What are the ways of solar power system
Solar power generation methods include solar photopower and solar thermal power
1. Solar photovoltaic power generation
Solar photopower generation refers to a power generation method that converts light energy directly into electricity without a thermal process. It includes photovoltaic power generation, photochemical power generation, photoinduction power generation and photobiological power generation.
Photovoltaic power generation is a direct power generation method that uses solar level semiconductor electronic devices to effectively absorb solar radiation energy and convert it into electric energy. It is the mainstream of solar power generation today. In photochemical power generation, there are electrochemical photovoltaic cells, photoelectrolysis cells and photocatalytic cells. At present, photovoltaic cells are actually used.
The photoelectric conversion efficiency of monocrystalline silicon solar cell is about 15%, up to 23%, which is the highest in the solar cell photoelectric conversion efficiency, but its manufacturing cost is high. The service life of monocrystalline silicon solar cells is generally up to 15 years and up to 25 years.
Polysilicon solar cells are widely developed because they are cheaper to make than monocrystalline solar cells, which have a photoelectric conversion efficiency of 14 to 16 percent. However, the service life of polysilicon solar cells is shorter than that of monocrystalline solar cells.
2. Solar thermal power generation
Solar thermal power generation is a way of converting solar radiation into electricity through water or other working materials and devices.
First, the solar energy is converted into heat energy, and then the heat energy is converted into electric energy. There are two ways to convert the solar heat energy directly into electric energy. One is to convert the solar heat energy directly into electric energy, such as the power generation by the temperature difference of semiconductor or metal materials, the power generation by thermo electrons and thermo ions in vacuum devices, the thermoelectric conversion of alkali metals, and the power generation by magnetic fluid.
Another way is to run the sun's heat through a heat engine, such as a steam turbine, to turn a generator into electricity, similar to conventional thermal power, except that instead of fuel, the heat comes from the sun. There are many types of solar thermal power generation, mainly including the following five: tower system, trough system, disk system, solar pool and solar tower thermal power generation. The first three are concentrated solar thermal power systems, the last two are non-concentrated.
Some developed countries have taken solar thermal power generation technology as a national research and development focus and built dozens of demonstration solar thermal power stations of various types, which have reached the practical application level of grid-connected power generation.
At present, the most promising solar power system in the world can be divided into trough paraboloid focusing system, central receiver or solar tower focusing system and disk paraboloid focusing system.
The three technically and economically feasible forms are: 30 ~ 80MW focused parabolic trough solar thermal power technology (abbreviated as parabolic trough); 30 ~ 200MW point focused central receiving solar thermal power technology (referred to as central receiving); 7.5 ~ 25kW point focus parabolic disk solar thermal power generation technology (abbreviated as parabolic disk).