Solar cell power generation efficiency

The highest photoelectric conversion efficiency of monocrystalline silicon solar energy reaches 24%, which is the highest photoelectric conversion efficiency of all types of solar cells. But the production cost of monocrystalline silicon solar cells is so high that it cannot be widely and widely used in large quantities. In terms of production cost, polycrystalline silicon solar cells are cheaper than monocrystalline silicon solar cells, but the photoelectric conversion efficiency of polycrystalline silicon solar cells is much lower. In addition, the service life of polycrystalline silicon solar cells is also shorter than that of monocrystalline silicon solar cells. . Therefore, in terms of cost performance, monocrystalline silicon solar cells are slightly better.
Researchers have found that some compound semiconductor materials are suitable for solar photoelectric conversion thin films. For example, CdS, CdTe; Ⅲ-V compound semiconductors: GaAs, AIPInP, etc.; thin-film solar cells made of these semiconductors show good photoelectric conversion efficiency. Semiconductor materials with multiple gradient energy band gaps (the energy level difference between the conduction band and the valence band) can expand the solar absorption spectrum range, thereby improving the photoelectric conversion efficiency. A large number of practical applications of thin-film solar cells present broad prospects. Among these multiple semiconductor materials, Cu(In,Ga)Se2 is a solar light absorbing material with excellent performance. Based on it, it is possible to design a thin-film solar cell whose photoelectric conversion efficiency is significantly higher than that of silicon thin-film solar cells, and the photoelectric conversion rate that can be achieved is 18%.