Performance and operational experience of a prototype binary geothermal power plant

At the Raft River geothermal site in south central Idaho, the Idaho National Engineering Laboratory is investigating and demonstrating the production of electrical power from a moderate temperature (140/sup 0/ to 145/sup 0/C) geothermal resource. The initial production of electrical power at the Raft River site was accomplished with the Prototype Power Plant which was built to investigate and demonstrate the operation of binary power cycles where the energy in the geothermal fluid is transferred to a secondary working fluid. This plant serves as a test bed for testing pilot scale components, systems, and/or concepts that have the potential for enhancing the feasibility of power generation from moderate temperature geothermal resources. During the automatic run test the plant was able to produce a maximum of 59kW(e). Although the plant was not (and has not) operated at design turbine conditions, performance was predictable. During the automatic run test, the plant operation was stable and the facility was operated for 1357 hours producing electrical power approximately 87% of the time geothermal fluid was available for operation