Utilization of U. S. geothermal resources. Final report

This study is concerned with U.S. geothermal resources, their potential for commercial utilization by electric utilities between now and the year 2000, and their impact on the utility industry. USGS estimates of the resources in identified hydrothermal systems were extrapolated to the undiscovered resources marked by hot springs, and further to the blind resources between hot spring areas within the tectonic belts. The resulting estimate of the total hydrothermal resource to a depth of 10,000 ft. is about 100,000 MWe for 30 years with about one-half in undiscovered blind resources, one-fourth in undiscovered hot spring resources, and one-fourth in identified systems. Water rates and direct capital costs for geothermal power plants were evaluated as functions of resource temperature, together with costs and expected flowrates for geothermal wells. Combining these results with the temperature distribution of identified hydrothermal systems, a current supply curve for geothermal energy wa s made. This shows an estimated 20,000 MWe for 30 years potentially producible with current technology from identified resources for direct capital costs of $800/KW or less. The projected supply curve shows an estimated 30,000 to 60,000 MWe for 30 years potentially available at $800/KW or less, in 1976 dollars, taking account of estimated undiscovered resources and probable technical advances.