Hot Dry Rock Geothermal Prospects, 1981

Abstract

The hot dry rock (HDR) site selection and resource evaluation team at Los Alamos National Laboratory has been assessing roughly 24 sites within the USA as candidates for development of a second HDR geothermal system. Potential sites we have examined fall broadly into three thermal anomalies: 1. Quaternary magmahydrothermal (volcanic or igneous) systems such as the Geysers - Clear Lake region, California, 2. regional thermal anomalies of tectonic origin such as the Basin and Range Province of the Southwest, and 3. pre-Quaternary plutonic and metamorphic complexes such as the Conway Granite, New Hampshire. Although sites with both electrical generation and direct use potential have been considered, DOE has directed us to concentrate our efforts on electrical sites. Criteria for a successful HDR electrical generation site utilizing current technology require temperatures >200°C, depth < 5/km, and impermeable reservoir rocks. Site with these characteristics only exist in the western USA. The significance of other criteria such as environmental issues, water rights, public visibility, and preexisting power networks have not yet been evaluated.