Superhot Rock Geothermal:
A Vision for Zero-Carbon Energy “Everywhere”
Clean Air Task Force
October 2021
Superhot rock (SHR) has been called the “holy grail” of geothermal energy—because, in most of the world, SHR could provide competitive, zero-carbon, dispatchable power and support zero-carbon hydrogen fuel production. It is one of the very few high-energy-density, zero-carbon resources that could replace fossil energy around the globe.
In SHR systems, water is injected deep underground into a superhot heat reservoir and then is returned to the surface as superhot steam to power steam generators. Several R&D projects around the world have already drilled into superhot rock and have begun developing methods for operating in these extreme heat and pressure conditions. While superhot steam has yet to be harnessed for power production, its high energy potential is clear.
To realize the full potential of SHR, significant engineering innovations will be required like super-deep drilling, heat resistant well materials and deep heat reservoir development. But these are engineering challenges, not needed scientific breakthroughs. Intensive drilling campaigns, incorporating innovations from unconventional oil and gas experience, could drive rapid learning to address these engineering obstacles and drive further cost reductions. Big tech could also speed SHR by supporting energy drilling ventures or by providing power purchase agreements for successful projects. With significant private and public investment, along with enabling policies and continued technological innovation, SHR could plausibly be commercialized within 10 to 15 years.
John Herter and Eric Ingersoll of LucidCatalyst contributed to this important Clean Air Task Force (CATF) report.