Superhot Rock Geothermal Glossary

The document provides a comprehensive set of definitions for geothermal energy stakeholders, categorizing terms into internal heat, rock and fluid parameters, system types, locations, operations, and project finance. It emphasizes superhot rock (SHR) geothermal, which involves resources at or above 374°C, and distinguishes between conventional hydrothermal systems and unconventional methods like Enhanced Geothermal Systems (EGS) and closed-loop circuits. The glossary also outlines the technology readiness level (TRL) scale and the projected economic competitiveness of SHR at the Nth-of-a-kind scale.

• Supercritical fluids in superhot rock geothermal plays are modeled to transfer five to eight times more thermal energy to the Earth's surface than fluids used in conventional geothermal generation.
• Geothermal systems are classified by enthalpy; super-high-enthalpy systems, which include superhot rock geothermal plays, are characterized by reservoir temperatures exceeding 374°C and high pressure conditions.
• Superhot rock geothermal is expected to be economically competitive with other dispatchable and intermittent energy resources at the Nth-of-a-kind (NOAK) scale, with a preliminarily estimated Levelized Cost of Electricity (LCOE) between $20 and $35 per MWh.
• The document distinguishes between open-loop circuits, where subsurface working fluid has direct contact with rock pores and fractures, and closed-loop circuits, where the fluid remains inside deeply buried pipes.

APA

Banks, G., Ball, P., & Seligman, A. (2023). Superhot Rock Geothermal Glossary. Clean Air Task Force. https://www.catf.us/superhot-rock/glossary/

Chicago

Banks, Graham, Philip Ball, and Angela Seligman. Superhot Rock Geothermal Glossary. Clean Air Task Force, 2023. https://www.catf.us/superhot-rock/glossary/.

Wikipedia

{{cite report |last1=Banks |first1=Graham |last2=Ball |first2=Philip |last3=Seligman |first3=Angela |title=Superhot Rock Geothermal Glossary |publisher=Clean Air Task Force |date=14 February 2023 |url=https://www.catf.us/superhot-rock/glossary/ |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{banks2023superhot, author = {Banks, Graham and Ball, Philip and Seligman, Angela}, title = {{Superhot Rock Geothermal Glossary}}, institution = {Clean Air Task Force}, year = {2023}, month = feb, url = {https://www.catf.us/superhot-rock/glossary/}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }