The abundant but expensive energy source that’s under your feet

The abundant but expensive energy source that's under your feet

A rare political agreement on geothermal potential

The abundant but expensive energy source - Despite current political divides, there's a rare agreement on the potential of geothermal energy. This renewable resource taps into the Earth's internal heat, and new technologies are now enabling access to deeper, hotter, and more diverse geological regions than ever before. Liberals are drawn to its low greenhouse gas emissions, while conservatives value its promise for energy independence, leveraging familiar drilling methods from the oil and gas sector.

Efforts to expand geothermal capacity have gained momentum, with some U.S. states streamlining permits for such projects. In April, lawmakers from both parties proposed the Next-Generation Geothermal Research and Development Act, aiming to fund innovation in advanced systems. One such innovation is enhanced geothermal systems (EGS), which involve fracturing underground rock through hydraulic methods. This process—commonly known as fracking—has become a familiar yet contentious technique in the oil industry.

"It's the same techniques and up to a point it's the same industry as well," says Gernot Wagner, a climate economist at Columbia Business School. "From a climate perspective, there's a huge difference." He emphasizes that while EGS carries risks like seismic activity, its benefits outweigh these concerns. The technology offers a reliable, renewable energy source with large-capacity output, making it a promising path forward.

Quaise's breakthrough in drilling

Quaise, a company born from research at the Massachusetts Institute of Technology, is pioneering a novel approach to geothermal extraction. Their method uses millimetre-wave drilling, where electromagnetic waves in the microwave spectrum are directed to melt and vaporize rock. "We're essentially sending these waves to break through the crust," explains Harry Kelso, Quaise's communications manager. This innovation could unlock super-hot geothermal resources in previously inaccessible locations.

While conventional drilling is still used in Quaise's Oregon project, the company faces challenges as rock hardness and extreme temperatures push traditional tools to their limits. Replacing drill bits adds to costs and delays, but Quaise's approach eliminates this need. "We're not using a physical drill bit," Kelso notes, highlighting the technology's efficiency in high-temperature environments.

Overcoming water and economic hurdles

Water plays a critical role in geothermal systems, but new designs aim to mitigate risks of contamination or overuse. Quaise's initial setup requires significant water, yet the resource is continuously recycled through the super-hot rock formations. "We're essentially just reusing the water over and over," Kelso says, underscoring the sustainability of their process.

Though geothermal projects remain costly to launch, Quaise believes targeting temperatures between 300°C and 500°C could improve economics. "The hotter the resource, the more energy you can extract," Kelso argues. This strategy aligns with the broader goal of advancing geothermal as a viable alternative to fossil fuels, with the Oregon project targeting operational readiness by 2030.