In 2009, on a plot of shrub-covered cattle land about 45 miles northwest of McAllen, Shell buried and abandoned a well it drilled to look for gas. The well turned out to be a dry hole. Vegetation grew back over the site.
In 2021, a Houston-based energy company run by former Shell employees came looking for it.
This company wasn’t drilling for oil or gas, though. Its engineers were looking for a place to experiment with their technology for producing geothermal energy, created by Earth’s underground heat.
A startup called Sage Geosystems leased the site. The company installed a wellhead and brought in a diesel-powered pump. They used fluid to create cracks in the rock deep below the surface, a technique similar to fracking for oil and gas.
One day last March, the crew pumped 20,000 barrels of water into the 2-mile-deep well. Hours later, an operator opened the well from a control room. Pipes above ground shook as the pressurized water gushed back up. The water spun small turbines, generating electricity.
Sage and other companies believe geothermal power is key to replacing polluting coal- and gas-fired power plants. Even though solar and wind are proven clean energy sources, they only produce electricity when the sun shines or the wind blows. Geothermal power could provide continuous, emissions-free energy.
“Geothermal heat doesn’t have those variable conditions,” University of Texas at Austin clean energy expert Michael Webber said. “If you hit a hot spot below ground—might be thousands of feet down—the heat won’t matter based on whether it’s cloudy or whether it’s summer.”
Texas has become an early hot spot for geothermal energy exploration. At least three companies are based in Houston, and scores of former oil industry workers and executives are taking their knowledge of geology, drilling and extraction to a new energy source.
“We’ve punched over a million holes in the ground in Texas since Spindletop,” said former Texas oil and gas regulator Barry Smitherman, who has become a geothermal advocate. “So we have a lot of knowledge, and we have a lot of history and skill set.”