Below the surface of the Salton Sea in California’s southeastern desert lies one of the world’s largest sources geothermal energy—where the earth’s heat and pressure create hot water and steam all day long. Now two start-up firms have announced plans to build the nation’s largest geothermal power plant that will harvest this natural heat and convert it into electricity using steam turbines. As well as producing clean energy, the geothermal plant will also play host to a mining operation that would begin extracting lithium carbonate—used for the batteries of electric cars—as well as manganese, zinc and other minerals in 2019. The geothermal power plant could go online as early as 2020 and would generate nearly six times the electricity as similar facilities in the area.