Advances in binary-cycle power and submersible pump technologies over the past two decades have made electric power generation from geothermal fields in the moderate temperature range (100° to 180°C) convincingly commercial. For geothermal water in this temperature range, binary-cycle is more efficient for power conversion than flash-cycle and pumping of wells is more efficient than self flowing. The lower temperature limit of 100°C is imposed by the limits of binary-cycle technology and the upper limit of 180°C is imposed by the limits of pump technology commercially available today. This paper is a case study of optimization of net power generation from such a field at Raft River, in the State of Idaho, United States.

This report presents the" results of the California Division of Mines and Geology's (COM G) geothermal resource investigation of the Paso Robles area, California. The study was undertaken to learn more about the known geothermal resource In this area and to assess the potential of the resource for development and use by the local community. The project was conducted in compliance with the terms of the fourth-year contract (1981-82) with the U.S. Department of Energy (DOE) under the state-coupled program and performed under CDMG's Phase II site-specific geothermal resources studies program.

The California Division of Mines and Geology (CDMG) selected the San Bernardino area for detailed geothermal resource investigation because the area was known to contain promising geothermal resource sites, the area contained a large population center, and the City of San Bernardino had expressed serious interest in developing the area's geothermal resource.