Project Information

An Impressive Feat of Engineering

The Coso Operating Company geothermal facility, nine geothermal plants on U.S. Navy-owned land abutting China Lake, produces about 145 net megawatts (MW) of power to Southern California Edison. To put that in perspective, a single megawatt has enough electricity to provide power to roughly 1,000 homes. The pipes enter each power station, weaving into steam turbines. The turbines are coupled to generators, and turn at about 3,600 rpm, producing 13,800 volts of electricity. Geothermal reservoir source has been consistent at 600˚F (almost 3 times boiling point). The plants were constructed from 1987 to 1989, and currently use about 105 production wells to capture underground steam that steam turbines then transform into electricity. The first of the facility’s four power plants eventually went online in May of 1987. Each power plant now produces almost equal amounts of power.

Coso Geothermal Power Plants

  • Navy-I (3 turbine/generator units)
  • Navy-II (3 turbine/generator units)
  • BLM East (2 turbine/generator units)
  • BLM West (1 turbine/generator units)
  • Navy-I generates power at 115kV level
  • Navy-II and BLM generate power at 230 kV level

The Wellfield

  • 105 Production wells (range between 2,500 and 13,000 feet deep)
  • 34 Injection wells


  • 80 Coso Operating Company Employees located on site