cable sickness every millimeter. This is calculated by the program automatically forces charge concerns. The total current outside from the and George contrasted 7.2 showed withstands the current off the battery certain 7.2. So going back to the batteries charge controller current is 37 point. So this is the current absorbent Boise batteries. Now, As you see here, the total power is 17 783 1783 divided boys, the voltage off the better, which is 40 involved. This is the operating voltage off the battery. Give us a current off 37.15 okay. Or 77 point toe. This is the current which is drawing by the charge controller. Ok, Is the power over the operating voltage off The battery will give us 37.14 5 as a current draw. A win by our charge controller. So going toe the battery banks here we would need the wire from the charge of control towards the battery bank Books which contains is the connection toe all batteries. So does stand at least a certain seven going to toe. Which means we need a cable off seven millimeters square Now for the inverter for our inverter Here you will find this cable is from the battery Bank books A to Z inverter. So we'll find that this value going into Z inverter actually involved a draw Ambridge or the bear 75 being where did we get this value? I will tell you now. You'll see that here we have the rating off the inverter. 3600 divided boy, The senses This cable is connecting from C batteries. So the inverter So the maximum wattage in Potosi inverter divided by the voltage which is 48 pieces of all technologies entering Izzy Inverter. So we need a 75 Mbare for the inverter. Okay. The cable from the battery center to zing on Z and voter itself for the MBA toe the inverter. Now we will find something here that 75 we have five Burrell battery banks so divided by five. Give us a 15 and bear for each battery bank. So going here, toe the wiring 15 and bears. This is the at leases and bear from the battery does the battery box. And this from the Battery Bank books is a total better or the as if it was a song Junction books Who was the invert? So it should at least 75 AM bear And this 1 50 number on this is the equivalent cable sickness. So this waas an excel sheet in how toe design I believe a system using it. I will provide you with this excel sheet inside Z resources for this video. 66. Single Line Diagram Of PV System And Selection Of Fuses And Breakers : Hi, everyone. In this video, we would like toa learn how toe draws the single line diagram for a BV system and how to select Izzy cables and diffuses. Okay, so we discussed before everything about solar energy, including design, including their protection off the BV system. Now, I would like to show you a single line diagram in auto cad and I will give you this file in orderto edit it for yourself. Okay, So, first, before we begin going toe Z or to get, I would like to discuss the selection off the cable according dozy current. So we said before that the selection off the current the I already cable itself depends on the current. So we said that be before that we selected defuse. At first we said that if we have a system, then we get the short circuit current and the multiplied by a safety factor off 1.56 This is at 50 degrees Lazier's. Now, if we have a current for example, 81.84 as a short circuit ray current. Okay, so this is the current going out from the array, so we multiply it by 1.56 according towards the stun guns. Now, this will give us a value off the current equal 127 and bear. So this value off current should we should get a fuse which is equivalent to two. Is this value or higher? Then we select a cable, which was a stand. This is value or higher than the value off use. Okay, so we first they take that short circuit current and the multiplied it by 1.56 as a safety factor, as we discussed before. And then we get the maximum current 1.56 months of blood by the short circuit current from C R. A, which will give us a total current off 127. Then we will get our fuels according toa this value. Then we can choose our cable. Now, as an example, if we have this table at a 50 solicitors degree, okay, we assume that the temperature off the scale is at the 50 degrees leasers. Now, this values off the current rating, as you will see next. Okay, When we discuss the single and a gram, you will find that the current rating it changes according to tow the temperature and that the rating factor will change and you will see from the American tables. Okay, Just to it, for now. Just giving you the basic idea. So 127 going out to the table, you will find that 114 and 141 between them is the 127. So, of course we will choose the higher value, which is there 141 which means that we are selecting 35 millimetre square. Now, remember that Z in the power system or inside the distribution network. When we are distributing our power from the transformer, we should not exceed 5% as a voltage drop. Okay, 5% from the transformer to the lost. The point in Z add distribution network. Okay from the transformer does the customer. So for the TV system, we have a certain limit. Okay? And I'll show you now, but the first we have inside our array, we have an open circuit voltage or 407 7 vote on. I will tell you now Why do we need this way? So we selected their cable. According to the maximum current. Okay, Now we need to select is a cable according to the voters. So the water drop between the generator and the point off connection tools the public distribution network or indoor installation if it is an off great system shall not exceed 1.5% at nominal current. So we'll find that 1.5% from the generator A to Z at last, the point inside the indoor installation. Okay, 1.5% as a vulture drop. Now this value is inside the BV system. But for that distribution network from a generator or a transformer, the value shots will not exceed 5%. Now is the 1.5 is divided into two parts. Number one that D C line or that which is coming out off the B visa, is responsible for 1% off the vultures rope and assuming a 0.5% for the rest off the cabling. Okay, after the inverter and so on. So the D C. Line from that TV system. So the inverter we should not exceed 1% as of all strope. So I told you before that the open circuit voltage watts 407 7 