Hello friends! Welcome to the third video of on-grid solar panel tutorial series I Shubham Mandot, will discuss about the types of solar cells, their construction, and how to read a data sheet Before beginning with it, let us have a glance at the previous activity In which, we asked you t calculate the monthly bill of your house for these conditions The answer to it is Total units consumed = 8.85 kWh per day And the total cost per month = Rs 1327.5 I hope that you would have found the correct answer If not, then comment below and we will point out your mistake Let us begin with this video Let us see what are the types of solar cells Friends, there are 3 generations of solar cells First generation : Mono crystalline and Poly crystalline second generation also called the thin film solar cells : Amorphous and silicon Cells under 2nd gen are Cadmium and Telluride The cells of second generation have a very low power generation.
These are used in calculators The solar cells we see in calculators are of this type Third generation : Organic and Quantum dots One more type of solar cell is there called the concentrated photovoltaic cell This type of cell does the function of concentrating the sunlight at a point and then generates the electricity This increases the efficiency of electricity generation Let us now discuss about mono and poly crystalline cells We are discussing these because of their excessive use Mono crystalline cells are uniformly colored. At times they are completely black .
Poly crystalline have patches of colors.Like if it is blue in color, then there will be patches of different shades of blue Let us see what are these and what is their difference Mono Crystalline and poly crystalline Mono is manufactured from a single crystalline silicon Friends. we build a complete mono crystalline cell from a single silicon crystal Whereas Poly crystalline cell is manufactured from multiple crystals of silicon They are melted and then a cell is made Mono has an efficiency of about 15 to 20 % whereas that of poly is 13 to 16% Though the efficiency of the latter is lower, it has a few advantages too which will be discussed later Mono crystalline , as it has higher efficiency, requires lesser space In the same manner, poly crystalline requires larger amount of space Both of them have 25 yrs of warranty Now we will see what can be the advantages of the poly crystalline Larger the efficiency, greater will be the price It is not possible to get everything at a cheaper rate Mono crystalline are the costliest cells in the market Poly crystalline is cheaper in price because of its cheaper manufacturing process So, these fall in an affordable range The waste generated during the manufacturing of the former, is very much As we discussed that it is made from single crystalline cell So, to carve a single silicon cell to make a mono crystalline cell, will generate a lot of waste and this waste cannot be used to make any other cell.
It becomes useless Whereas, minimum waste is generated in poly crystalline cells The performance of mono crystalline cells is highly affected by temperature The same is true for poly crystalline but, it is comparatively low Let us discuss how a solar panel is constructed A typical solar cell looks like the given image The white lines, that are visible, are call the bus bars which conducts the electricity generated. Here, only two bus bars are shown. Usually there are four to five bus bars in a cell How are cells connected? Solar cells are connected in series This arrangement leads to the formation of a solar panel In our solar panel, the cells are connected in series. And if solar panels are connected in series, then it is called a solar string And when solar strings are connected together, they form an array.
Let us discuss its components The first component is a frame Frame is a structure that supports and protects the complete solar panel system Glass protects the panel from dust, pressure or external shocks or forces to prevent it from getting damaged Encapsulants are attached above and below the solar panel to fix its position These work just like a capsule. As it performs the function of protecting the inner material, similar does the encapsulants then there is a backsheet and a junction lbox. About which, we would discuss later. Let us keep only until this in this video Let us now discuss the different wattage ranges of solar panel As you can see, 20 to 350 Watts and more of solar panels are currently available in thee market How to determine the quality of the panel or which type of solar panel is suitable for your roof top There are 4 ways to determine that See the number of bus bars in it.
The more the number of bus bars, higher will be its efficiency. But if they are more, it causes a shading effect and may decrease the intensity of sun rays and may decrease the effective area So, we should select optimum number of bus bars i.e, 4 to 5 Then comes the module efficiency means the efficiency of your solar panel Then comes the temperature coefficient i.e, the current, voltage and power depends very much on the temperature of the panel The variation of these parameters with change in temperature is also important to know Finally comes the warranty.
On that basis only, you select it Now, you might be thinking that it is better not to buy one than to inquire about all these things No need to worry friends, all these things are mentioned in the datasheet of the panel itself So if we learn to read the datasheet of the panel, then we can know its quality or whether it is suitable for our purpose or not Let us see how to read a datasheet In our previous video, we saw how electrical characteristics are shown in a datasheet We discussed about maximum power, open circuit voltage, short circuit current, voltage and current at maximum power One of our four requirements that is module efficiency is mentioned here itself It lets you know how much efficient it is Further, let us see thermal characteristics In your datasheet, there will be a table of thermal characteristics In which, you will get temperature coefficient of current and voltage as well as of power As you can see, the values are written in front of the titles like 0.681 for current temperature coefficient, for voltage, there is a negative value for voltage it is -0.2941 and for power it is -0.3845 Now, what does this positive and negative sign indicate? If there is a positive sign or if there is no sign, then that quantity will increase with temperature That is, if temperature increase, current increases as well In the same way, for negative sign, the values of the entity decreases with increase in temperature.
Like voltage and power will decrease with temperature the thing that should be kept in mind is that these changes take place only when the temperature is above 25 degree C 25 degree is the STC i.e standard test condition of the cell When the temperature of the cell is more than 25 degree , only then these coefficients become effective Let us now see warranty that too is mentioned in the datasheet Here , it is written that 10 yrs limited product warranty And 25 yrs of Power output warranty Power output warranty is of two types : minimum 90% at the end of 10 yrs means that at least 90% of the rated power will be obtained til 10 yrs That is if the rating is 250 Watt, then you will get at least 90% of it for 10 yrs And till the end of 25 yrs, you will atleast get 80% of power Which means if you use the panel across its life span, you will obtain minimum 80% of its rating continuously Let us now see the exact appearance of the sheet We have considered the data sheet of a 250 W solar panel of WAAREE company for an example We saw the electrical characteristics, There are mechanical characteristics also mentioned where weight, number of solar cells per module, its type( mono or multi crystalline) front cover material, encapsulant material, the material of the junction box is mentioned Few more things can also be seen here.
Design specifications can also be seen as well as the I-V curve variation with temperature I-V curve is crucial for understanding the system as well as solar installation And it will be explained in the next video I hope you would have liked his video. If you liked it, then do like , share and comment your questions below. Thank you..