BEAVER COUNTY, Utah – In a sagebrush valley full of wind turbines and solar panels in western Utah, Mr Tim Latimer gazed up at a very different device he believes could be just as powerful for fighting climate change – maybe even more.
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 produces only 0.4 per cent of America’s electricity.
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. “Geothermal has historically been overlooked,” Senator Lisa Murkowski, who represents Alaska, said at a hearing. But with innovation, she added, “the potential is out there, I think, that’s pretty extraordinary.”
Three miles east, two teams are trying to tap that hot granite. One is Utah Forge, a US$220 million research effort funded by the Energy Department. The other is Fervo, a Houston-based start-up. But in July, Forge announced it had successfully sent water between two wells. Two weeks later, Fervo announced its own breakthrough: A 30-day test in Nevada found the process could produce enough heat for electricity. Fervo is now drilling wells for its first 400-megawatt commercial power plant in Utah, next to the Forge site.
“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.” Enhanced geothermal faces other challenges, Dr Moore cautioned. Underground geology is complex, and it is tricky to create fractures that maintain heat and do not lose too much water over time. Drillers must avoid setting off earthquakes, a problem that plagued geothermal projects in South Korea and Switzerland. Forge closely monitors its Utah site for seismic activity and has found nothing worrisome.