Fervo Energy Sets Record With New Enhanced Geothermal Well

Fervo Energy announced the successful drilling and logging of its Sugarloaf appraisal well in southwest Utah, an operational achievement that the company said demonstrates the rapid advancement and scalability of enhanced geothermal systems (EGS). The well was drilled to a true vertical depth of 15,765 feet and is projected to reach a bottomhole temperature of 520F after full thermal equilibration. Houston, Texas-based Fervo, in announcing the successful project on June 10, said the Sugarloaf well was completed in just 16 drilling days, representing a 79% reduction in drilling time compared to the U.S. Department of Energy baseline for ultradeep geothermal wells.

While drilling what is Fervo’s hottest and deepest well to-date, the company was able to achieve multiple drilling performance records, including a maximum bit run length of 3,290 feet, a maximum average rate of penetration, or ROP, of 95 feet/hour, and an instantaneous ROP of more than 300 feet/hour at depths greater than 15,000 feet. These results expand the window for commercial viability of EGS into a significantly deeper and hotter regime, paving the way to deploy the technology outside of the western U.S.

In parallel, Fervo has obtained an independent geothermal reserves report from worldwide consulting firm DeGolyer & MacNaughton for Cape Phase I. This comprehensive technical and economic evaluation of Fervo’s development plan provides external verification on Fervo’s ability to deliver contracted clean energy volumes to customers, including Shell Energy and Southern California Edison.

DeGolyer & MacNaughton’s independent estimates of heat-in-place and reserves involved a comprehensive review of Fervo’s drilling data, geologic models, and production test results. The report highlights that Fervo’s proprietary EGS design successfully unlocks thermal recovery factors in the range of 50% to 60%, tripling the amount of useful thermal energy reserves compared to conventional geothermal technology. The report confirms that the Cape Station project area can support more than 5 GW of development at depths of up to 13,000 feet. The new Sugarloaf drilling results are expected to increase Cape’s resource potential even further.

Various geothermal resource evaluation and grid modeling studies—including recent reports by the U.S. Geological Survey, Princeton University, and National Renewable Energy Laboratory—have now aligned that there are hundreds of gigawatts of opportunity for geothermal deployment in the range of 10,000 to 20,000 feet and 400F to 600F.

“Back in July 2020, we performed our first EGS field trials at reservoir temperatures of around 300F,” said Jack Norbeck, CTO and co-founder of Fervo Energy. “In just a few years, we’ve developed innovations that enable our technology to operate reliably at temperatures exceeding 500F. These drilling results demonstrate that Fervo is operating in the optimal geothermal conditions for large-scale commercial deployment.”

Fervo has said the ability to unlock firm, carbon-free energy from heat reservoirs miles underground will be critical to meet growing U.S. power demand driven by artificial intelligence, electrification, and grid reliability needs.

—POWER edited this content, which was contributed by Fervo Energy.