Concentrating Solar Power (CSP), to be precise, should be “Concentrated Solar Thermal Power Generation”. Refers to a power generation method that uses a certain kind of radiant energy concentrator to focus the radiant energy of the sun, heat the working fluid, and deliver heat through the working fluid to generate high-temperature steam to drive the generator driven by the steam turbine to generate electricity.
Concentrated solar power technology (CSP; this definition does not include concentrated photovoltaic power generation technology (CPV). Concentrated solar power generation is different from solar photovoltaic power generation. Solar cells use solar panels and use the photovoltaic effect to directly convert solar radiant energy into electrical energy. It can be operated on cloudy days. Generally, CSP can only be carried out in sunny and sunny places. However, even at night when there is no sun, using a large enough molten salt storage tank to store heat can solve the problem of all-weather power supply. ) Can convert solar radiation into heat energy, and then generate steam to drive the generator. In addition, this technology can also be used in conjunction with an external combustion engine/generator. As described below, this technology has reached the scale of electricity consumption for public utilities, and a single CSP system can directly use (beam) solar radiation to generate up to hundreds of megawatts of electricity. The collector uses different methods to concentrate solar radiation. After receiving the concentrated solar radiation, its working temperature can rise to 500°C~1,000°C (Figure 1). Hundreds to thousands of heliostats (2-axis tracking solar reflectors) are scattered around the solar power tower. These mirrors reflect solar radiation to the receiver on the central tower. The receiver is an efficient heat exchanger that uses molten salt as the working medium. After receiving the heat energy, the working medium stores it in a large tank, and then the heat is used to drive the turbine generator. This process is the same as the traditional one. Fossil combustion power generation is similar. According to the type of reflector, it can be divided into groove type, butterfly type, Fresnel prism type, and groove type application technology is the most mature.
The basic principle of the linear trough collector technology is that a parabolic reflector or a set of Fresnel reflectors are installed on a 1-axis solar tracker, and the solar radiation is focused by the tracker to the focal line position of the collector On the receiver absorber tube. Heat collectors are usually placed in the form of north-south, which can rotate from east to west with the sun during the day, so as to continuously concentrate the direct solar radiation on the absorption tube. The heat-carrying fluid flows through the receiver absorption tube and then enters a series of heat exchangers to generate high-pressure superheated steam. Then the heat-carrying fluid returns to the receiver absorption tube, and the obtained steam is transferred to the steam turbine generator to generate electricity. The dish Stirling engine is installed at the focal position of the parabolic mirror, and is continuously aligned with the sun through a 2-axis tracker to achieve continuous operation. The heat-carrying fluid is heated to 250°C~700°C in the receiver, and then the external combustion type Stirling engine uses the heat in the fluid to generate electricity. The modular parabolic mirror system has high efficiency and can meet the needs of community distributed power generation and centralized power generation of public utilities. Like all concentrating solar power (CSP) technologies, the dish Stirling system also requires the resource information of direct solar (beam) radiation.
