The technology that revolutionized oil and gas production 15 years ago could be on the verge of turning hot rocks into a major source of green electricity. The U.S. Bureau of Land Management this month gave a green light to Houston-based Fervo Energy for its advanced geothermal project using modern oil and gas drilling tech on private, state, and federal land in Utah.
If successful, Fervo’s Cape Geothermal Power Project could generate up to 2,000-MW of baseload power on some 640 acres of Utah land (including 148 acres of Interior Department land), using directional drilling and hydraulic fracturing that transformed oil and gas production between 2008 and 2009. The technology expands the footprint of underground wells and breaks up tight rock formations, releasing fossil fuel or, in Fervo’s case, very hot rocks that can produce steam to turn electric turbines.
The description of the project in Beaver County from BLM’s Utah office demonstrates the scale of the venture: “Proposed activities include the development of an estimated 320 geothermal production and injection wells, up to 20 modular geothermal power plants, a power distribution system, an electrical switchyard, a general tie-in transmission line, geothermal fluid pipeline gathering system, associated access roads, and ancillary facilities such as pumping stations and required tie-in upgrades.”
In order to approve Fervo’s project, BLM had to conduct an environmental assessment under the terms of the National Environmental Policy Act (NEPA). The Interior Department agency produced a “Finding of No Significant Impact” for the Cape project. Gloria Tibbetts, district manager of BLM’s Color Country district found, “Based on my review of the Environmental Assessment and supporting documents, I have determined that the Proposed Action is not a major federal action and will not significantly affect the quality of the human environment.”
In August 2023, Fervo ran a successful 30-day well test at a site in northern Nevada. Fervo founder and oil and gas industry drilling veteran Tim Latimer said, “We employ precision directional drilling technology to drill horizontally in geothermal reservoirs. This enables us to drill multiple wells from a single location, dramatically lowering our surface footprint and reducing drilling risks. Horizontal drilling also facilitates greater access to geologies that were previously challenging to reach, increasing the total resource potential for geothermal energy.”
Fervo then fracks the rock to provide greater access to the heat they contain, injects water into the hot rocks, and captures the steam, running it through steam turbine generators. While fracking has created opposition in some oil and gas production regions, that opposition has not generated much traction, in part because many of the claims of damage, such as contaminating water wells, have proven bogus. Conventional water well companies have long used hydraulic fracturing of water-bearing rock strata. It’s a way to increase the water capacity in existing wells for rural farms and homes that rely on them for household and agricultural water.
That success led in February to Oklahoma-based oil and gas independent Devon Energy leading a $224 million funding consortium to invest in Fervo as it moves toward commercial operation. The Devon funding group includes Japan’s Mitsubishi Heavy Industries. At the same time, the Department of Energy awarded Fervo $25 million.
Fervo’s Latimer had worked as a drilling and completion engineer for BHP Billiton in Houston before founding Fervo in 2017. It was at BHP that he began thinking about using horizontal drilling to overcome the major problem with conventional geothermal, which has limited its ability to scale up commercially. Conventional geothermal projects drill vertical wells into often limited hot rock resources.
Latimer told Time, “Traditionally, you would drill simple vertical wells, and you would flow [water] between injection wells and production wells. What’s novel about our site is we drilled down about 8,000 ft., and then we turned and drilled horizontally for 4,000 ft. And then we flowed [water] from one horizontal well to the other across several hundred feet in that high temperature rock 8,000 ft. beneath our feet. That solves some of these economic challenges and allows us to go to deeper places and still make the economics work.”
At the same time the Utah BLM office was approving the Fervo project, the agency headquarters said the Biden administration is proposing a NEPA “categorical exclusion” for exploring for geothermal resources. A BLM press release said the exclusion “would apply to geothermal resource confirmation operations plan of up to 20 acres, which can include drilling wells (e.g., core drilling, temperature gradient wells, and/or resource wells) to confirm the existence of a geothermal resource, to improve injection support, or to demonstrate connections between wells. It will be published in the Federal Register in the coming days to begin a 30-day public comment period.”
BLM added, “Currently, geothermal developers must conduct two separate environmental reviews: one for initial exploration drilling and another to fully test the geothermal resource, even if both have similar environmental impacts. The proposal would apply only to geothermal resource confirmation operations on public lands and split estates. Further geothermal development would still require additional environmental analysis.”
–Kennedy Maize
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