The U.S. Department of Energy’s National Nuclear Security Administration has completed the conversion of the Kyoto University Critical Assembly Core C from proliferation-sensitive highly enriched uranium to high-assay low enriched uranium fuel.
Switching to HALEU fuel will enable KUCA’s Core C to perform advanced research and human resource development missions with a lower proliferation risk compared to operations using HEU, which can be used as a nuclear weapon component. Changing the geometry and composition of the fuel assembly allows researchers to study various reactor concepts, the department said Tuesday.
Kasia Mendelsohn, principal assistant deputy administrator for defense nuclear nonproliferation at the Energy Department, said the partnership enables the United States and Japan to deliver on their shared commitment to minimizing HEU. “Through our close cooperation, NNSA and our partners were able to overcome the barriers to success,” she said. “We are grateful to the entire multilateral team for seeing it through.”
The conversion project, in partnership with Japan’s Kyoto University, began in the late 2000s as part of the U.S.-Japanese collaboration on nuclear nonproliferation. It encountered challenges in the design, transportation and regulatory approval of the HALEU fuel, but those were resolved with support from NNSA national laboratories, Japan’s science and technology ministry MEXT, Kyoto University, Framatome CERCA and other partners.
The project to convert KUCA’s Cores A and B is in the advanced stages.