 In general, the Geysers has  of active installed capacity with an average production factor of 63% (955 MW).Of nearly two dozen active plants in the Geysers in 2013, Calpine Corporation operated 19 plants in 2004 but only 15 in 2013.Two other plants are owned jointly by the Northern California Power Agency and the City of Santa Clara's municipal Electric Utility (now called Silicon Valley Power).