Can Undersea Volcanoes Power Cities? A Seattle Startup Just Took the First Step
Seattle-based Endurance Energy ran a full drilling-to-electricity cycle on an active underwater volcano and produced net-positive power for under 10 seconds, a first for the industry.
Operators in Seattle started, stopped and monitored the plant remotely, and the company’s next step is up to six 2-megawatt generators, each about the size of a shipping container, off Tonga.
Cost is the open question: Stanford’s Roland Horne says underwater would be pricier than land, while the DOE sees enhanced geothermal supplying 90 gigawatts in the U.S. by 2050.
A geothermal startup aiming to source energy directly from undersea volcanoes just hit a major milestone that could bring round-the-clock clean energy to cities on the northwest coast of the United States and serve as a critical proof of concept for other regions, with particular relevance for the other 14 countries situated along the Pacific Ring of Fire.
Seattle-based energy startup Endurance Energy just announced that it successfully created net-positive energy from its underwater geothermal plant in a world first. The company successfully demonstrated a full operations cycle from drilling to electricity generation in a major breakthrough for next-gen clean energy tech. Although the demonstration created less than 10 seconds of positive energy production, the implications of those ten seconds are hard to overstate.
“On Sept. 27, we put a power plant on an active underwater volcano and made power,” said Andrew Redd, founder and CEO of Endurance Energy. “This historic milestone is also our first end-to-end test. We now know, firsthand, what works at depth, what needs to be improved, and how to build the next system for sustained commercial generation.”
Not only does the brief achievement serve as a critical proof of concept for the technology, the project also “showed that operators in Seattle could control the system from an offshore location, remotely starting and stopping the equipment, monitoring temperatures and pressures, and collecting data without being underwater,” according to a recent report from Interesting Engineering.
Putting a geothermal plant on the seafloor presents some key benefits as compared to traditional models, but also yields critical trade-offs. The cool water of the seafloor acts as a natural cooling system, and the pressure of the water acts as a natural pressurizer that allows for the plants to be designed compactly, according to Redd. The company’s next milestone, building a larger 2-megawatt commercial generator in the Pacific island nation of Tonga, will be a test of these more productive, but still compact, generator systems.
“The 2 MW commercial generators will be about the size of a shipping container, and we are deploying up to six of these generators to offshore Tonga,” Redd told Ars Technica. “The physical footprint of this project will be relatively small.”
However, building a geothermal plant underwater presents extra challenges that could incur prohibitively high upfront costs as compared to on-land models. “It’s probably technically feasible, but it would undoubtedly be more expensive than to do it on land,” Roland Horne, professor of energy science & engineering at Stanford University, recently told Ars Technica.
Underwater geothermal is just one of many next-gen geothermal technologies being developed and tested today, as the urgency of shoring up new, clean, and indigenous forms of energy production becomes an ever-more urgent imperative against the backdrop of the artificial intelligence boom. Big Tech companies are bullish about investing in enhanced geothermal energy as part of their clean energy portfolios, while the Trump administration has also thrown its weight behind the sector’s development.
Indeed, one of the biggest benefits of geothermal energy is that it is one of the vanishingly few clean energy technologies that enjoy broad bipartisan support. By borrowing drilling techniques from the oil and gas industry, the United States could position itself as a global leader in advanced geothermal energy in coming years, a goal which aligns itself with the decarbonization priorities of the left and the energy dominance aims of the right.
“The U.S. has a number of different superpowers, and putting holes in the ground and taking things out of those holes is one of them — and doing so more economically and more efficiently than basically any other place on Earth,” Drew Nelson, vice president of Project InnerSpace, was quoted by Cipher News.
Accordingly, the Department of Energy has high hopes for the emerging technology, estimating that enhanced geothermal projects could provide an impressive 90 gigawatts of clean energy in the United States by 2050, or about enough to power at least 65 million homes.




