Science & Tech · Science & Environment · 1 hr ago
Endurance Energy’s Undersea Geothermal Test Produced Net Power for 8.7 Seconds
Endurance Energy tested undersea geothermal power at an underwater volcano about 300 miles off Oregon’s coast.
The Seattle-based startup drilled a well about 52 feet deep and two inches wide on the seafloor, roughly a mile below the surface.
Water from the well was too restricted to provide enough heat, so the team connected its generator to a naturally flowing vent instead.
The generator produced more power than it used for 8.7 seconds, before a failed power cable stopped the test.
The company sees the trial as an early step toward undersea power plants supplying steady clean energy.
The test showed the system could be deployed and operated underwater, but the company’s longer-term vision will require overcoming the challenges of building and maintaining equipment in the ocean.
Endurance Energy tested a subsea geothermal power system at Axial Seamount, an underwater volcano about 300 miles off Oregon.
The team drilled a well about 52 feet deep and two inches wide, short of its 200-foot target.
After connecting its generator to a natural hydrothermal vent, the team produced about 2 kilowatts of net power for 8.7 seconds.
A software glitch and a failed power cable stopped the test.
The Seattle-based startup says the trial supports its vision of a network of undersea power plants supplying baseload clean energy.
- Who
- Endurance Energy, a Seattle-based startup led by founder and CEO Andrew Redd.
- What
- The company tested a subsea geothermal well and generator. The generator produced about 2 kilowatts of net power for 8.7 seconds.
- When
- September 2026, according to Fast Company; Heatmap says the test took place last month.
- Where
- At Axial Seamount, about 300 miles off the Oregon coast and roughly a mile underwater.
- Why
- To test generating electricity from undersea geothermal heat as a step toward a network of undersea power plants.
This story does not have two clearly opposing sides.
Endurance Energy launched.
The company raised a $54 million Series A, according to Heatmap.
The team tested its geothermal system at Axial Seamount, drilling a 52-foot well and running the generator.
A software glitch shut down the plant, and a failed power cable prevented the team from restarting it.
- Test site
- Axial Seamount, about 300 miles off Oregon
- Water depth
- About 5,000 feet, or roughly one mile
- Well
- About 2 inches wide and 52 feet deep
- Net power
- About 2 kilowatts for 8.7 seconds
- Funding
- $63 million raised to date, according to Fast Company
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What people are saying
We really proved with this mission that a geothermal well could be drilled and completed on the seafloor, and doing that within 21 months of the company existing I think is really a testament to our pace of progress
No one’s ever tried this even close to the commercial scale that we’re going after
We follow the adage ‘make it exist, then make it good.’
I wanted to go after something that was going to be both really good for the world but also extremely compelling from an employee perspective
Posts on X
This is an old lawsuit brought by the local community—who had serious concerns about this project—against the Biden Administration! The White House maintains support for PERMITTING REFORM! We look forward to the Senate voting on this historic legislation. The media should stop