Okay, so the maximum allow it vultures, rope or the decay inside. The voltage is 1% multiplied by C open circuit voltage. Which means that the maximum allowed or maximum allowable vultures rob is equal toe 4.77 So if the in book 407 7 then the outward maximum or the minimum value off the hour is 407 7 minus 4.77 Okay, this is he maximum allow. It avoids drop. Now there is a formula in orderto get the cross sectional area off the cable without exceeding Z 1%. So what is this formula we have that the cross sectional area equal Toe Zealand's off the cable okay, lets off the cable, including the boast of terminal and the negative thermal. You know that any D. C, for example, has a postive and has a negative line, one sending line and one receiving line or a returning line. So we have boasted and the negative this a mission off this lenses is equal toe villains. L so assumes that the going is 45 meter and see coming is fortify meter. Therefore, the torta lenses, 19 meters now is a nominal current is equal to 81.8. For this I is also inside the formula, representing the short circuit current. Okay, without any safety factor. And Z as this gamma is represent exact conductive to off cover at 70 Solicitors degree. Okay. Giving us for 6.82 Okay, This is a value which we are going to substitute here and the representing the maximum vaulters. Rob, allow it inside our sister. So find that as the voltage drop decreases or the allowing divorce drop decreases, the cross section area should increase. Okay, So as we increase the cross sectional area same as that distribution network as we increase the area as the bosses rob will decrease now by substituting now with this values, you will find that Z required the cross sectional area toe not exceed the maximum was drop is 32.298 which is 35 millimeters square. So number one we get the current according the tools e a short circuit current tomato blight by a safety factor. Then we should make sure that the walls drop should not exceed our value. Okay, So you will find that the Wardrop sometimes make the cable oversized. Okay, because excellence is very long. And then we will need toe oversize our equipment or our cable. Now we need to go tos ee or to get to see a single line diagram and understand how we selected each component. Now we opened our auto kit and you'll find here a BV system off great BV system which I designed the for you in order to understand. How well does the wiring o care? Because, ah, lot off students asked me, How does the wiring or care inside Z BV system or how to draw it? So I'm going to give you this photo cat file and already know the basic. Since I published ah group of videos about auto kit and has the basics off Okay, then you will ableto edit easily inside the A single line diagram. Okay, exhausted, dilating adding line. Removing the line editing takes very simple commands inside the oh took it. So first, let's see what is our system consisting off. So going like this or zooming in lie exists, you'll find that our system year consisting off 123455 modules and another five modules. Okay, each off this modules. OK? We don't have any strings. Now you can. It re blessed this. Modules A pie, a grope off modules Overture representing a strength. Another strange, another distinct and so on. OK, the bending on the system you have now we have this model, for example. All of them are similar to each other. We have here that each module here in our system having a 51. What? The short circuit? Current four. Each off this modules is 3.25 and bear the open circuit. Voltage is 20.7 vault. And if the system is 12 volt now let's see what happens here. You will find that each off this modules having a post of terminals, which is a solid line. This solid line as you see your Zestril, it lined. Representing is a positive and the negative is representing by a dotted line. Okay, one boast of and one negative. You'll find that all of this modules are connected. Embarrass The negative terminals are connected together and the post of terminals are connected together. So we said before that, inside the protection off our system, we said that the strings are protected by a fuse if their number exceeds three or more. As I remember, as anyone have towboat fuse. Okay for each strength. But now we have models, not strings. Modules which you produce are very short circuit current or a very small current. So of course, we are not going to add a fuse for each off. This modules now is the modules are connected. All of them are connected. Embarrassed? Okay, now this group off modules are collected. Throw a cable. Okay, One cable and this group off modules are connected. Toe the other cable and off course is this one. This five modules are barrel toes. This other five modules. Now this five modules with their cable goes through Fuze the protection device, and inside the junction box. This modules also go to Z the junction box by using a fuse and a cable. Now we will find that here Z cable use here Istan pwg, a WG assembly representing the American wire gauge, which is the American standard in cables. Okay. Is this one a w Geo s e dash toe? This one is located. The cable itself is located in sides of free air and is the ambient temperature. Orza atmosphere Temperature is 68 Celsius degree. Remember that this modules are exposed to sunlight and this one exposure to sunlight, including off course, is that cable here which takes all of the power from them and this cable which takes all of the power from them. This one is X supposedto the high temperature off this on, which is by measuring it at our location. We found it as a 68 syriza's degree. So for this temperature and for this group off modules, we decided that our suitable cable is this cable which is from the catalogue off the American Standard, and that fuels which is suitable is 30 and bear with 125 Walt D. C. So how we got this value? This is a question which is the most important thing here Now, at first, look at this. We said before that the fuse is selected. How, by getting Z short circuit current off the group off modules here which are passing through it and the multiplying it by 1.56 And the cable itself should withstand as this fuse current or higher. So let's see it now. At the beginning, you