Quaise Energy, a startup born out of MIT’s Plasma Science and Fusion Center, is making waves in the geothermal energy sector with its innovative drilling technology. On May 21, 2025, the company demonstrated its millimeter wave drilling technology at the Nabors facility in Houston, Texas, marking a significant step toward unlocking vast, untapped geothermal resources. The goal? To dig the world’s deepest hole and tap into the Earth’s “superhot” rock, making geothermal power accessible virtually anywhere.
The Promise of Deep Geothermal Energy
Geothermal energy, harnessing heat from within the Earth, offers a clean, constant, and reliable power source. Unlike solar and wind, geothermal energy operates 24/7, unaffected by weather conditions. However, traditional geothermal plants are limited to specific locations with naturally occurring hot reservoirs near the surface. Quaise Energy seeks to overcome this limitation by drilling deeper than ever before, accessing the Earth’s abundant “superhot” rock, which exists everywhere.
According to Paul Woskov, a senior fusion research engineer at MIT, tapping into just 0.1% of the Earth’s heat could supply the world’s energy needs for over 20 million years. The challenge lies in reaching these extreme depths efficiently and economically.
How Quaise Energy’s Technology Works
Quaise Energy’s approach combines conventional drilling with millimeter wave technology, adapted from nuclear fusion research. Here’s a breakdown:
- Conventional Drilling: Traditional rigs bore through the first 2-3 kilometers (approximately 2 miles) until they hit basement rock.
- Millimeter Wave Drilling: Once basement rock is reached, Quaise swaps the drill bit for its millimeter-wave drill. This system utilizes a gyrotron, a device that generates high-frequency millimeter waves, to vaporize the rock.
- Vaporization Process: The millimeter wave beam, like a high-powered microwave, heats the rock to the point of melting or vaporization, creating a crater-like hole.
- Waste Removal: Nitrogen gas is pumped into the hole to flush out the dust and vaporized rock particles as the drill moves deeper.
Quaise’s technology aims to drill depths exceeding 12 miles (20 kilometers), where temperatures can reach nearly 1,000°F (500°C). At these depths, water becomes supercritical, possessing ten times more energy transfer capacity than at lower temperatures. This supercritical water can then be used to power turbines, generating electricity far more efficiently than conventional geothermal systems.
A Demonstration of Groundbreaking Tech
During the May 2025 demonstration, Quaise used a 100-kW gyrotron powered by 50,000 volts DC, connected to a Nabors F rig with a custom top drive. The drill, operating at roughly 48 kW, melted a hole into a granite/basalt rock mix at a rate of approximately 0.8 inches (2 cm) per minute. This demonstration showcased the technology’s ability to precisely focus the millimeter wave as the drill moves deeper, a significant hurdle in its development.
Overcoming Challenges and Future Plans
Quaise Energy’s journey has involved overcoming several engineering challenges. Key among these was maintaining the millimeter wave’s focus as the drill descends. The company’s “articulated wave guide” has proven capable of achieving a consistent borehole shape, at least over short distances.
Looking ahead, Quaise has ambitious plans:
- Near-Term Testing: Next month, Quaise will utilize a 1 MW gyrotron for further testing. They also have a test site in Marble Falls, Texas, with rigs capable of digging nearly 500 feet (150 meters).
- First Commercial Plant: Quaise aims to have a 50-MW geothermal plant operational near Bend, Oregon, within three years. This will start with a 20-MW system using conventional drilling, followed by an additional 30 MW using their millimeter wave technology.
- Repowering Fossil Fuel Plants: Quaise envisions retrofitting existing fossil-fueled power plants with their geothermal system, leveraging existing infrastructure and accelerating the transition to clean energy. They aim to repower their first fossil-fired power plant with clean geothermal steam by 2028.
The Kola Superdeep Borehole Inspiration
Quaise’s ambition to drill the world’s deepest hole draws inspiration from the Kola Superdeep Borehole, a project undertaken by the Soviet Union in the 1970s. The Soviets aimed to drill 7.62 miles (12.26 km) into the Earth’s crust, but they were forced to abandon the project due to unexpectedly high temperatures (180°C/356°F) and equipment meltdowns.
Quaise plans to surpass this depth, reaching over 12 miles (20 km) and temperatures of nearly 1,000°F (500°C). Unlike the Kola project, which took nearly 20 years, Quaise estimates its gyrotron-enhanced process will take just 100 days, assuming a 1-MW gyrotron.
Financial Backing and Partnerships
To date, Quaise Energy has raised $105 million in funding and seeks to raise an additional $200 million to develop its first commercial power plant. The company has secured multiple geothermal leases and is managing the power plant development process in-house.
Quaise is also collaborating with the existing drilling industry, adopting a “BYOG” (Bring Your Own Gyrotron) approach. This involves integrating their millimeter wave drilling technology with conventional drilling rigs, allowing them to leverage the existing global drilling infrastructure.
Benefits of Quaise’s Approach
Quaise Energy’s technology offers several potential benefits:
- Access to Universal Geothermal Energy: By drilling deep enough to reach “superhot” rock, geothermal energy can become accessible virtually anywhere on Earth.
- Higher Power Density: Supercritical water at extreme depths enables higher power density, making geothermal energy competitive with fossil fuels.
- Repowering Existing Infrastructure: Retrofitting existing fossil-fueled power plants with geothermal systems accelerates the transition to clean energy and reduces reliance on fossil fuels.
- Constant and Reliable Energy: Geothermal energy provides a constant, 24/7 power supply, unlike intermittent sources like solar and wind.
- Small Land Footprint: Geothermal plants have a smaller land footprint compared to wind and solar farms for the same maximum output.
- No Fracking Required: Quaise’s drilling method does not require fracking, eliminating the potential for earthquakes associated with other geothermal systems.
Challenges and Considerations
Despite the potential benefits, Quaise Energy faces several challenges:
- Technological Hurdles: Scaling up the millimeter wave drilling technology to commercial levels requires further engineering advancements and testing.
- Cost Competitiveness: The cost of drilling ultra-deep boreholes needs to be competitive with other energy sources.
- Regulatory Approvals: Securing permits and navigating regulatory hurdles for geothermal power plants can be a complex and time-consuming process.
- Material Science: Ensuring the durability and stability of materials used in ultra-deep boreholes under extreme temperatures and pressures is crucial.
The Future of Geothermal Energy
Quaise Energy’s innovative drilling technology holds immense potential to revolutionize the geothermal energy sector. By unlocking access to the Earth’s vast reserves of “superhot” rock, geothermal energy can become a major player in the global transition to clean energy. While challenges remain, Quaise’s progress and ambitious plans offer a promising glimpse into a future powered by the Earth’s boundless heat.
