The results of two enhanced geothermal flow tests shared this month indicate that significant advancements in this emerging arena are underway.
This month, Fervo Energy announced record-breaking flow rates during the first well test at its enhanced geothermal system (EGS) project, Cape Station, in southern Utah.
The 30-day test produced over 10 MW of electricity—tripling the output of a typical production well compared to Fervo's first commercial pilot, Project Red in Nevada, which generated 3.5 MW during its 2023 test. Houston-based Fervo achieved this with a peak flow rate of 107 kg/sec of high-temperature water.
While specific figures on production volumes or temperature were not disclosed, Fervo previously indicated that its production wells are expected to see flow rates between 50,000 and 100,000 BWPD at approximately 400°F.
With a successful test in hand, the company has declared Cape Station as the most-productive EGS project to date. Plans call for the project to begin supplying up to 90 MW of grid power by 2026, with 400 MW contracted and set to be supplied by 2028.
“Fervo continues to achieve technical milestones for geothermal development that experts predicted to be set decades from now,” said Tim Latimer, Fervo CEO and cofounder, in a statement.
The EGS approach is distinct from traditional geothermal systems due to its use of horizontal drilling and hydraulic fracturing. With optimal well spacing, this combination creates extensive flow paths between injection and production wells. Energy is extracted from the hot water using generators equipped with closed-loop turbines.
Fervo has drilled 15 wells at Cape Station over the past year, with plans to drill up to 29 in total. The company also recently secured a $100-million loan to support its construction efforts at the site.
Fervo highlighted that oil and gas workers account for 90% of the labor hours at Cape Station. The company aims to expand this workforce by forming stronger ties with oilfield services companies in Utah.
Fervo’s progress follows earlier comments from its chief technology officer, Jack Norbeck, who described the firm as having "reached the Mitchell Energy moment"—a reference to the firm helmed by the late George Mitchell, widely regarded as the pioneer of the shale revolution.
The company also noted that its well test has achieved the advanced technology targets established by the US National Renewable Energy Laboratory (NREL), goals that were initially not expected to be met until 2035.
Jeff Marootian, principal deputy assistant secretary for the US Department of Energy (DOE), which oversees NREL, said Fervo has shown that EGS is nearing commercial viability. “It’s this type of literal ground-breaking achievement that is paving the way to expand geothermal energy and realize its crucial role in our clean energy future,” he said.
Not far from Cape Station, the DOE-backed Utah Frontier Observatory for Research in Geothermal Energy (FORGE) project completed its own month-long test, according to a release also published this month. The test achieved a steady injection rate of 420 gal/min (10 bbl/min) with over 90% of the produced water recovered at temperatures around 370°F.
The Utah FORGE team noted on its website, “The results provide positive indications of the long-term behavior of the reservoir and the amount of heat that can be extracted.”
The research group used a wide array of diagnostics during the test, including tracers and microseismic geophones installed in nearby monitoring wells.
Fiber-optic cables were also installed in wells to measure microsesimicity, temperature, rock strain, and pressure. This was followed by downhole surveys conducted to analyze wellbore conditions.
FORGE is still reviewing the data from the test, which was completed in August. The results will be added to the group’s public database once finalized, and longer-term tests are planned, though no timeline has been provided.
The August flow test follows a smaller but similarly successful circulation test conducted by FORGE in May. The 9-hour test used injection rates of up to 15 bbl/min and resulted in an output of 8 bbl/min from the production well, achieving an efficiency rate of 70%. The test also recorded an outflow temperature of nearly 282°F.
