As the United States aims to triple its nuclear energy capacity by 2050, rising costs and limited domestic uranium reserves have emerged as significant obstacles. Prices for yellowcake, the unrefined form of uranium, have climbed 75% over the past five years, according to the U.S. Energy Information Administration. However, a clean-tech startup named Fluxnium believes it has identified a solution within the oceans, which contain an estimated 4 billion metric tons of uranium—enough to fuel the world for approximately 50,000 years.
“It’s like a thousand times more than all identified hard rock mines combined,” Jeff Green, the founder and CEO of Fluxnium, told TechCrunch. The company recently provided an exclusive look at its technology after operating in stealth mode, revealing a process derived from U.S. Department of Energy national labs that could compete with traditional mining on cost.
Fluxnium has closed a $7 million seed funding round led by Congruent Ventures, with additional participation from Active Impact Investments and Constellation Energy, the operator of the largest nuclear fleet in the U.S. This investment arrives as the domestic nuclear sector experiences a resurgence, driven largely by technology companies seeking reliable power sources for AI data centers.
Green, a serial entrepreneur who previously co-founded Stamps.com, NanoH2O, and 1PointFive, argues that uranium supply chains are vulnerable to geopolitical instability. He noted that two-thirds to three-quarters of global uranium originates from countries such as Kazakhstan, Uzbekistan, Russia, Namibia, Niger, and China. “If demand comes the way it’s being projected, we’re structurally short uranium,” Green said.
The Fluxnium method utilizes specialized polymer fibers licensed from the DOE to attract dissolved uranium from seawater. While initial demonstrations at national labs yielded uranium at a cost exceeding $200 per pound—more than double the current market price—Green stated that increasing the surface area of the fibers has significantly reduced production expenses.
The operational process resembles seaweed farming: long, braided fibers are deployed from buoys and left in the ocean for 30 to 60 days. Upon retrieval, the uranium is extracted without generating toxic tailings, and the fibers can be reused multiple times. The collected uranium is then purified into yellowcake and sold into the existing supply chain. Green emphasized that while no single component of the process is novel, the company’s focus is on optimizing the supply chain to drive costs down to competitive levels.
Wait, so we’re turning the entire ocean into a mine? Remind me why we didn’t just think to do this decades ago?
No toxic tailings? If they can make this work at scale, it’s a game-changer for green nuclear energy compared to traditional mining.
Constellation Energy investing makes sense. AI data centers need that reliable baseload power, and this could solve their uranium shortage.
I’m skeptical about scaling this. The ocean is harsh on equipment. Can they really farm uranium without massive maintenance costs?
This is huge for energy independence. We stop relying on Kazakhstan and Russia for our nuclear supply? Count me in.
Fifty thousand years of fuel sounds incredible, but I wonder if they can actually get the cost down from $200 a pound to compete with mining.