The solar panel is the key component of any solar photovoltaic system, which takes the sun’s energy and converts it into an electrical current. There are three main types of solar panel (as well as the hybrid version) currently in commercial production, all of which are based on silicon semiconductors:
This type of solar cell is made from thin wafers of silicon cut from artificially-grown crystals. These cells are created from single crystals grown in isolation, making them the most expensive of the three varieties (approximately 35% more expensive than equivalent polycrystalline cells), but they have the highest efficiency rating – between 15-24%.
This type of solar cell is also made from thin wafers of silicon cut from artificially grown crystals, but instead of single crystals, these cells are made from multiple interlocking silicon crystals grown together. This makes them cheaper to produce, but their efficiency is lower than the monocrystalline solar cells, currently at 13-18%
These are the cheapest type of solar cell to produce, are relatively new to the market and are produced very differently to the two other types. Instead of using crystals, silicon is deposited very thinly on a backing substrate.
There are two real benefits of the amorphous solar cell; firstly the layer of silicon is so thin it allows the solar cells to be flexible, and secondly they are more efficient in low light levels (like during winter).
This, however, comes at a price; they have the lowest efficiency rating of all three types – approximately 7% – 9%, requiring approximately double the panel area to produce the same output. In addition, as this is a relatively new science, there is no agreed industry-wide production technique, so they are not as robust as the other two types.
Over the years technological advances have been made in the production of solar panels, with an increase output to 300-350 Watts.