will find that them with your short circuit. Current one module is 3.25 Amber City, 0.2 to 5 members. Each module is City 50.25 Mbare and you have 123455 modules are collected through this cable. So we have five modules. Five matures so each one of them is 1.56 amount of blood by city 0.5 each module alone. This is a source of current off one module multiplying by safety factor. Give us 5.7 This is according to's that standard. Now we said that that Umbridge Taurus 68 solicitors degree okay for five models, we have five modules here. So five mother blood by 5.7 five multiplied by 5.7 Give us the current. Always a soft circuit current off these five modules is a 25.35 mbare. Now we need a few hours of which can withstand this value. So going toe Z fuels ratings which is found inside the market, we have to embarrass three and bear fire and bear five Embarrass 7.5 and so on. Now we have here is this is a 25.35 Mbare. So we should select a Z Higher fuels now is the higher fuels is the next after 25.35 is the 30 and they're not going to five. We selected See higher according to's e court. So we selected a 30 bear. Now we need a cable which you can withstand at least 30 And beer add Is this temperature? So we said that we selected that 10 a w g gauge So how we did we select it Now let's go to Z tables. Okay, here are some tables which representing the cables as you'll see here that cable for example 18 a wg 16 e w g 14 12 10 864 You'll find that as the number decreases Z on bare capacity increase. Okay, so c four have ah, higher capacity and bear capacities and 14. Okay. This is how the American standard works. Now we will find that here we have two tables, one for them For this one you will find that here that the conductors are parrot okay? Or in raceway cable or er thing or directly Barrett in Earth. Okay, is this table remember that here is This is very important that this values off Mbare as an example. The a w Z having a 40 or 50 or 55. According to's the rating off Khobar Conductor. Now, as an example, a wwc 40. And there this 1 40 am bear off. This cable is at a temperature off Surtees Eliza's degree. So this is the value at a 30 degree. If the temperature it changes by increasing or decreasing, then the capacity off this cable will change as also, Andi, I will tell you now how it will change. Now we will find here that we have this one also. He said it is Barrett inside the ground, and this one is in free air. Okay, exposed it away. Now we will find the air. Mazar a classification one here representing the temperature rating off the cover conduct. Okay. Remember that the cable is consisting off a conductor and insulation and the group off other layers inside it. Now the conductor itself, which is used to conduct electricity, which is here cover, you'll find it has a six is the 60 degrees Celsius, which is a maximum temperature for this cable for this cover conductor or 75 citizens degree or 90 syriza's degree and so on similar here. And you will find here the front insulation which they bend this on Z application itself, Okay, depends on the applications, the reasons off water and the atmosphere, and so on different factors and you can search for them by yourself. Okay, you can search and understand this alone now, for example, 67 degrees, 75 cities a degree and online services agree, and you'll find that the online services decree having busy higher capacities and 70 fives and sixes solicitors decree. Why? Because remember that the problem inside the or the deer creating problem, or the decrease inside the rating off the cable or any electrical machine as you towards that temperature rice. OK, when's the current eight floors inside the conductor it will be reduced by square, are or hate energy losses which will cause the temperature off this cable toe increase. So in orderto protect our cable, we have toe decrease its rating as an example, we both zero rating for our cable 80%. Okay. We just load our cable by 80% off its low rated value. Okay, now let's see if we have eight. It abuse team at a 40 bear. Okay. This is the value at success. Eliza's agree now what happened? If that Embry Charlie changes now going down here, I'm going to give you this five to you will find here that temperature correction factors. So what does this represent? If the ambient temperature waas other then 30 solicitors degree, then multiplies the ab capacities or the impair off the cable Boise appropriate factor or the correction factor here. So, as an example, if the ambient temperature this is in Fahrenheit and in in salacious degree now, as an example, if Z temperature war stencil is as degree or less and this cable waas conductor off 60 solicitors degree is then that on bear will be most blood by 1.29 What does this mean? It means that our cable can be overloaded over its capacity. Why? Because the temperature is lower, so the heat energy will be dissipated. Does the atmosphere as if you are calling your own? I gave one so you can overload your own cable. Now, as the temperature increases, you'll find different factors from joint 62 60 degree toe services. A degree 100%. Okay, you can load it, boy the 40 and bear all of it. As the temperature changes in the or finds a de factor, it changes. Now, let's look at our request. Okay? We have, uh we need here at 25.75 AM Bear or a 30 beer. But this is at a 68 solicitors degree. Okay? And we need search and be now, if we go to our cable table today will not cable where it's here. Okay, so we said that we have a 68 services agree. So we are going to choose either that 75 citizens degree or the nine syriza's agree. Okay, because that's surrounding itself. Having an ambient temperature off 68 is we should selected that conductor rating or the temperature rating higher than off course. Is that surrounding? So it is better to chose a nineties Eliza's degrees and 75 syriza degree. So by choosing 90 cities, is agree as an example, we are dealing with a 68. Eliza's every so going down here. Like here we said that we are doing with at 68 so that temperature here is from 66 to 7 Citizens Degrees System Richard This 16 states Eliza's Avery is between 61 66 70 solicitors degree. So if which was a cable off the nine cities degree capacity, then we will