Daggett Solar Electric Generating Station, California

This is the first industrial-scale commercial solar plant built in the USA. It has a peak output of 45 megawatts, and was built in the mid-1980s. Known as SEGS 1 and 2, this was the first of three separately owned sites within 40 miles of one another that make up the nine solar fields in the Solar Electric Generating System (SEGS), with SEGS 3-7 at Kramer Junction, and SEGS 8 and 9 at Harper Lake. These are not photovoltaic plants. They operate using rows of parabolic mirrored troughs, which focus the sun onto glass tubes, through which a heat transfer medium flows. The hot liquid is pumped to steam generators, which produce electricity. Built in response to the energy crisis of the late 1970s, and finally going online in the 1980s, the three SEGS sites had a peak capacity of more than 350 megawatts, and comprised all of the industrial-scale solar power produced in the USA for nearly 20 years. Starting around 2010, more large-scale solar power generating stations have been built, and there are now dozens in the southwestern USA producing more than 100 megawatts each.