What is ‘superhot’ geothermal? Deep rock to baseload power, explained

The next big baseload power plant may not rise on a riverbank or coastal inlet. It may sit on a four‑acre pad in the high desert, quietly punching holes six miles deep into basement rock and pulling out heat above 750°F (400°C).

As data centers and EV chargers devour megawatts (MW), a new class of geothermal developers aims to tap an energy resource blanketing every continent: superhot rock.

Conventional geothermal only generates about 16 gigawatts (GW) worldwide because developers historically hunted rare locations with hot water and open fractures. As I described at the Great Transformation event recently in Bend, Oregon, “superhot” geothermal turns up the volume.

New companies (including mine) are drilling hotter and deeper than conventional projects, into rock heated to 300–500°C, to create our own underground reservoirs. This promises firm power, compact footprints, and a talent pipeline straight from the oil patch. Engineers are finally cracking the drilling challenge that has kept most of that heat out of reach — until now.

The resource under our feet

If you picture Earth as an apple, conventional geothermal barely scratches the skin. But our planet stores an almost absurd quantity of heat. Even that thin layer holds enough heat to power civilization for tens of thousands of years. The upper 6–12 miles (10–20 kilometers) of crust contain orders of magnitude more energy than all known fossil reserves combined.

Historically, developers only tapped that resource where geology cooperated, chasing locations with a lucky overlap of steep geothermal gradients, water, and natural fractures. So geothermal grew in a few niches.

Superhot geothermal shuffles the deck: Instead of looking for where nature already created a reservoir, engineers drill down to hot rock, then build the reservoir themselves.

From shale playbook to superheated rock

The drilling crew sinks injection and production wells into deeper, hotter rock—often granite. Directional drilling and fracking techniques honed on shale create a network of fractures connecting the wells. Cold water flows down the injection well, soaks up heat, and returns up production wells as high‑enthalpy fluid ready for a power plant.

At Quaise Energy, we’re designing well pairs and triplets targeting 20–40 MW of electric output to compete with gas‑fired units on a per‑pad basis. Going superhot changes the math: at temperatures above roughly 572°F (300°C), a well can deliver up to 10 times more energy than typical geothermal producers at similar flow rates, for decades with no carbon emissions.

The drilling wall

The main obstacle lurks in the wellbore. Conventional drilling can reach depths greater than 6 miles and handle superhot formations, but rarely both at once without runaway costs.

As depth and temperature climb, drill bits encounter hard crystalline rock. Penetration rates slow, and non-productive time explodes as crews withdraw gear to replace worn bits, swap tools, and troubleshoot equipment. Each round trip burns time and money, sending costs exponentially higher.

Scaling superhot geothermal requires flattening that curve, so depth and temperature no longer combine to wreck the budget.

Millimeter-wave drilling: Fusion tech goes downhole

Here at Quaise, we tackle that challenge with millimeter‑wave drilling, which relies on energy‑matter interaction instead of mechanical crushing. It borrows from nuclear fusion, growing out of research started at MIT in 2008.

A surface gyrotron generates high‑power microwave beams in millimeter wavelengths, carried down the well via a metallic waveguide. When the beam hits rock, minerals absorb the microwaves, heating rapidly to crack, melt, or vaporize it into fine particles or ash. A gas stream travels down the waveguide, sweeping the particles to the surface.

Avoiding grinding contact minimizes downhole equipment wear. Relying on energy delivery rather than torque keeps performance stable as depth increases. In principle, millimeter‑wave drilling makes 5‑ to 10‑mile holes routine. Extracted energy repays the investment within months and powers continued drilling. From a safety standpoint, it mirrors a microwave oven heating food—just at far higher power with industrial‑grade safeguards.

A first project on the flanks of a volcano

Quaise’s first full‑scale demonstration, funded by our recent $134 million Series B, will not wait for the deepest wells.

We hold a lease on the side of the Newberry Volcano in central Oregon, where superhot conditions start at 2–3 miles. Roads, a four‑acre well pad, and initial permits are in place.

An initial confirmation well will validate temperature profiles, rock properties, and stress fields, later converting to a monitoring well. Next, we drill an injection–production pair to 575–660°F (300–350°C) using commercially available tools, followed by another production well to form a triplet.

Later phases will go deeper and hotter, adding millimeter‑wave drilling to support 250 MW from six wells on the initial pad and demonstrate competitive power production from superhot EGS.

Safety, workforce, and the road to scale

EGS operations pump water and proppant—not hydrocarbons—through wells engineered thousands of feet below aquifers.

We manage induced seismicity risks with dense sensor networks and conservative injection strategies; events at DOE’s FORGE site and Fervo projects are so small they are nearly undetectable on the surface.

Our sector welcomes the oil and gas skillset wholesale: reservoir and drilling engineers, geologists, rig crews, and technicians can pivot with modest retraining.

Our larger hurdle is getting incumbents to treat geothermal as a core business. With today’s focus on 24/7 firm power and solving permitting and grid queue challenges, superhot geothermal can become the global backbone of a decarbonized grid.