Solar power station. Solar mirrors at Solar One, a power station at Barstow, California, USA, which operated between 1982 and 1988. A circular arrangement of 1,818 mirrors (heliostats) focused sunlight onto a central receiver on top of a 91- metre-high tower (upper right). The 7x7 metre square mirrors were computer-controlled to track the path of the Sun. Water passing through the receiver was heated to over 500 degrees Celsius and the resulting steam drove a turbine to produce electricity. Solar One was replaced in 1996 by a more efficient solar power station, Solar Two, which uses molten salt to store the Sun's energy.