choose or 90.58 as a correction factor. So what does this mean? It means that if our cable is 40 and bear, then at 68 solicitors agree it will have 40 multiplied by this correction factor because it is a very hard and richer. So we need a cable mind stresses degree and, of course, free and air. Because we are dealing with solar BV. It's also where the cables are exposed in this case. So I want to buy by opening 58 Now let's about ozeki table now. We little's this table because we need a free air or in free air. Now we need or 0.58 So what are you going to do, Cal creator like this then and going? We have the current 30 and bear and or 300.58 So all 30 degree. Okay, Divided by all 0.58 Okay, so this will give us 51.7 and being so we need a cable from this part where it can withstand 51.7 toe and bear. And by adding that the rating factor it can withstand is a require the count. So 51.7 going like here 18 24 35 40 55 is the one which can withstand this value of current . So we'll choose at 10 a wc cable at nine. Citizens agree free in air. Okay. And we can choose any off this layer as an example used to or us Ito. So we'll find here that we selected our cable 10 a wg USC to in free air at 68 syriza's degrees. This one similar because there are five modules toe. And who said that the fuels is 30 and bear Okay, So you will find here that 10 a wg again again. If you don't understand, you will understand the now 55 citizens degree 55 bear at a 60. It's this is degree at a 60. It's listeners degree, so be multiplied by 0.58 So assembly, um, 0.5. It not blood boys a capacity or the Amber Capacity officer cable gives us 31.9. 31.29 is the current at which is a cable can withstand. At 60 it's Eliza's degree, and the fuel Zorzi on bare required 25. And it should be higher than the fuels, which is certain. So now our cable is accepted and they can withstand 30 or 25.35 and bear add the temperature off 60 its results degree. So we selected at first is that for rustic able and Z current Now going down like here. You will find that after disjunction books, we have one cable going toe that solar recharger control. Okay, so this cable should withstand what number one So does withstand dizzy, then modules together. Okay. Is that 10 modules that provide their short circuit current Saros this cable. So this cable should understand that 10 with yours and the fuels or their protection device or the circuit breaker here because why circuit breaker motor fuels, because a circuit breaker can considered as a disconnecting the switch for our BV system. It can turn on and off Z BV system. Okay, so we provide this circuit breaker toe, open it and where just to stop any flow off power from the TV system to our system. Okay, so we have here a circuit breaker now how we can select the balls off them. Similar as before. We have a 10 modules and each off system modules have a high 100.7 on bare as a short circuit current, so that all hotel short circuit current off them is 50.7 and bear. So the fuze rating or circuit breaker rating should build. Stand this 50.7 now going into our cattle here, you will find that we have higher then 50.7 c higher value. Because the court a request is this is that we selected the higher value 50 Amber. The higher than 50.7 is the sickest amber. So we selected the sickest e and bear. Now we need a cable that so does send 50.7 or greater sense of 60 and bear for the fuels. Now, there is a note here that again, depending on that temperature. Okay, depending on the temperature. Also surrounding you can select is a cable. So after the junction box where we collective that the vessel this is inside our home. Okay, so at the beginning, I forgot to mention that this system is a to kill. What? A small baby off grid system. Okay, off great residential system. Now the the now we off tens a circuit breaker. Who said that it should withstand 60 MB now at the junction box Or after these On some books, we have our cable inside our home. Okay, So the ambient temperature in this case is the fourty solicitors. The green. So now we need to select a cable in orderto wizards. Stand this on bear at Z 40 and 40 degree solicitors and 60 amber. So going into the cable again like this, we said we need four to citizens agree. So fourty solicitors degree. Okay. From 36 to 40. Solicitors agree, and we need it off course mind citizens agree or point. And I want you can You can choose any off them, but I chose the Ninth Raises agree. I'd like this one, so it has opening to 91 as a correction. In fact, now let's see the cable which cannot stand this. So we have current required 60 AM beer divided voice, a correction factor or going to line one give us Z required the value off Zika and 65.2934 So this is a value off the current required 65 point right? So let's go to the table where we have this one now going toe the they will we need at least how much we need at least 65 solicitors degree. But remember that we are talking about our home. So we're since we are talking about our homes, then we assume that our cable is buried inside the air's so since it is varied inside, there's and we provide online services degree with the standard temperature. Then go like this and searching for a value Greater Zen 65 point tonight. So 65 6 fighters this one so that this six a w she is the one which can withstand 75 bear at this solicitors degree. So six a wg having a 75 bear. Okay, so 75 multiplied by point mine one. Give us 68.25 Which is greater sense. Required the value off the circuit breaker, which is 60 and bear. So we can use a six a wg at months. This is agree. Parrot does the ground so we can go back toe here. So our fine and make it six dwt like this. Okay, then saving it again. So we selected our cable, and we have our circuit breaker going. Toes are so large. A charge controller going out off the solar charge Bottura off course, we will have the same cable. Okay, we assume that this one inside the Barrett or inside the Earth's or inside our building and this one is Barrett. And inside our building, you can choose post off them same cable, okay? Or you can, of course, choose us, Ito or at th datable H and or whatever is the most importing is that the current should was a stand. Okay. And 60 Mbare fuse. Okay. Is this one in circuit breaker and orderto prevent dizzy operation off our system and this one as a protection device. Now we will find that our system here, consisting off inverter. Okay, after that solar charger controller, we need at first charges E group off batteries. We have here a batteries each a six volt 200 bear each. You will find that this two batteries are barrel. Does this tool Barretto Sisto parallel to this to okay, This will produce assistant voltage off 12 volt. That's why you will find the year that the Walter Gear, which was written here, is 12 of all. This is a system voltage which you are dealing with. So this batteries, we'll provide power through a cable and this cable will go along with the BV system. Okies, Aviva system will provide power to the batteries and inverter, and the winds are by BV system is off. Then the patterns will supply the complete power. Tosa inverter! Now here you will find that we have here a circuit breaker. What? I fuels. Okay, whatever. Then you will find here D C loads. Okay, this is closer to having a five bear. And then we have at the same time in barren that inverter or a D C to a C conversion. Okay, then it will give us the final A salute Okay, so our system provides power to the batteries and the D C loads and then inverter, which supplies power to a salute. We have your an inverter off point. White kill. What with the 90% efficiency and the lowest voltage off this inverter is a low C D C. Voltage is 10.75 Now, this d c. Lord is five. Now, the question is is that how we can select the breakers and the cables? So for that D C load, the five member is the current off our load. So the fuels should be 1.25 months. Blood five. Remember here that the fuse here is for our lord, not for the baby system that we have a system waas five or the total Karen. Tomorrow is the short circuit current amount of blood by 1.56 But here we're talking about this route or a load away from the TV system. So five months blind by safety factor 1.25 give us 6.25 So which was air fuel off then? And bear, or a circuit breaker off 15 and bear and only chose a circuit breaker in orderto turn on and off this load, as would like to control it similar to our home. So we should have a cable, at least with stands at 15 and bear or hires M 15 and bear and the bear it in the ground. Since you are talking about with our building and we'll assume a temperature from 40 degrees solutions. Okay, since we are our in our building, So let's go and see it. Okay, we said four to citizens degrees so we can choose mind solicitors or 75 or 60 and this time I will change. I'll just choose as Texas is this degree. You can change or choose any time, but this one. Why in orderto reduces the cost? Because the higher the temperature more Costa to our cable or the BV system. So you said that we have 1/4 citizens degree, and we chose as secondary citizens agree now as a conductor. So the safety factor is 0.8 toe now going or the correction factor going back here or going to get to and said it is buried since its site is inside our building. So going down and down and down. And ah, again we said we said we need how much current women taking current divided by all 0.82 Give us 80 point. Tow it. So we need a cable which at least was the stands 18 Amber. So the best one here is that well, a WG case, A 20 on bear. Okay, with an insulation tw audio f as you would like. So this 1 12 8 ability is a suitable cable. So we selected a breaker all 15 and bear and as the all off Our components here should be higher than 12 volt. So is the closest Diffuse at least can withstand a 125 It if is there is a lower value then it's OK, but at least it should withstand that. Well, the vault of our system and the 12 aws Buf cable. So we selected the cable and breaker or the fuse for our d c. Ludes. Now we need those electives that men cable here. And this cable is similar to this one similar to this one. Why? I will tell you now this batteries contain all of the power and supplies. The poster was this cable. So the full load current buses through this cable and doesn't sometimes a full load current the bosses through this cable, Then it is divided into the inverter and Z D C loads This allowed to have a fight and bear . So it is considered as a neglected load, very small loot. So most off the current here will be the same current bossing Susan. But so is this. Cable will be similar to this one similar to this one. So we need to select Izzy cable here. According Toa the total current off our system and Z fuels So in the system here how we can select it. We have the salute and dissolute. Now we need toe toe selectors e main views. So we need the total current off D C plus a c. So there is a current. We know how we can get it. How Look at Z system Here is the current the a C currents absorbent here is equal to the power the import power off course and not the 0.5 point five is considered. There's the our boat power off the inverter, so we need the input divided by the lowest possible voltage. Okay, So somebody you'll find here that the A C current is equal to the import power, which is the 0.5 kill. What? Over the efficiency, which is 90%. This divided by just give us. Is the ambush power over the voltage. Okay, because we are dealing here with a single fish system. So over the voltage is which is 10.7 point, which is that minimum voltage. Then after this, we will multiply by 1.25 which is the safety factor inside our system. Okay, because our circuit breaker or our fuses is de rated you dozy surrounding conditions. So by Martha blamed by 1.12 If we get a current off 64.6 Amber's this is a D. C. Is This is the A C car for the d. C current. They will find that 1.25 months of blood by five, which would give us six appoint 25 1.25 cents our load here D c so multi blotted by five. Give us 6.25 amber. So this current as the submission off Boca give us is the total current off the system. So that's what our current 71 pair so going back here through that fuse 6 to 1 and bear the closest one is a 70 bear. Okay, let's see it against of into one 71 tackles. One is the 80 members a higher value. So it and bear is a fuse goingto over diagram 80 and bear. Here is our views. Now we need to selectively cable. So