Endurance Energy secures $54 million to develop ocean‑floor

Endurance Energy, a startup founded by former SpaceX engineer Andrew Redd, announced a $54 million Series A round to develop geothermal power plants on the ocean floor [1]. The funding, led by Founders Fund with participation from several venture firms, will support the company’s plan to harvest terawatts of heat from tectonic zones around the Pacific Ring of Fire [1].

Key takeaways

• Endurance Energy raised $54 million in a Series A led by Founders Fund [2]
• The team includes 25 staff, half of whom previously worked at SpaceX [1]
• The startup aims to capture deep‑sea geothermal energy to provide 24/7 baseload power [1]
• Target markets include AI data centers, electric‑vehicle charging and heavy industry [1]
• Redd estimates up to 6 TW of ocean‑floor geothermal potential near the Ring of Fire [1]

From rockets to the deep sea: founding vision

Andrew Redd, who engineered SpaceX’s Dragon and Starship vehicles, left the aerospace firm to pursue a renewable‑energy solution he describes as “brand new” and grounded in first‑principles thinking [1]. Drawing on his Pacific‑Northwest upbringing and concerns about heat waves and wildfires, Redd founded Endurance Energy last year with the goal of tapping the Earth’s heat beneath the ocean. The company’s vice‑president of engineering previously worked at fusion startup Helion Energy, adding further deep‑tech expertise to the team [1].

Building a submarine‑based geothermal platform

Endurance plans to install power‑generation modules on the seafloor where tectonic plates diverge, allowing magma‑heated water to rise naturally. The approach relies on robotic drilling and corrosion‑resistant hardware, leveraging decades of offshore oil‑and‑gas experience [1]. By locating sites a few dozen to several hundred miles off coastlines, the firm will balance the cost of submarine cables against resource size, while avoiding ecologically sensitive hydrothermal vents [1]. Redd argues that even a modest fraction of the estimated 6 TW of accessible heat could supply continuous electricity to major coastal cities along the Ring of Fire [1].

Why it matters

If successful, Endurance’s ocean‑floor geothermal plants could provide a truly baseload, low‑carbon energy source that sidesteps the intermittency of solar and wind and the regulatory delays of nuclear power [1]. The $54 million capital infusion equips the startup to advance prototype development and begin field trials, positioning it among a growing cohort of geothermal innovators such as Fervo and Zanskar [1]. Continued progress will depend on technical validation of deep‑sea drilling, cost‑effective power transmission, and regulatory approval for offshore installations.