How Is A Solar Panel Made?



A solar panel is a collection of photovoltaic cells that has the ability to absorb the sun's energy and convert it into electricity. The ability to convert the sun's energy was first discovered by Antione-Cesar Becquerel when he exposed a battery in sunlight. It was able to take 1% of the sunlight, but more and more scientists believed that we can harness more. This belief that soon turned out to be a fact gave birth to solar panels. 


Solar panels are manufactured by solar companies and it goes through a rigorous process of heating, molding, and cutting. Here is a step-by-step explanation of how silicon ends up to be a solar panel. 


Phase 1: Converting silicon


Before explaining how silicon is converted, you should know that there are 3 types of solar panels - monocrystalline, polycrystalline, and thin films. They vary in the kind of silicon they use even if they follow a similar process. 


Solar panels are mostly made out of silicon which is the main component of sand. Silicon is collected in the form of solid rocks until they are melted in a furnace using very high temperatures. The heat forms them into ingots forming cylindrical shapes. During this process, boron is added so that it creates a positive polarity. This is because silicon in its purest form cannot be made into solar cells yet. Once boron is mixed in, they form a semiconductor fit to carry electricity. 


Phase 2: Cutting into wafers


The next step is cutting the silicon cylinders into thin sheets to be put on the panel. This is done using a circular saw that cuts them into very fine sheets similar to paper. Once they are cut, the wafers would look like rectangular or hexagonal pieces. It's supposed to be in this shape because it fits well in the size and shape of the panel where they will be put. 


Right after cutting, the wafers are sometimes polished. Just recently, it was discovered that rough surfaces can absorb light more so some manufacturing processes no longer polish wafers. Aside from that, all wafers are coated with anti-reflective properties so that they don't reflect light. 


Phase 3: Putting together to form a panel


The wafers are treated to become solar cells that can absorb and convert solar energy. The coating that was put in the previous phase helps in absorbing light more rather than just reflecting it. 


Right after, phosphorous is diffused to be put on top of the solar cells. This will give a positive charge to the already negatively charged silicon. Then, they are put together to form a panel with metal conductors in their surroundings.