Over the next few years, Calpine will develop more energy centers to power millions of homes and businesses using clean, reliable electricity. Because this technology is so preferable to that of older facilities, it has earned the support of health, safety, environmental and consumer groups. These centers use a highly fuel-efficient process that involves generating electricity in combustion turbines and utilizing the procedure's hot exhaust to create water vapor, which is then used to generate additional electricity in a steam turbine. The world's largest geothermal operation is The Geysers, about 100 miles north of San Francisco in the Mayacamas Mountains.
Geothermal power is natural.
It occurs when water deep below the earth's surface is heated by exposure to hot porous rock, and the resulting dry steam moves to the surface through geologic faults and bursts forth in the form of fumaroles, which are not true geysers despite the common reference. As the heated steam moves close to the surface, it can be run directly into a conventional steam turbine generator to create electricity. Wells, some greater than two miles deep, have been drilled to tap this natural steam. At The Geysers, the captured steam is piped to generating units. The steam spins a turbine that drives a generator to produce much-needed electricity for the California power market.