Back in the seventies and eighty’s the United States was the dominant force in uranium enrichment, but over the last three decades, we have allowed that leadership role to wither as other countries developed their own centrifuge enrichment technologies. The US went from the world’s largest exporter of nuclear fuel to the world’s largest importer, dependent on imports from Russia and Europe to fuel our existing fleet of reactors.
The vast majority of the world’s fleet of existing nuclear reactors are light water reactors. Their fuel is enriched 3-5% U-235, classified as low-enriched uranium. However, most of the next generation nuclear reactors are designed to run on enrichments of 5-20% U-235, classified as HALEU (high-assay low-enriched uranium). This higher energy density fuel allows smaller reactor designs, longer-lasting cores, and less waste, according to the Department of Energy.
The process of increasing the higher concentrations of U-235 is accomplished in a centrifuge, which takes advantage of the slight difference in weight between the naturally occurring uranium isotope and the 235 isotopes.
Recently, a company based out of Piketon, Ohio, Centrus Energy, cleared an operational readiness review by the Nuclear Regulatory Commission, which means that they can manage the materials needed to produce HALEU. That makes Centrus Energy the only facility in the US licensed to produce HALEU. They plan to start production by the end of this year, using sixteen newly constructed centrifuges, the product of a three-year demonstration project with the DOE to build their enrichment cascade. Although Centrus cleared one significant hurdle with this approval, the road ahead is uncertain, as they still need to wade through regulatory and economic challenges before, they can begin commercial production of HALEU.
There are several next-generation plants scheduled for operation in 2028. In fact, nine or the ten reactors selected for the DOE’s Advanced Reactor Demo Program will require HALEU fuel. The DOE predicts that more than 40,000 kilograms will be needed before 2030.
Centrus Energy expects their demonstration project to only deliver twenty kilograms of HALEU before the end of the year but have plans to provide nine hundred kilograms per year starting in 2024. It would take 120 centrifuges to produce 6.000 kilograms per year of HALEU fuel.
According to Patrick White of the Nuclear Innovation Alliance. “If we want a reactor online by 2027 or 2028, we need to start producing the fuel in 2025 or 2026, which means that we are now down to three to four years to bring this capacity online. We need to work more quickly to bring up a domestic infrastructure that we can rely on and break this chicken-and-egg problem with demand.”
The DOE has indicated it will attempt to serve as an anchor customer for HALEU fuel by being the first buyer, which should help capital investments flow in from private industry. There is an earlier historical parallel for this approach: Last century, the U.S. government, built enrichment plants for national-security purposes. In 1956, then-President Eisenhower made $1 billion ($11billion in today’s dollars) worth of enriched uranium available to utilities in the United States and around the world in exchange for meeting nonproliferation standards. The program was a major success, enabling the commercial nuclear plants to be built in the sixties, seventies, and eighties. Today, seven decades later, this approach might just be what is needed to get things moving with building our next generation nuclear plants.