There’s enough geothermal energy below ground to power the entire country. Some are trying to tap it — by using techniques from the fracking boom.
Brad Plumer traveled to Beaver County, Utah to visit geothermal projects there and spoke with dozens of people involved in the industry.
In a sagebrush valley full of wind turbines and solar panels in western Utah, Tim Latimer gazed up at a very different device he believes could be just as important for fighting climate change.
It was a drilling rig, of all things, transplanted from the oil fields of North Dakota. But the softly whirring rig wasn’t searching for fossil fuels. It was drilling for heat.
Mr. Latimer’s company, Fervo Energy, is part of an ambitious effort to unlock vast amounts of geothermal energy from Earth’s hot interior, a source of renewable power that could help displace fossil fuels that are dangerously warming the planet.
“There’s a virtually unlimited resource down there if we can get at it,” said Mr. Latimer. “Geothermal doesn’t use much land, it doesn’t produce emissions, it can complement wind and solar power. Everyone who looks into it gets obsessed with it.”
Traditional geothermal plants, which have existed for decades, work by tapping natural hot water reservoirs underground to power turbines that can generate electricity 24 hours a day. Few sites have the right conditions for this, however, so geothermal only produces 0.4 percent of America’s electricity currently.
Dozens of geothermal companies have emerged with ideas.
Fervo is using fracking techniques — similar to those used for oil and gas — to crack open dry, hot rock and inject water into the fractures, creating artificial geothermal reservoirs. Eavor, a Canadian start-up, is building large underground radiators with drilling methods pioneered in Alberta’s oil sands. Others dream of using plasma or energy waves to drill even deeper and tap “superhot” temperatures that could cleanly power thousands of coal-fired power plants by substituting steam for coal.
Still, obstacles to geothermal expansion loom. Investors are wary of the cost and risks of novel geothermal projects. Some worry about water use or earthquakes from drilling. Permitting is difficult. And geothermal gets less federal support than other technologies.
“Everyone knows about cost declines for wind and solar,” said Cindy Taff, who worked at Shell for 36 years before joining Sage Geosystems, a geothermal start-up in Houston. “But we also saw steep cost declines for oil and gas drilling during the shale revolution. If we can bring that to geothermal, the growth could be huge.”
Near the town of Milford, Utah, sits the Blundell geothermal plant, surrounded by boiling mud pits, hissing steam vents and the skeletal ruins of a hot springs resort. Built in 1984, the 38-megawatt plant produces enough electricity for about 31,000 homes.
The Blundell plant relies on ancient volcanism and quirks of geology: Just below the surface are hot, naturally porous rocks that allow groundwater to percolate and heat up enough to create steam for generating electricity. But such conditions are rare. In much of the region, the underground hot rock is hard granite, and water can’t flow easily.
This is “enhanced geothermal,” and people have struggled with the engineering difficulties since the 1970s.
Mr. Latimer seemed less surprised. Before founding Fervo in 2017, he worked as a drilling engineer for BHP, an oil and gas firm. There, he became convinced that previous attempts at enhanced geothermal failed because they hadn’t taken advantage of oil and gas innovations like horizontal drilling or fiber-optic sensors.
“If we had to invent this stuff ourselves it would have taken years or decades,” Mr. Latimer said. “Our big insight was that people in geothermal simply weren’t talking enough to people in oil and gas.”
Research at FORGE could help. Drilling deeper and hotter can make projects more cost-effective, since more heat means more energy. But existing oil and gas equipment wasn’t designed for temperatures above 350 degrees, so FORGE is testing new tools in hotter rock.
“No one else is willing to take the risks we can take,” said Joseph Moore, a University of Utah geologist who leads FORGE.
“If we can find it, we have a pretty big appetite for geothermal,” said Ted Bardacke, Clean Power Alliance’s chief executive. “We’re adding more solar every year for daytime and have a huge build-out of batteries to shift power to the evening. But what do we do at night? That’s where geothermal can really help out.”
Fervo faces fierce competition for the future of geothermal.
“If geothermal is ever going to scale, it has to be a repeatable process you can do over and over,” said John Redfern, Eavor’s chief executive. “We think we’ve got the best way to do that.”
“The ultimate goal should be to get to the superhot stuff,” said Bruce Hill of the Clean Air Task Force, an environmental group.
“There are huge engineering challenges,” said Carlos Araque, Quaise’s chief executive.
“But,” he added, “imagine if you could drill down next to a coal plant and get steam that’s hot enough to power that plant’s turbines. Replacing coal at thousands of coal plants around the world. That’s the level of geothermal we’re trying to unlock.”
“It’s been hard for geothermal to fight its way into the conversation,” said Jamie Beard, founder of Project InnerSpace, a Texas-based nonprofit that promotes geothermal.
“Historically, the upfront costs and risks of geothermal have been challenging,” said Ajit Menon, vice president for geothermal at Baker Hughes. “But we think it’s got a huge role to play. And we have workers with the right skills, the right technology. You can see why it makes sense for us.”
Source: NYTimes Science