What is thin film solar panel?
Thin-film solar cells require less material and typically use a silicon layer that is only one micron thick, which is about 1/300th of the width of monocrystalline and polycrystalline solar cells. the quality of the silicon is also lower than that used in monocrystalline silicon wafers.
Many thin-film solar cells are made from non-crystalline amorphous silicon. Because amorphous silicon does not have the semiconducting properties of crystalline silicon, it must combine with hydrogen to conduct electricity. Amorphous silicon solar cells are the most common type of thin-film cell, and they are often found in electronics such as calculators and watches.
Other commercially viable thin-film semiconductor materials include cadmium telluride (CdTe), copper indium gallium diselenide (CIGS), and gallium arsenide (GaAs). A layer of semiconductor material is deposited on an inexpensive substrate, such as glass, metal or plastic, making it cheaper and more adaptable than other solar cells. Semiconductor materials have a high absorption rate, which is one reason they use less material than other cells.
Thin-film cells are much simpler and faster to produce than first-generation solar cells, and there are a variety of technologies that can be used to make thin-film cells, depending on the manufacturer's capabilities. Thin-film solar cells like CIGS can be deposited on plastic, which greatly reduces its weight and increases its flexibility. Cadmium telluride is the only thin-film that has a lower cost, a longer payback time, a lower carbon footprint, and uses less water over its lifecycle than all other solar technologies.
However, there are many drawbacks to thin-film solar cells in the current situation. The cadmium in CdTe cells is highly toxic if inhaled or ingested and can leach into the ground or water supply if not properly treated during disposal. This can be avoided if the panels are recycled, but currently this technology is not as widely used as it needs to be. The use of rare metals like those in CIGS, CdTe and GaAs can also be an expensive and potentially limiting factor in the production of large numbers of thin film solar cells.
The overall conversion efficiency of thin film is not as high as crystalline silicon, which is an important reason for the lack of widespread adoption, and the fact that some thin-film solar cell wafers can be more expensive than crystalline silicon and require higher temperatures for production and storage.