The first commercial-scale concentrated solar thermal power plant with central receiver tower technology, 140 m high, heliostat field and molten salt thermal storage system. Located in the municipality of Fuentes de Andalucía (Seville), it has a 195-hectare solar field which includes 2,650 heliostats, adding up to a total reflecting surface area of 304,750 m2. The technology used at Gemasolar allows it to produce 100% solar electricity for 15 hours in the absence of the sun, even at night, with a power output of 17 MWh and generating around 80 GWh per year, which is equivalent to saving 30,000 tonnes of CO2 emissions per year. The heat collected by the salts, which can reach temperatures of around 570ºC, is used to generate high-pressure, high-temperature steam, which is used to produce electricity. The surplus heat accumulated during the hours of solar radiation is stored in the hot salt tank, giving the plant the capacity to produce electricity 24 hours a day for most of the year.