Constellation Energy's venture capital arm invested in a $7 million seed round for Fluxnium, a startup looking to commercialize domestic uranium sourced from seawater.

The funding round was led by Congruent Ventures, with participation from Constellation Technology Ventures and the Canadian climate-technology fund Active Impact Investments.

Fluxnium said Monday that seawater holds around a thousand times more uranium than all known terrestrial deposits combined. It said it developed a proprietary high-surface-area fiber to passively adsorb uranium from seawater.

"Fluxnium is developing a new domestic and sustainable supply of uranium, passively adsorbed from seawater on proven offshore infrastructure--at a cost projected to compete with conventional mining, with no tailings or ground water concerns," Fluxnium Chief Executive Jeff Green said.

Constellation's vice president of nuclear fuels, Jason Murphy, said the company's technology "has the potential to broaden future fuel supply options and support growing demand for clean, reliable nuclear energy."

Fluxnium plans to use the seed funding to develop, pilot test, and scale its technology platform.