The Geysers

About Geothermal Energy

Welcome to The Geysers

About Geothermal
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In the Mayacamas Mountains, located north of San Francisco, naturally occurring steam field reservoirs below the earth's surface are being harnessed by Calpine to make clean, green, renewable energy for homes and businesses across Northern California.

The Geysers, comprising 45 square miles along the Sonoma and Lake County border, is the largest complex of geothermal power plants in the world. Calpine, the largest geothermal power producer in the U.S., owns and operates 15 power plants at The Geysers with a net generating capacity of about 725 megawatts of electricity - enough to power 725,000 homes, or a city the size of San Francisco.

The Geysers meets the typical power needs of Sonoma, Lake and Mendocino counties, as well a portion of the power needs of Marin and Napa counties. In fact, The Geysers satisfies nearly 60 percent of the average electricity demand in the North Coast region from the Golden Gate Bridge to the Oregon border. The Geysers is one of the most reliable energy sources in California, delivering extremely high availability and on-line performance, and accounts for one-fifth of the green power produced in California.

Geothermal power is energy derived from the heat of the earth's core. "Geo" means "from the earth" and "thermal" means "heat." This type of energy is clean and predictable, offering a reliable and renewable energy source.

The Special Properties of Geothermal Sites

Drill deep enough and the earth is hot everywhere, but converting that heat to power is a challenge. Sites such as The Geysers, where the heat is close to the surface and deep rock layers are fractured to allow water to percolate through, are quite rare.