US Geothermal Progresses at Raft River Geothermal Plant

U.S. Geothermal recently completed drilling work on production well RRG-4, the construction site of its binary-cycle geothermal plant at Raft River in southeastern Idaho.

Subsequent flow test results show that RRG-4 will now be a substantial commercial production well feeding the Phase 1 power plant. The recent work on RRG-4 comes after the October 2006 deepening and testing of two injection wells that validated a reservoir model showing an extensive geothermal resource underlying the Raft River site. The company’s well-drilling operations have moved to RRG-3, where the well’s existing leg was deepened from 5,937 feet to 6,185 feet and a new second leg was drilled to a depth of 5,735 feet. “The results of the current drilling program are significant because we have shown that the hot geothermal reservoir extends all the way out to our planned injection well sites,” said Daniel Kunz, President and CEO of U.S. Geothermal Inc. Work on the Raft River power plant and pipeline continues on schedule. Ormat Nevada Inc., the contracting firm building the Raft River power plant, started fabrication in November of the Ormat Energy Converter; the first concrete for the cooling tower basin was placed and excavation work for the turbine/generator and condenser foundations has begun. And the Raft River Rural Electric Coop has begun construction of the 3.2-mile power line that will transmit power output from the project’s first phase to Idaho Power Company.