Photovoltaic power generation is based on the principle of the photo-ford effect, using solar cells to directly convert solar energy into electrical energy. Whether used alone or connected to the grid, the photovoltaic power generation system is mainly composed of solar panels (modules), controllers, inverters, and mainly electronic components, without mechanical components. Therefore, photovoltaic power generation equipment is extremely delicate, reliable, stable, long-life, and easy to install and maintain. In theory, photovoltaic power generation can be used anywhere that electricity is needed, from spacecraft to homes, from megawatts to toys. The efficiency of domestic crystalline silicon cells is about 10% to 13%, and the efficiency of similar foreign products is about 12% to 14%. A solar panel consisting of one or more solar cells is called a photovoltaic module.
The solar photovoltaic power generation system consists of solar cells, solar controllers and batteries (groups). If the output power is AC 220V or 110V, an inverter is also required. The functions of each part are:

(1) Solar panels: Solar panels are the core part of the solar power generation system and the most valuable part of the solar energy system. Its function is to convert the radiation power of solar energy into electrical energy, or to transfer it to the battery for storage, or to drive the load to work.

(2) Solar controller: The function of the solar controller is to control the working state of the entire system and prevent the battery from overcharging and over-discharging. When the temperature difference is large, a qualified controller should also have a temperature compensation function. Other additional functions, such as light-controlled switches, time-controlled switches, etc., are optional for the controller;

(3) Storage battery: Generally a lead-acid battery. In small and micro systems, nickel-metal hydride batteries, nickel-chromium batteries or lithium batteries can also be used. Its job is to store the electricity generated by the solar panel when it is exposed to light and release it when needed.

Inverter: The direct output of solar energy is 12VDC, 24VDC, 48VDC. In order to power 220VAC appliances, the direct current generated by the solar power generation system needs to be converted into alternating current, so a DC-AC inverter is required.