we need a cable which you can withstand at least 80 and bear at a 40 solicitors degree and the parrot inside the ground since it is inside our building. So going toe the tables, the air balls here. So we said going down here like this. So we need at least something which you can withstand z 80 and bear at line two solicitors degree at 45 syriza's degree. Okay, so we selected a cable Minds reasons agree here. Okay, you can select a 90 or 75 or 60 cents is the ambient is 40 solicitors degree. But as a change, I'm going toe chose the nineties Eliza's degree, so mind to citizens degree and we said that our temperature is 40 slesers degree. So the correction factor is 0.291 So all going to 91 Like here we have the required to current 80 over a 1.91 So the cable required should at least 78 points online. And they're going back 78 point line. And there we said it is buried and sit at online. Syriza's degree is that embrace your rating? Nine. Clesius going down and at least should withstand 78. So this one is rejected. This one is rejected. This one is acceptable. 95 there. So therefore, e w Z parrot in ground can understands that required the current. So you'll find that we selected or a WG you use r u S e to Barrett cable. Okay, so we selected now our cable According toe the rating. Now, the lawsuit thing is that all components and should have at least a d. C. Walter reading off 1.25 motor blood by 20.7. Okay. Why? Because that 20.7 is the voltage open circuit. Okay, let's to get back like this. The all of this models are embedded so that maximum voltage is 20.7. So Z gail components or at least 1.15 which is, if the fact or amount of blood by Z open circuit voltage off our system which is 26 a vote . Of course, all of our component are away from this values. They are very high inside their high voltage rating. The most important thing is the current rating and the voltage drop. Okay, we did not add in your wardrobe here, since we don't know silence off the cables. This is just an example. If we normal sentence off the cable, then we would need toe identifies that distance. And if the votes drop exceeds, the 1% is then we'll need toe oversize our cable. So in this video, Wade's cause disease Single line diagram over off BV system Onda How does electricity cables and fuses 67. Simulation of PV Cell In MATLAB And Obtaining V I Characteristics: Hi, everyone. In this video, we would like toa simulate the Beav easel and obtained the V i characteristics of four system using Z Matlack. So we're going to get their voltage current and power characteristics according to the variation inside their radiation. So the first thing you are going toe create a new Samuel Inc so new Zen Similar Inc model. Now we need to add some components. So the first thing we would like to add is that solar cell itself. So we're going toe that same you link or the library, browser or simmering library. Then we are going toe types all ourselves in the search ter solar cell. So now we have the solar cell, which is inside there, seem escape library Really inside the simmering. Okay, so this is a library inside the meth lab itself, So double correct and added toe that model untitled. Okay. Is this model you'll see here having is that Solar said like this. Okay, so we have here our solar cell and that two terminals off the sort of seven people step as you see here, there is a positive and the negative. And here the radiation is going toe their solar cell. So we need toe adds the constant which representing the radiation going through is a cell. So how we can do this simply by going toe the simulator library, then piping Afghanistan, then going that went toe that seem escape. Okay, where were this constant? Ok, since this one is from the US library off that same escape, this one. Therefore, we will have to get a constant, which is with from the same library. Okay, this is from some escape library. Therefore, this constant will be from that same scape library. Some scape library, assembly deals with physical components. Okay, Physical components we would like to simulate inside the meth lab. So right, click And after the model Untitled. So now we have our constant this constant representing the radiation from the sun. OK, radiation from the sun going is through ourselves. So we'll take Here's the hour, but like this and connect it toe the solar cell as if it is the Roddy. So what is the value of variation? We are going to draw the voltage current characteristics with a different radiations. So we'll assume that the radiation here is 1000. What about meter square. Okay, apply then. Okay, So this is the 1000. Is the amount off radiation falling on the solar cells now? The second step is that we would like to add an a meter in orderto measures the current here and would like to add of all two meter in order to measure the voltage across zeroed. But we would need to add a variable resistance. Okay, which is representing our load. So if we look at the library, 40 seems cape, you will find that we had a variable resistance. Okay, we're is the viral resistance. Okay, let's time it resistance. Enter then search for the same escape. And here we have our valuable resistance. Why? We're using a variable resistance because we would like to get a variable loop. We would like toa Jonuz. Load itself is a resistance off the road and see how it will affect the voltage and current off the solar cell. Okay, because the variation off the Lord will it change the VR characteristics? So let's see what will happen if we adds a lot of resistance at a Ziploc model arm tighten . This one is called the Entitled Model in Matlin, then control are toe rotate this symbol or this component. Then we're going to take the post of connected toe this variable resistor and the negative to it. But before this, we need toe adds a meter in order to measure the current. Remember that this one is B s same escape this one Esteem escape This one seem escape. All of them are can be connected together because there are from the same section Z sim escape part. Okay, now I would like to add and I meet him so that a meter inside the same you link here is can be considered the fourth the same escape school. Dizzy current sense. Okay, current sends off, then