Hot Dry Rock Geothermal Energy in the USA - Moving Toward Practical Use

Abstract

The technology for extracting geothermal energy from the vast hot dry rock (HDR) geothermal resource has been under development by the Los Alamos National Laboratory for about 25 years. In 1992-1993, an extensive flow-testing program was conducted at the Fenton Hill, New Mexico HDR Test Facility. During two segments of this test, energy was produced at a rate of 4 thermal megawatts on a continuous basis for periods of 1 and 55 days, respectively. Surface and logging measurements showed no decline in the temperature of the water produced from the HDR reservoir during the flow testing. In fact, tracer evidence indicated that the circulating water was continually gaining access to additional hot rock as the testing proceeded. Water consumption was low and all other test data were positive. The encouraging results of the flow testing at Fenton Hill provided the incentive for the United States Department of Energy (USDOE) to solicit the interest of private industry in a jointly funded program to construct and operate a facility that would produce and sell energy derived from HDR resources. A number of organizations responded positively. On the basis of the interest expressed in these responses, the USDOE subsequently authorized the issuance of a formal solicitation to initiate the project.