The Geysers
The Geysers, a geothermal power field of 72 miles (116 km) north of San Francisco, California, is the largest geothermal development in the world. It produces over 750 MW.  The Geysers has 22 separate power plants that use steam from more than 350 producing wells.  The Calpine Corporation operates and owns 19 of the 22 facilities.