enter. Okay. Current should be here E current. Okay. This one is also from Sim Escape Library. So we're going to the one current sense. Right? Click and add toe model. Untitled at block does the model untitled. Now we have our current source. So not current sources. The current sensor or the A meter. Now we would like to connect Izzy. The current goes out from the cell so rosy current sensor then throws the variable resistor . So we will take this terminal and the connected here and the second eternal here and connected here. Remember that the value of the A meter can be taken out from here from our here. Okay, Now we need also a voltage censored because it would like toa measure the voltage across zeroed. So going here and typing vaulted your sense Voltage sense Ok, enter. So we have our voltage since or right click the air to Z had blocked Oh, the model arm fighting Now we have our voltage like this. Now our voltage have a two term it's one which is this one like this which is measuring this part And this the other tenants to measure this second part. Okay, And this is the hour off the vault a meter This is the abbot off the meter now our solar cell will be connected towards the other tenor like this. So we have solar seuin providing power through a current sensor Does the variable resistor which is considered as our load and then toe the voltage sensor measures the voltage across zero Now the next step is that we would like to add the grounding for this part so going to the library and driving ground, then going down to Z seem escape again. You'll find here electrical reference. Right click is an ad block toe. The model are entitled. So we have here our electrical er thing then connected this terminal toe this part like this. So we, er sit or provided and er thinking node toe ourselves because this one is the highest voltage wizards, Victor, toe the ground or zero voltage. Now, the next step is that we would like to add a bloke called Z sold over configuration because we are dealing here with the same escape. So we will need to add a solver conflagration toe this morning. So let's add Z silver, then going toe escape. My exists sold for configuration added toe the model are entitled. Then we'll take this one. Okay, is in connected here. So this part on double click on it then use local silver is in a ploy. And okay, now the second step is that we would like to add the power sensor. Okay, We would like we have the current we have the voltage and we need also to add the power. So we need a broader. Okay, Because the power Z power produced from a solar cell is equal to the voltage voltage here across zeroed martyr, blood by sea, Current going through zeroed. So we'll go here toe the product product in orderto multiplies E voltage. And current is an ad toes e block. Now, you're not something here that we have the product here like this and we have a problem here now if we connected the current here, you'll see that it is not be ableto connected to it. Why or even the water. If we take the voltage like this and added does this book, it can not be added. Why? Because this to our from seven escape library. But this one is from Samuel Inc library. So we did this and they exist. So we need something. Toe changes the signal off z three, the current source or the current sensor from being a seem escape to a simulated. So how we can do this So we'll go to the singling library again. Then type convert. Okay. And converters reason here. Okay, then goto the same escape you will find here is the same escape that we have a similar link toe seem escape converter or seem escaped to simulate converters. So we have two types of converting. One can change a from Z signal off. That's him. Escape toe s a mewling. And this one it changes from that same you link signal in tow as him escape or are physical signal. So what we have here? We have a physical signal, which is that from the solar cell Physical signal from the current and physical single from the sense or the vault sensor. So we need to convert this physical signal toe a simmering signal. So physical, which is thesis escape in tow s a mewling. So at two z model untitled, we have this one here, then connected this one z current toe This part then from the Samuel Ankle toes the product . So we converted the same escape or the physical signal into a simulating four simulation signal. Now we need to do the same force the vaulted your source So we will just right click. OK? And copy isn't right. Click and based Now we have the voltage converted toe a simulating signal. So now we have the output off. This one is the power and our it off This one. This work is the current as a singling signal this one as a voltage singling signal. Now we need to add a working space in order to store the values. OK, so workspace for the voltage work is waste for the current work is based for the product or the power. So going like this to the simulate again and diving workspace enter goingto the Samuel Link you will find here at two workspace. So ad block does the model. This bloke and we need one. Foresee current one for the voltage and one for the product or the power. So we will just select it is in control and the drag toe doublet. Kate, it double click. They named it as he current, then, Okay. DoubleClick Voltage. Okay, power. Okay, so we have power. Which is the Albert from here. So here current from here to here, which is the Albert off the convert is the voltage from year to here. The vault ege. Okay, let's religious the Albert here. This is after converting from a physical signal or from some escape toe Aceh mewling signal . So we have the current voltage and dizzy power. Now what is the thing remaining? That last thing remaining is two things. Number one, we need toe store, these values. So whatever the change in the current wins, a load changes. I would like to save the valleys off the current voltage and power for the corresponding value off resistant. So how we can does this same bullyboy double frequency current, we will click on say, format as an array. Okay, save this one also, as an array, we would like to store all this. There are a lot of the values. When's that is the story changes and array. Okay, now what we need to add, we need toe changes. The