Solar cells generate electricity based on the photoelectric properties of specific materials. Black bodies (such as the sun) emit electromagnetic waves of different wavelengths (corresponding to different frequencies), such as infrared, ultraviolet, visible light, and so on. When these rays are irradiated on different conductors or semiconductors, photons interact with free electrons in conductors or semiconductors to produce an electric current. The shorter the wavelength and the higher the frequency, the higher the energy. However, the energy of rays of all wavelengths can not be converted into electric energy. It is worth noting that the photoelectric effect is independent of the intensity of rays, and only when the frequency reaches or exceeds the threshold that can produce the photoelectric effect can the current be generated. The maximum wavelength of light that enables the semiconductor to produce the photoelectric effect is related to the band width of the semiconductor. For example, the band width of crystalline silicon is about 1.155eV at room temperature. Therefore, light with a wavelength less than 1100nm must be able to generate the photoelectric effect of crystalline silicon. Solar battery power generation is a renewable and environmentally friendly way of generating electricity, which will not produce greenhouse gases such as carbon dioxide and will not cause pollution to the environment. According to the production materials, it is divided into silicon semiconductor battery, CdTe thin film battery, CIGS thin film battery, dye-sensitized thin film battery, organic material battery, etc. The silicon cells are divided into monocrystalline cells, polycrystalline cells and amorphous silicon thin film cells. The most important parameter for solar cells is conversion efficiency. In the silicon-based solar cells developed in the laboratory, the efficiency of monocrystalline silicon cells is 25.0%, the efficiency of polycrystalline silicon cells is 20.4%, the efficiency of CIGS thin film cells is 19.6%, the efficiency of CdTe thin film cells is 16.7%, and the efficiency of amorphous silicon (amorphous silicon) thin film cells is 10.1%

A solar cell is an optoelectronic device that converts energy into electricity. Semiconductor "silicon" is the most basic material, it is not conductive, but if mixed with different impurities in the semiconductor, can make a p-type and n-type semiconductor, reuse of p-type semiconductor has a hole (p-type semiconductor a negatively charged electrons, less visible as a positive charge), and the N type semiconductor one more free electrons of the potential to generate an electric current, so when the sun light energy will be an electron out of the silicon atoms, and electrons and holes of convection, the electrons and holes will be affected by the built-in potential, attracted to n-type and p-type semiconductors, respectively, and gathered at both ends. At this point, if external electrodes are connected, a loop is formed, which is how solar cells generate electricity.

To put it simply, the principle of solar photovoltaic power generation is to use solar cells to absorb the sunlight of 0.4-1.1 wave m (for silicon crystals), and convert the light energy into electricity output.