The United States continues to lead the world in installed geothermal power capacity as well as in electrical generation producing 16,000 GWh/yr from 2,212 MWe capacity for a load factor of 0.83%. However, geothermal energy is a small contributor to the electric power capacity and generation in the United States.
In 1998, geothermal plants constituted about 0.25 percent of the total operable power capacity. In 1998, those plants contributed 0.38 percent of the total generation and, for 2000, it stands at 0.45 percent.
On a state level, geothermal is a major player in California and Nevada. It is a minor source of power in Hawaii and Utah. Further, it has the potential to become significant on the Big Island of Hawaii and perhaps, in the future, the Pacific Northwest.
The most impressive geothermal growth in the United States occurred during the 1980s, with an average annual increase in capacity of about 11 percent. In contrast, from 1990-2000, it has averaged only one percent due to a leveling off of new plant construction. This recent period also saw a reduction at The Geysers in California to an operating capacity of about 1,137 MWe, down from a total installed capacity of 1,989 MWe.
Contributing to the capacity stagnation are the decline in steam production, and the retirement and shut down of six units at The Geysers in California. These include the four original units (78 MWe), both the Central California Power Agency (CCPA) units (130 MWe), and the 55 MWe Bottle Rock plant. However, the Bottle Rock plant has been purchased by ThermaSource, Inc. and should start operation by the summer of 2001. CalEnergy has completed Unit 5, a 49-MW facility and a 10-MW turbine at the Salton Sea in mid 2000.
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