Seattle-based company Endurance Energy has successfully generated net-positive electricity using heat from an underwater volcano. The experiment, dubbed "Adélie," took place on September 27 at the Axial Seamount, an active volcano located approximately 480 kilometers off the coast of Oregon.
Harnessing Seafloor Heat
Positioned 1,500 meters below the ocean surface, the team utilized the extreme heat of hydrothermal vents—where seawater is heated by molten rock—to drive a turbine. While previous attempts to harvest energy from seafloor vents have been limited to powering small devices like data loggers, the Adélie system achieved a significant breakthrough. During an 8.7-second interval, the generator produced a median surplus of 2 kilowatts of electricity, with a peak output of 16.5 kilowatts, after accounting for the power required to run the system's own pumps and components.
The test relied on the Regional Cabled Array, an existing undersea network operated by the University of Washington, to transmit data and control the equipment from shore. The run concluded when a safety system triggered a shutdown, followed by a subsequent cable failure during a restart attempt.
Future Outlook and Environmental Considerations
Endurance Energy is already looking toward commercial applications, with a project currently in development for Tonga that aims to provide an alternative to the nation's reliance on imported diesel. CEO Andrew Redd noted that the company’s next iteration, a 100kW generator named "Gentoo," is scheduled for deployment this winter to address the technical hurdles encountered during the initial test.
While the company reported no immediate impact on the local ecosystem—which relies on microbes and specialized marine life—they acknowledge that long-term, large-scale operations require further study. Endurance is currently collaborating with independent researchers to assess potential environmental effects on the seafloor habitat. The company’s results have been released via a press statement and are not yet subject to peer-reviewed publication.
