Geothermal energy has always been framed as the clean energy solution that should work. It offers firm, 24/7 baseload power, tiny land footprints, and zero carbon emissions. In theory, it complements intermittent renewables perfectly. In practice, geothermal has had a rough, stop-and-start history defined by high costs, technical risk, and limited geographic opportunity.
For decades, geothermal deployment was constrained to rare hydrothermal sites where heat, permeability, and fluid happened to align. Outside of places like The Geysers, Iceland, or parts of Indonesia, geothermal struggled to compete. Investors learned—often the hard way—that drilling risk, long development timelines, and uncertain subsurface performance could derail even well-designed projects.
Despite renewed enthusiasm, those fundamental challenges haven’t disappeared. What has changed is the scale of innovation being applied—and the willingness of patient capital, including firms like Baseload Capital, to test whether geothermal can finally move beyond its narrow historical footprint.
I recently connected with the Baseload Capital team at a 9zero discussion focused on generation and geothermal. The conversation was optimistic—but notably pragmatic. Everyone in the room understood that geothermal’s promise is real, but so are the obstacles.
Capital Cost and the Persistent Problem of Risk
Geothermal’s central problem remains front-loaded capital risk. Unlike solar, wind, or batteries—where performance can be modeled with increasing confidence—geothermal depends on subsurface conditions that are never fully known until wells are drilled. Exploration wells can cost tens of millions of dollars, and a disappointing result can materially impair an entire project.
This creates a financing mismatch. Even though geothermal assets can operate for decades with low operating costs, lenders and investors must underwrite risk before revenue exists. The result has been higher cost of capital, conservative deal structures, and a limited pool of experienced developers.
While new sensing, modeling, and data tools are improving visibility, geothermal is still far less “plug-and-play” than other clean energy assets. Reducing risk perception may take years of repeatable success, not just promising pilots.
Enhanced Geothermal Systems: Transferable Skills, Unproven Scale
Enhanced Geothermal Systems (EGS) are often cited as the key to unlocking geothermal everywhere—but that claim deserves scrutiny.
EGS borrows heavily from oil and gas techniques such as long horizontal drilling, hydraulic stimulation, and advanced drill bits. Developers like Fervo Energy have demonstrated impressive technical progress, particularly with real-time fiber-optic monitoring and controlled fracture creation. Research sites like Utah FORGE are advancing the science.
Still, major questions remain:
- Can engineered reservoirs maintain performance over decades?
- Will induced seismicity limit deployment in populated regions?
- Can costs reliably fall fast enough to compete with mature renewables?
EGS may work—but it has not yet proven it can scale economically and socially across diverse geographies.
Closed-Loop Systems: Elegant, but Capital Intensive
Closed-loop geothermal systems aim to sidestep subsurface uncertainty by sealing fluids inside wellbores. Eavor’s Eavor-Loop design is conceptually elegant, avoiding both hydraulic stimulation and groundwater interaction.
However, elegance doesn’t automatically translate to economics. Closed-loop systems require extensive drilling—often more footage than conventional geothermal—to compensate for lower heat transfer efficiency. That means high upfront capital, long construction timelines, and ongoing questions about cost competitiveness at scale.
Similarly, CO₂-based geothermal concepts, explored by firms like Siemens Energy, are promising but remain largely experimental, with unresolved regulatory and operational complexity.
Superhot Rock: Immense Potential, Extreme Difficulty
Superhot Rock (SHR) geothermal may represent geothermal’s biggest upside—and its biggest technical gamble. Accessing temperatures above 400°C could yield dramatically higher energy output per well and transform geothermal economics.
But drilling at those depths and temperatures pushes equipment beyond known limits. Even optimistic projections acknowledge that SHR depends on breakthroughs in drilling, materials, and system design that are not yet commercial.
Advanced concepts like microwave drilling, pursued by Quaise Energy, could be transformative—but they remain unproven outside controlled environments. The timeline from lab success to bankable infrastructure is uncertain and likely long.
Materials, Sensors, and the Hidden Bottlenecks
Extreme geothermal environments destroy conventional equipment. Sensors fail, coatings degrade, and maintenance becomes costly. Companies like Hephae Energy and SensorEra are addressing these gaps—but materials innovation rarely moves quickly.
Without durable, affordable components, even technically successful wells can become operational liabilities.
California: Progress, Pilots, and Pressure to Deliver
California is positioning itself as a testbed for next-generation geothermal—but pilots are not the same as scaled deployment.
Sonoma Clean Power’s GeoZone initiative aims to bring up to 600 MW of advanced geothermal online, working with partners including Chevron New Energies, Cyrq Energy, and Eavor. It is ambitious—and still early.
Other efforts, such as XGS Energy at Coso and GreenFire Energy at The Geysers, focus on improving or extending existing assets rather than creating entirely new geothermal provinces.
Meanwhile, institutions like Berkeley Lab and the California Energy Commission are funding research and pilots—but public support alone cannot guarantee commercial success.
A Necessary but Uncertain Path
The U.S. Department of Energy’s EarthShot goal—to cut geothermal costs by 90% by 2035—is bold. Whether it’s realistic remains an open question.
Geothermal likely must succeed at some level to support a deeply decarbonized grid. But success will not come easily, quickly, or cheaply. It will require years of iteration, failures, regulatory learning, and capital that understands infrastructure timelines—not venture hype cycles.
That realism was clear at the 9zero discussion. Geothermal is not a silver bullet. It is a long, difficult bet—one that may still prove essential, but only if innovation, policy, and capital remain aligned long enough to get it right.