10. NUCLEAR

Production of enriched uranium

The DOE is providing support to produce high-assay low enriched uranium (HALEU) to accompany the development of advanced reactors. HALEU fuel (enrichment from 5% up to 20% uranium-235 [U235]) differs from that used in the existing LWR fleet (enrichment typically between 3.5% and 5% U235), and has many advantages that improve reactor performance. Because U235 is more concentrated, the fuel assemblies and reactors can be smaller, which is one reason many SMR designs will run on HALEU. The reactors do not need to be refuelled as often, and they can achieve higher “burnup” rates, which means less fuel will be required and less waste will be produced.

Accident tolerant fuels

As part of the policy to encourage innovations in the nuclear industry, on a cost-shared basis, the DOE awarded in January 2019 over USD 111 million to three industry partners to develop accident tolerant fuel (ATF). Additional funding is planned in future fiscal years. ATFs are meant to provide additional safety margins, and improved reliability and economics for NPPs, for example by enabling more significant ramping of nuclear power (flexible operation), a mode of operation that could be required more often in future electricity systems with large shares of variable renewable generation. While the US nuclear fleet has operated principally as baseload generation, flexible operation of NPPs is not new, with significant operational experience in France and Germany. An added feature of ATF would be to offer an additional “grace period” to operators of NPPs in the event of a nuclear accident with loss of cooling and/or loss of external power, providing time to bring on emergency cooling and power systems. DOE funding is aimed at ensuring demonstration of test assemblies in a commercial NPP, as well as preparing for the licensing of such fuels, in co-operation with the NRC.

Innovation, nuclear research, human resources, education

Developing human resources, competences and research facilities is key to supporting US ambitions to regain leadership in civil nuclear technologies. The administration recognises this, and has put in place a suite of initiatives, including the Gateway for Accelerated Innovation in Nuclear (GAIN) initiative. The GAIN initiative was launched in November 2015 to provide a way to fast-track nuclear innovation, providing stakeholders with a means of accessing DOE research and development (R&D) infrastructure to help them meet the challenges of bringing new technologies towards engineering-scale demonstration and market deployment (also see Chapter 6, “Energy Technology Research, Development and Demonstration”).

Versatile Test Reactor

The DOE is supporting the design and promoting the construction of a new research facility, a flexible materialand fuel-testing reactor based on sodium-cooled fast reactor technology (one of the six Generation IV technologies). This facility, called the Versatile Test Reactor, will be located at the INL. The project, which was included in the Nuclear Energy Innovation Capabilities Act of 2017 (formally enacted into law in September 2018), was officially launched in February 2019. It will provide the United States with the domestic capability to test and qualify advanced fuels and materials that are essential

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