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Two steps forward for U.K. advanced nuclear
This week, two significant announcements have emerged from the United Kingdom’s advanced reactor sector.
On June 14, Rolls-Royce, the United Kingdom National Nuclear Laboratory, and the Japan Atomic Energy Agency announced that they had signed two trilateral memorandums of cooperation to collaborate on “advanced modular reactor (AMR) technology, specifically high-temperature gas-cooled reactors (HTGR), and the coated particle fuel these reactors will use.”
Separately, on June 16, Bellevue, Wash.–based TerraPower announced that its Natrium reactor design has been formally submitted for U.K. regulatory review. The company also announced the formation of a new subsidiary, TerraPower UK Ltd.
Gregory A. Johnson
Nuclear Technology | Volume 170 | Number 3 | June 2010 | Pages 416-421
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT10-A10327
Articles are hosted by Taylor and Francis Online.
Transuranic (TRU) conversion ratio is a key cost driver of the advanced fuel cycle. The reactor capacity required to consume the national TRU inventory increases as conversion ratio increases. Achieving zero conversion ratio with metal alloy or oxide fuels is fraught with technical challenges. These difficulties can be overcome by hydriding the metal alloy fuel. In this paper, we present the novel concept of using a uranium-free hydrided metal alloy fuel to achieve zero conversion ratio. A reactor core composed of this novel fuel and that would fit in the Sodium Advanced Fast Reactor core geometry was developed; core performance and TRU consumption is estimated and presented. Concerns about the safety of uranium-free fuels are addressed. Although the Doppler effect is nonexistent in a uranium-free fast core, a substantial Doppler effect is present with the uranium-free hydrided metal alloy fuel.