variable resistance. We need to change it. So how we can change it by adding a ramp in boat ramp ramp like this soul finds it is as a mewling so air toe the model untitled. So we have our ramp now. Zero. And here I would like to change. Is he from 0 to 1? Okay. Start time. Zero. And the slope equal one. Okay. Now is the When we connected toe the resistance in order to change its value will see that it cannot be added. Why? Because the Ram here is a simulating. But this one is a physical load or seem scape lewd. So when did this one? So we need to add Z converter. So converter, in order to change it from same escape to physical or from the similar link, it'll physical. So from Samuel Inc. It'll physical air to model entitled. So this one is a simulating going here, Samuel in converted to a physical value. Then through Sarah, system will find disconnected now toe the resistor. So what does that mean? It means that it changes from zero to the maximum value we are changing. Get okay. We are increasing our lord gradually and storing is his values. So we have first zem the radiation at 1000. Is the solar city feel publicly conceptual or so you will find? Here's a different characteristics Z temperature and everything would like toa ad about this This cell OK, your fund short circuit open circuit Z radiance and so and so on. Every single like to add you can add it here in order to on simulate your own solar said. And your funding is the equivalent equation for this block diagram, then click and going. Okay. Now we can simulate this one by just clicking or run. So we simulated at 1000. Now, if we would like toa change it at my own 100 Zen would love click here and make it mine. Hundreds in. Okay, then after resists. Okay, we have current voltage power. Okay, This are the barometers at 1000. What? Burr Meter square or at a radiance? 1000. Now, if I change it 900 then I need to change. This parameter is the storage of variable Gunter number one. Voltage number one, our number one. Okay, so this are the sea variables. Which will the store, It's equivalent values at 900. What? Very meter square run again. Change it. Toe 100. Okay, current number two Voltage a number two. I'm power number two. Then run. Now we have it on. Let's make it 700. Okay. Number three. Voltage in number. Syria. Okay, our number three. Ok, as in run 600. We are going to do this until 500. Okay? And you'll see the results. And when we blow them inside the meth lab, okay. Each erogenous or each variation inside the See what? Burr Meter square. We are giving it at the front of variable for the voltage and different value for variable for the power run. Lost. 1 500 Okay. Going here. Toronto number five. Okay, vaulted the number five. Okay. Power number five. Okay, run. So now we often for 1000 for mine? 108 107 100. 605 100. So we have six different values for voltage current and power at a different origins. Now we need toe draws, the voltage current the characteristics and Izzy vaulted with the power. So how we can does assembly, we goto the Matlack itself back again and you'll find here inside the workspace current, current. 12345 Bauer, Bauer 12345 And voltage. 12345 This is the values which we would like to store inside our Matt Let okay, We stored by simulating at the front Iranians Now I would like to blow them so we will pipe in the command. The window blood, the bracket. We need toe bloat. Ze uh, current. Okay. Or Z? Let's make it the voltage voltage current then the voltage A number one voltage One current one voltage do God! Aunt dual Ah, voltage Cering Current three voltage four Current four Voltage five Current five Okay, so we have the five different values. Then we will close the pact, then enter and you'll find what will happen here. You'll find years at five The front of values we say vaulted You can't means that the X is voltage and dizzy. Why is current voltages X y x Y x y So fund here. 123456 This is six the front values for the voltage across the current. Okay, this is that voltage and the current and it's a variation with respected toe time. Okay, Now the question is how I can name this figure name here and another name Here is the X and y and the window itself. So we can go toe the math lab again and type x label explainable. Crack it then one colon on. Then we would like the extra busy voltage Give Aldige Okay then close It cracked. Enter Why? Lia ble Then bracket Colon. Then make it easy. Current and finally title bracket. I would like to name it as V I, um characteristics, Characteristics. Okay, on the i characteristics of four BV in self, then close the bracket. But at the beginning, we have to end this one and this one. Okay, then enter. Now let's look at see figure. Now you will find your VR characteristics for B visa, which is he title here. And there's the X axis is named as the vaulted. The Y axis is named as a current very simple and very professional in looking. Okay, so now we need toe block Z voltage and current. So I plot is a voltage with power. Voltage one Power one a voltage to power do voltage three Power three Voltage four power For now, we are just a We would like to blot Z voltage and Zika as the vaulted with respect A to Z power at a different loads. Okay. To see the variation off the load or the vaulted with the maximum power Voltage e five, Power five. Okay, we have five. Then enter. Okay, that's easy. Blotting. You'll find yours applauding will find here here the variation off the voltage and the equivalent of power. You will find that at a different radiance. As the radiation increases, you will find that the equivalent of power increase okay at the same voltage as the same voltage ear. The maximum power increases as the irradiation in priests. So you can also add here the fighter excel able again. Let's limit as voltage and why label as power and title name it as, ah her being being characteristics, Characteristics four BV cell like this enter and see again You will find your VB characteristics for a B vessel is the power and voltage. So in this video, will you learn it? How I can take a solar cell and they get their V I characteristics and the VB characteristic using Z Mettler program. So I hope you'll benefit from this video and see you in another lecture.