In the race to secure truly sustainable power, a bold vision is taking shape below our feet. A MIT-born startup, Quaise Energy, is advancing a method to unlock the Earth’s heat at depths where rock turns into a vast thermal battery. By pushing beyond conventional limits, this approach could make geothermal a near-inexhaustible resource, reshaping how societies generate clean electricity.
A leap in geothermal extraction
Instead of grinding through rock, Quaise proposes to use high-power microwaves to vaporize it, creating ultra-deep, super-hot wells. The technique targets rock at around 375 degrees Celsius, where heat becomes far more concentrated and accessible. Traditional systems usually operate under 200 degrees Celsius, limiting both efficiency and scale.
The hotter the rock, the more energy can be harvested from circulating water, and the less surface infrastructure a project needs. By reaching these conditions, a single site could yield multiples of the output of current geothermal plants while keeping land use and visual impact remarkably low.
The immense underground potential
A landmark 2006 study from MIT estimated that tapping just 2% of the accessible geothermal energy between roughly 3 and 10 kilometers down could cover more than 2,000 times the United States’ annual consumption. That figure reframes geothermal from niche to transformational. At those depths, water can become supercritical—neither liquid nor gas—carrying three to four times more energy per unit mass than ordinary hot water.
Supercritical conditions enable compact wells to move enormous heat flux, improving the economics of geothermal in regions beyond classic volcanic hotspots. The result is a broader, more equitable map of opportunity for cities and industries seeking firm, clean power.
Engineering the impossible
Drilling at extreme temperature and pressure is notoriously harsh on equipment, with bits eroding and casings failing. Microwave drilling aims to sidestep mechanical wear by coupling electromagnetic energy directly into the rock, breaking molecular bonds and turning material into a removable vapor.
Because the process is largely independent of rock type and depth, it could shorten project timelines and reduce the unpredictability that plagues deep wells. Still, it requires robust systems for bore stability, materials that handle heat, and reliable removal of vitrified or condensed debris.
Water at the edge of physics
Operating with supercritical water introduces complex fluid behavior that conventional geothermal has rarely encountered. Quaise is modeling how water will expand, dissolve minerals, and transfer heat under those conditions, ensuring loop stability and safety. Understanding corrosion, scaling, and flow control in real time is essential to keep performance steady.
These models guide well design, surface equipment choices, and contingency planning, helping developers predict how the reservoir will evolve across decades of operation.
Rethinking fractures underground
Instead of relying on large, brittle fractures, Quaise aims to create a dispersed “cloud of permeability” using microfractures that connect injection and production wells. This method seeks to reduce seismic risk and improve flow uniformity, boosting system reliability over the long term.
As one leader put it, “We’re engineering a network of micro-pathways that lets heat move efficiently without the downsides of big, unstable cracks.” A testing ground at Oregon’s Newberry Volcano offers similar temperatures at shallower depths, making it an ideal place to validate the approach.
A hybrid future for geothermal
The optimal reservoir may blend natural, planar, and microfracture systems, leveraging the strengths of each. In some settings, naturally fractured zones will carry most of the flow; in others, engineered microfractures will create a more controllable, stable network. This hybrid playbook aims to maximize heat extraction while minimizing environmental trade-offs.
Such flexibility is crucial for scaling geothermal in varied geologies, ensuring projects thrive from sedimentary basins to ancient, crystalline crust.
What success would change
If microwave-enabled, super-hot geothermal matures, it could deliver firm, zero-carbon power at scale, complementing variable wind and solar. The benefits extend across the energy system and into broader economic planning:
- Reliable, 24/7 clean electricity with minimal land footprint
- Deep resource maps that reach beyond classic volcanic zones
- Potential repowering of existing energy sites and grids
- Reduced reliance on fossil baseload and imported fuels
- Local job creation in drilling, materials, and advanced manufacturing
The outcome is a more resilient grid with fewer seasonal bottlenecks and better integration of high-renewable penetration.
The path ahead
Scaling this vision will demand sustained R&D, rigorous field trials, and partnerships that align utilities, regulators, and local communities. Technical breakthroughs must be matched by clear safety frameworks, transparent monitoring, and open data that build public trust in deep geothermal projects.
Yet the prize is formidable: a stable source of clean heat and power under nearly every country’s soil. With microwave drilling, supercritical fluids, and smart reservoir design converging, geothermal may shift from underdog to cornerstone—quietly delivering the dependable, carbon-free energy a modern economy requires.
