Los Angeles – September 21, 2026 -- Fluxnium, Inc. has closed a $7 million seed round led by Congruent Ventures to commercialize technology that adsorbs uranium directly from seawater, targeting a domestic alternative to mined ore for nuclear fuel supply. Constellation Technology Ventures, the venture arm of Constellation (NASDAQ: CEG), and Active Impact Investments, Canada's largest climate tech seed fund, also participated in the round.
Seawater holds roughly 1,000 times more uranium than all identified land deposits combined
Fluxnium's proprietary high-surface-area fiber, developed in partnership with a U.S. national laboratory, passively captures dissolved uranium as seawater flows through it. The fiber deploys on longline systems in open water, the same passive infrastructure used in commercial seaweed and mussel farming, then is retrieved, processed and redeployed.
The U.S. imports more than 90% of its uranium as nuclear demand accelerates
CEO and Founder Jeff Green said the company is developing a domestic, sustainable uranium source at a cost projected to compete with conventional mining, without tailings or groundwater contamination risks. Fluxnium's model expands production capacity by adding fiber rather than by financing new mine construction, bypassing the multi-year capital and regulatory timelines typical of terrestrial uranium projects.
Global nuclear power generation is projected to grow 2.5X over the next 15 years
Active Impact Investments General Partner Tom Boddez cited that projected growth in backing the round, pointing to Fluxnium co-founders Jeff Green and Jim McDermott's prior track record commercializing hardtech ventures. Constellation's Vice President of Nuclear Fuels, Jason Murphy, said the technology could broaden future fuel supply options for the clean energy sector, though Constellation's investment does not constitute a fuel-purchase commitment.
Congruent Ventures says the ocean could become one of the lowest-cost uranium sources
Congruent Ventures Partner Kevin Kopczynski said current uranium market dynamics create a new path for ocean-based supply to compete on cost. Proceeds from the seed round will fund further technology development, pilot testing and scale-up of Fluxnium's fiber platform.