First Unit of Commercial Geothermal Power Plant Completed in Idaho

December 31, 2007

U.S. Geothermal Inc. announced in late December that it has completed Unit One of its binary cycle geothermal power plant at Raft River, Idaho, about 200 miles southeast of Boise. When fully completed, the plant will be the first commercial geothermal power plant in the Pacific Northwest, with the potential to generate 100 megawatts (MW) or more of electricity.

Unit One will be capable of producing 13 MW of electricity, but currently is producing between 8 and 9 MW. The unit is being tested while U.S. Geothermal operators learn about each well's capabilities and the relationship of injection pressure to production.

Test power is being purchased at a reduced rate by Idaho Power Company under the terms of a 10-MW Public Utility Regulatory Policies Act (PURPA) contract. The utility will pay full price when the unit achieves commercial operation mode, pending approval of a new contract by the Idaho Public Utility Commission.

The power plant site covers 8.2 square miles and includes four production wells and three injection wells. According to independent consultant GeothermEx Inc., of Richmond California, the Raft River site has a potential capacity of 15.6 MW per square mile, which may translate to 100 MW or more.

Boise-based U.S. Geothermal received the Governor's Clean Energy Award in January 2007 for its work at the Raft River site, which has contributed to the development of renewable energy in Idaho.

For more information, see the U.S. Geothermal December 28 press release, distributed by Marketwire, and a January 2007 State Energy Program project brief.

To read more about renewable energy and energy efficiency projects in Idaho, see: