Can Heat from the Earth Power the Future?

Trane and GreenFire adapt sealed-pipe technology to cut seismic risk and expand geothermal in new markets

16 Mar 2025

In the race to reinvent energy, one of the most promising breakthroughs isn’t happening in the skies with wind turbines or on rooftops with solar panels. It’s happening underground.

Across schoolyards in Illinois and aging steam fields in California, a low-profile technology is gaining ground: closed loop geothermal systems. By quietly tapping the Earth’s natural heat, they’re offering a clean, steady power source without the headaches of traditional drilling or the drama of fossil fuels.

Unlike older geothermal systems, which involve injecting water deep underground and risking seismic activity, closed loop setups use sealed pipes to circulate fluid through the Earth’s subsurface. The result? Far fewer permits, minimal environmental impact, and an entirely new map of where geothermal can work.

Take North Shore School District 112 in Illinois, where Trane Technologies recently installed a closed loop system that now delivers year-round heating and cooling without touching fossil fuels. Out West, GreenFire Energy is breathing life back into The Geysers, once the heart of U.S. geothermal power, by converting abandoned wells into low-impact energy sources.

“This approach removes two major roadblocks: earthquake risks and permitting delays,” said Dr. Casey Elwell of the National Renewable Energy Laboratory. “It’s expanding geothermal’s reach dramatically.”

With growing pressure to find clean, reliable energy, the appeal is obvious. Closed loop geothermal runs around the clock and isn’t hostage to sunshine or wind. It’s especially useful for big energy users like hospitals, universities, and data centers.

Federal incentives are speeding things up too. Tax credits from the Inflation Reduction Act are lowering costs and spurring new projects across the country.

There are still questions about long-term performance and scalability. But the momentum is real and growing fast.

If this quiet trend continues, closed loop geothermal could become one of the most transformative energy technologies in decades. No smoke, no noise, just heat from the Earth, turned into power for a changing world.