The US Energy Department has received the first commercial shipment of advanced nuclear fuel, which will be needed as the power industry seeks to develop new types of reactors.

Centrus Energy Corp. delivered more than 20 kilograms (44 pounds) of so-called HALEU fuel to the department, the Bethesda, Maryland-based company said Tuesday. The company began production last month at its facility in Piketon, Ohio, and expects the site to supply as much as 900 kilograms a year eventually.

Most companies developing advanced reactor designs plan to use HALEU fuel — short for high-assay, low-enriched uranium — which has a concentration of as much as 20% of the uranium-235 isotope that’s needed to sustain a fission chain reaction. That compares with about 5% for the fuel used in conventional power plants today. Raw ore contains less than 0.7% of the isotope.

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Centrus is the only US supplier of HALEU fuel, which Chief Executive Officer Dan Poneman said “is urgently needed to support the demonstration and commercialization of advanced reactors.”

Centrus has agreements to provide HALEU to companies including TerraPower LLC, the Bill Gates-backed reactor developer, and Oklo Inc.

(Updates with Centrus customers in last paragraph.)