Idaho Nationwide Laboratory (INL) has fabricated roughly two dozen commercial-grade gas pellets of high-assay low-enriched uranium (HALEU) uranium dioxide (UO2), the Division of Vitality (DOE) revealed on Nov. 20. The milestone demonstrates the nationwide laboratory’s “distinctive capability” to supply custom-made nuclear gas for business and authorities companions, the DOE stated.
INL stated researchers on the Experimental Fuels Facility on the Materials and Fuels Complicated in Idaho fabricated about two dozen pellets of UO2 HALEU in “early 2023.” The specialised pellets comprise gas enriched to fifteen% uranium-235.
Whereas standard gentle water reactor (LWR) fuels are sometimes enriched to lower than 5% uranium-235—a restrict allowed by most current Nuclear Regulatory Fee (NRC) working licenses—HALEU enrichment wants ranges of between 5% and 19.75%. As a result of HALEU is enriched greater, it could present extra energy per quantity than standard reactors, and its effectivity permits for smaller plant sizes. The gas sort additionally guarantees longer core life and a better burn-up price of nuclear waste. Many superior nuclear reactor designs, together with 9 of the ten designs awarded underneath the DOE’s Superior Reactor Demonstration Program (ARDP), require HALEU.
One other 100 to 150 Pellets Will Be Fabricated
INL fabricated its pellets utilizing a conventional powder metallurgy course of, “a pressure-less sintering method just like that utilized by business to make gentle water reactor gas,” it stated. Researchers at the moment are testing the gas pellets to guage their properties and determine impurities.
Plans then name for the fabrication of one other 100 to 150 pellets to assist testing of a specialised cladding developed by Normal Electrical’s International Nuclear Fuels (GNF) in INL’s Superior Check Reactor. The venture, funded underneath the DOE’s Accident Tolerant Gasoline Program, is predicted to “improve the efficiency of current gentle water reactors and future superior reactors.”
However, in keeping with INL, the milestone is extra important as a result of demonstrating UO2 HALEU might pave the best way for the event of different varieties of HALEU, together with metallic and ceramic sorts. Testing gas is a vital precursor to acquiring NRC licensing, it famous.
“The pellets that we produced had been extraordinarily excessive density,” famous Jennifer Watkins, a nuclear fuels and supplies scientist at INL, who led the venture. “Our preliminary characterization efforts recommend they may meet all business requirements for uranium dioxide.”
Firming Up the HALEU Provide Chain
The milestone additionally “highlights INL’s capability to tailor enrichments to buyer and experiment necessities,” the lab stated earlier this week. Demonstrating the potential to manufacture a business high quality of HALEU UO2 “gives choices for business and different authorities businesses to make gas samples with a wider vary of enrichment with out impacting current working licenses,” it added. The venture’s success additionally “establishes INL because the go-to customized HALEU gas fabricator for reactor firms,” it stated.
INL’s introduced achievement is the most recent of a collection of milestones in concerted efforts by the facility business and authorities to develop a HALEU provide chain. The DOE posits greater than 40 metric tons of HALEU could also be wanted by 2030 to deploy a brand new fleet of superior reactors in a timeframe that helps net-zero emissions targets by 2050.
Centrus Vitality, a agency underneath a DOE contract to display manufacturing of HALEU with home expertise, in October 2023 kicked off enrichment operations at its American Centrifuge Plant cascade in Piketon, Ohio—the nation’s solely NRC-licensed HALEU facility. Earlier this month, the nuclear gas and providers agency delivered its first batch of HALEU uranium hexafluoride (UF6, 19.75% enriched) to the DOE.
That milestone marked the completion of the primary section of a multiphase settlement with the DOE awarded in November 2022. Section 1 of the contract known as for the completion of Centrus’s 16-centrifuge cascade and the beginning of operations to provide an preliminary 20 kilograms (kg) of HALEU UF6 (19.75% enriched) by December 31, 2023. Underneath Section 2, Centrus plans to proceed manufacturing for a full 12 months at an annual manufacturing price of 900 kg of HALEU.
Section 1 included a 50% price share requirement for Centrus, and the corporate and the DOE every contributed about $30 million of the $60 million total price. In Section 2 of the contract, the DOE pays Centrus on “a cost-plus incentive price” foundation for the HALEU the corporate produces. Nevertheless, the DOE will personal the HALEU produced from the demonstration cascade. The operation contract additionally offers the DOE choices to pay for as much as 9 extra years past the bottom contract (although these choices will probably be topic to the supply of Congressional appropriations).
Nevertheless, Centrus is individually additionally exploring the potential for scaling up the Piketon facility for expanded HALEU manufacturing. “The capability of the 16-centrifuge cascade is modest—about 900 kg of HALEU per 12 months—however with adequate funding and offtake commitments, Centrus might considerably develop manufacturing,” the corporate famous. A full-scale HALEU cascade, comprising 120 centrifuge machines has a mixed capability to provide roughly 6,000 kg of HALEU per 12 months (6 MTU/12 months). It “could possibly be producing HALEU inside 42 months after securing the mandatory funding,” Centrus stated. “With applicable assist, Centrus might add a second HALEU cascade six months later and subsequent cascades each two months after that.”
—Sonal Patel is a POWER senior affiliate editor (@sonalcpatel, @POWERmagazine).
