California Geysers geothermal expansion set

Calpine Corp., San Jose, Calif., plans a 2-year multirig drilling program to increase electricity production by as much as 80 Mw at its Geysers geothermal operation in northern California.

By OGJ editors
HOUSTON, June 1 -- Calpine Corp., San Jose, Calif., plans a 2-year multirig drilling program to increase electricity production by as much as 80 Mw at its Geysers geothermal operation in northern California.

The $200 million program is designed to expand dry steam production, identify new sources of geothermal power, and rebuild four older geothermal turbines to improve energy efficiency. Some of the new wells will be as deep as 11,000 ft.

The company said it will consider further development at Geysers Geothermal field if it is able to enter into long-term power sales contracts.

The field has 350 steam wells and 58 injection wells on 40 sq miles with 80 miles of steam lines. The operation, first drilled in 1954, is in the Mayacamas Mountains near Middletown, 70 miles north of San Francisco.

Calpine, which also operates gas-fired electric generating facilities, supports a state goal of obtaining 20% of its power from renewable sources by 2010.

Geysers, the world's largest geothermal operation, generates 725 Mw of electricity and represents 25% of California's renewable energy production and 40% of US geothermal electrical generation. Calpine owns 19 of the 21 geothermal units at the field. The generators connect with five major transmission lines that can deliver power statewide.

The project also recycles wastewater from nearby towns through the geothermal reservoirs for conversion into steam for electricity production.

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