Solar Cell Primer
What are solar cells made of? The answer to that question depends upon the type of solar cell you are thinking of. The traditional solar cell is the most common solar cell in use. It is of what has been termed the first generation of solar cells. Exciting new technologies have come into use creating second and third generation solar cells that use new methods and materials in their manufacture.
First generation solar cells are made of monocrystaline silicon wafers which have a purity level of 99.99% . Silicone makes up almost twenty six percent of the earth’s crust and is the second most abundant element, with only oxygen being more common. Silicone crystals can be grown from one to eleven inches (300 millimeters) in diameter in laboratories under controlled conditions. These crystals are then sliced very thinly into wafers which are then cleaned with a weak acid solution, doped to change their electrical properties and chemically etched to remove layers from their surface. Individual solar cells are formed from a single wafer of silicone crystal which are then connected together to make a solar panel.
Second generation, or thin-film solar cells, are made of a variety of materials. Cadmium telluride is layered with cadmium sulfide to form one type of solar cell. Copper indium gallium selenide is also used as a light absorbing material for another type of solar cell. This type of solar cell is less efficient than first generation solar cells, but they are cheaper to make. Amorphous silicon, which is the noncrystaline form of silicon, can be used to make solar cells as well as micromorphous silicon modules. These materials are applied to glass or ceramics using either electroplating, vapor deposition, or ultrasonic nozzle methods.
Advanced thin-film photovoltaic cells are also called third generation solar cells. These solar cells make use of printing technologies to print photovoltaic substances on flexible materials. This is a relatively new technology which is still developing. But solar cells made with printing methods have achieved pretty high efficiency levels and at a lower cost than previous production methods. Expanded uses for these materials include solar cells integrated into clothing to power hand held devices. Solar cells may also be integrated into auto paint which could turn the car’s body into a solar collector.
Evolving technology has resulted in new materials to be developed for solar cells to be made from. Solar cell material has evolved from growing silicone wafers and slicing them very thin to printing solar sensitive materials on flexible sheets. And the future promises more promising uses as solar cell technology continues to improve.
I keep hearing that although the placement of solar panels is expensive, the local electric company will begin sending you checks in the mail rather than bills because you begin contributing power to their system. Is this true?
Also, I hear that people can make their own solar panels in their backyard yet I have not yet been able to find an easy way to do this. I am definitely interested. Tired of paying 250-500 per month to the electric company!!!