Solar thermal power generation is a power generation technology that converts solar radiation energy into electrical energy. It includes two types:
①Using solar thermal energy to directly generate electricity, such as thermoelectric power generation of semiconductor or metal materials, thermal electron and thermionic power generation in vacuum devices, thermoelectric conversion of alkali metals, and magnetic fluid power generation.
②Solar thermal power generation, using solar collectors to collect solar energy, heating water or other working fluids to generate steam, driving heat engines, and then driving generators to generate electricity. That is, this type first converts thermal energy into mechanical energy, and then converts mechanical energy into electrical energy.
The working principle of the solar thermal power generation system is basically the same as that of the conventional thermal power generation system. The fundamental difference lies in the different heat sources. The former uses solar energy as the heat source, while the latter uses fossil fuels such as coal, oil and natural gas as the heat source. In a conventional thermal power plant, coal or oil is supplied to the boiler for combustion, and the heated water is turned into superheated steam to drive a turbine generator set to generate electricity, thereby converting thermal energy into electrical energy. Thermodynamically, this conventional thermal power generation works according to the Langqing cycle principle, as shown in Figure 1.
Figure 2 shows the principle of the thermal cycle system of a typical solar thermal power station.
Comparing Figure 1 and Figure 2, it can be clearly seen that the thermodynamic cycle systems of conventional thermal power plants and solar thermal power plants are basically similar, and their steam turbine power generation parts are exactly the same, both generating superheated steam to drive the steam turbine generator set to generate electricity; the difference lies in the use of different primary energy sources.
Classification of solar thermal power generation
Solar power generation technologies are divided into direct solar power generation and indirect solar
Solar power generation technologies are divided into direct solar power generation and indirect solar power generation.
Direct solar power generation is divided into solar photovoltaic power generation and solar light induction power generation; solar indirect power generation includes solar thermal power generation, solar photochemical power generation and solar photobiological power generation.
Solar thermal power generation: direct solar thermal power generation, solar thermal indirect power generation.
Solar thermal direct power generation: solar thermal thermoelectric power generation; solar thermal photovoltaic power generation; solar thermal ion power generation.
Solar thermal indirect power generation: non-concentrating solar thermal power generation (including solar thermal airflow power generation, solar pool thermal power generation) and concentrated solar thermal power generation (including dish solar power generation, tower solar power generation, trough solar power generation).