A solar cell is a thin slice (‘wafer’) that is usually cut from a large silicon block. Silicon is a semiconductor. Thin metal wires are applied to the silicon wafer to conduct the electrical voltage. This allows the solar cell to convert sunlight into an electric current.
Different Types of Silicon in Various Solar Panels
There are three types of silicon commonly used in solar panels, each with differences in efficiency and lifespan. Generally, crystalline silicon is of the highest quality.
Monocrystalline silicon is widely used in solar panels and is known for its high efficiency and quality. In monocrystalline solar panels, the individual crystals are further processed and aligned in the same direction, allowing them to generate more energy per surface area due to their purity. This is the most expensive production method but results in the highest efficiency. Monocrystalline solar cells can be recognized by their rounded corners, as seen in the image next to this text.
Polycrystalline silicon is also commonly used in solar panels. Due to differences in production methods, polycrystalline silicon has a slightly lower efficiency than monocrystalline silicon. In polycrystalline panels, the individual crystals are not processed further after solidification, making production shorter and the panels cheaper. Polycrystalline solar cells can be recognized by their squared-off corners, as shown in the adjacent image.
Amorphous silicon differs from crystalline silicon because it is made from silicon powder rather than crystals. The advantage of amorphous silicon is that it is inexpensive and flexible. However, it is generally not the best choice for solar panels, as amorphous silicon cells have significantly lower efficiency. The adjacent image shows an amorphous solar cell, recognizable by its uniform black appearance.
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Monocrystalline silicon
Monocrystalline silicon is widely used in solar panels and is known for its high efficiency and quality. In monocrystalline solar panels, the individual crystals are further processed and aligned in the same direction, allowing them to generate more energy per surface area due to their purity. This is the most expensive production method but results in the highest efficiency. Monocrystalline solar cells can be recognized by their rounded corners, as seen in the image next to this text.
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Polycrystalline silicon
Polycrystalline silicon is also commonly used in solar panels. Due to differences in production methods, polycrystalline silicon has a slightly lower efficiency than monocrystalline silicon. In polycrystalline panels, the individual crystals are not processed further after solidification, making production shorter and the panels cheaper. Polycrystalline solar cells can be recognized by their squared-off corners, as shown in the adjacent image.
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Amorphous silicon
Amorphous silicon differs from crystalline silicon because it is made from silicon powder rather than crystals. The advantage of amorphous silicon is that it is inexpensive and flexible. However, it is generally not the best choice for solar panels, as amorphous silicon cells have significantly lower efficiency. The adjacent image shows an amorphous solar cell, recognizable by its uniform black appearance.
Price Reduction Due to Advancements in Silicon Production
Solar cells require a pure form of silicon. Fortunately, silicon is abundantly available, such as in sand, but refining it requires a lot of energy and money. In recent years, technological advancements have made it possible to achieve the same efficiency using increasingly impure silicon. This has led to a price reduction that ultimately lowers the cost of solar panels.
