Nuclear power of the future is going to need fuel. That has governments, energy companies and nuclear engineers clamoring to get their hands on HALEU: high-assay low-enriched uranium.

HALEU (pronounced like “Hey, Lou”) was previously a niche material, used mainly in nuclear reactors conducting scientific research. But now, multiple companies in the United States have proposed newfangled types of nuclear reactors that they claim will generate electric power more efficiently and safely. Such reactors, many of which will run on HALEU, are a key part of the United States government’s plan to meet future demands for clean energy (SN: 12/14/22).

On June 10, TerraPower, a company founded by Bill Gates, broke ground on what is to be one of the first of this new generation of HALEU-fueled reactors. But currently, the United States doesn’t make that fuel in the amounts that will be needed by that cohort. So while the U.S. Department of Energy is funding the development of such advanced reactors, it is also working to secure an ample supply of HALEU fuel.