Solar thermal power generation systems collect and concentrate sunlight to produce the high temperature heat needed to generate electricity. All solar thermal power systems have solar energy collectors with two main components: reflectors (mirrors) that capture and focus sunlight onto a receiver. In most types of systems, a heat-transfer fluid is heated and circulated in the receiver and used to produce steam. The steam is converted into mechanical energy in a turbine, which powers a generator to produce electricity.
Solar thermal power systems may also have a thermal energy storage system component that
allows the solar collector system to heat an energy storage system during the day, and the
heat from the storage system is used to produce electricity in the evening or during cloudy
weather. Solar thermal power plants may also be hybrid systems that use other fuels (usually
natural gas) to supplement energy from the sun during periods of low solar radiation.