Zeno Power, a Seattle-based developer of nuclear batteries for extreme environments, has closed a $50 million Series B funding round to accelerate manufacturing capabilities and meet growing demand from government and commercial customers. The round was led by Hanaco Ventures with participation from space and defense-focused investors including Seraphim, Balerion Space Ventures, JAWS, Vanderbilt University, RiverPark Ventures, Stage 1 Ventures, 7i Capital, and Beyond Earth Ventures.
The funding will enable Zeno to expand its team from 65 employees to more than 100 across its Seattle headquarters and Washington, DC operations, while investing in manufacturing infrastructure to scale production of its radioisotope power systems ahead of planned first deliveries in 2027.
Government Contracts Drive Commercial Momentum
Founded in 2018, Zeno has established significant traction in the government sector, securing over $60 million in contracts from NASA and the U.S. Department of Defense to develop nuclear batteries for demanding applications. These include power systems for highly maneuverable satellites, lunar landers, and critical seabed infrastructure where traditional power sources prove inadequate.
The company's nuclear batteries, also known as radioisotope power systems, convert heat generated from radioactive decay into electricity. This technology offers substantially longer operational lifespans compared to conventional power systems, making them particularly valuable for missions in space, polar regions, and deep ocean environments where maintenance and replacement are impractical or impossible.
"The deep ocean, Arctic, and space are emerging as key contested domains for global influence," said Tyler Bornstein, Zeno's co-founder and CEO, in a blog post announcing the funding. "These regions are already vital for global commerce and government operations, and great power competition is turning them into strategic arenas where nations and companies vie for presence, resources, and control. But one challenge persists: energy."
Technical Milestones and Manufacturing Scale-Up
Zeno has made significant technical progress in the three years leading up to this Series B round. The company successfully built and demonstrated its first prototype at Pacific Northwest National Laboratory and received an initial supply of Sr-90 recycled nuclear waste from the Department of Energy, providing the radioactive material necessary for its power systems.
NASA has historically relied on similar radioisotope power systems for deep space missions, where solar panels become ineffective due to distance from the sun and extreme environmental conditions. Zeno's technology builds on this proven approach while targeting expanded applications in terrestrial extreme environments.
The company aims to complete full-scale demonstrations of its nuclear batteries by the end of 2026, with commercial deliveries beginning in 2027. This timeline aligns with growing demand from both government and commercial customers operating in frontier environments where reliable, long-duration power remains a critical challenge.
Strategic Leadership and Market Position
In conjunction with the Series B funding, former Chief of Naval Operations John Richardson joined Zeno's board of directors. Richardson's extensive naval career includes service as director of the Naval Propulsion Program, bringing deep expertise in nuclear power systems and defense applications to the company's strategic guidance.
This latest funding round brings Zeno's total capital raised to over $70 million, following a $20 million Series A round led by Tribe Capital in 2022. The company's ability to attract significant investment reflects growing recognition of nuclear batteries as a critical enabling technology for operations in contested and extreme environments.
The nuclear battery market represents a specialized but strategically important segment of the broader energy storage industry. As geopolitical competition intensifies in space, Arctic regions, and deep ocean environments, reliable power systems become essential infrastructure for maintaining operational capabilities in these domains.
Zeno's focus on recycled nuclear waste as fuel source also addresses sustainability concerns while providing a practical application for existing radioactive materials. The Sr-90 supply from the Department of Energy demonstrates government support for developing domestic nuclear battery capabilities using existing waste streams.
