Application of solar cell
Solar cells are devices that respond to light and convert light energy into electricity. There are many kinds of materials that can produce photovoltaic effect, such as single crystal silicon, polycrystalline silicon, amorphous silicon, gallium arsenide, selenium, indium. copper and so on. Their power generation principles are basically the same. Now we take crystal as an example to describe the process of optical power generation. P type crystalline silicon can get N type silicon and form P-N junction by doping phosphorus.
When the light is irradiated on the surface of a solar cell, a part of the photon is absorbed by the silicon material; the energy of the photon is transferred to the silicon atom, which makes the electrons migrate and becomes a free electron on both sides of the PN junction to form a potential difference. When the external circuit is connected, the current will flow through the external circuit to produce one. The output power is fixed. The essence of this process is the process of converting photon energy into electrical energy.