ATF Solutions to Light Water-Cooled SMRs

This project is a collaborative effort between universities, a national laboratory, and industry partners across the US and UK. The project aims to assess the benefits and implications of using Accident-Tolerant (or Advanced Technology) Fuels, or ATFs, in a variety of Small Modular Reactor (SMR) designs.
ATFs have the potential to significantly improve safety and economic performance of reactors. The increased safety margin that they offer can be translated into either more straightforward and short licencing process, and relaxation of requirements on safety equipment, or substantial power uprate, or both - all ultimately leading to cost savings.
Multiple ATF concepts have been proposed in recent years, offering a range of potential performance improvements. Their technology readiness level, however, also varies widely - from conceptual ideas to nearly commercially available products already being marketed to the industry. SMR designs are equally diverse. Even though they may share many features of Light Water Reactor technology, they differ substantially in size, coolant circulation driving force (natural or forced convection), arrangement of primary coolant loop components (integral or loop), approach to reactivity control etc. Therefore, the benefits ATFs can offer if used in these SMRs will differ. The main objective of this project is to quantify these benefits for a subset of promising SMR-ATF combinations.
UK Government have committed significant financial support to the development of SMR technology proposed by Rolls-Royce as part of its overall net-zero decarbonisation strategy. Furthermore, substantial expertise in nuclear fuel manufacturing and other fuel cycle services are considered strategic assets for the UK. The UK research team contributing to this project in partnership with Rolls-Royce and Westinghouse-Springfields will focus on the analysis of ATF options applied to the UK-based Rolls-Royce SMR. We will assess and compare the ATF options with respect to their in-core neutronic and thermal-hydraulic behaviour under normal operation, transients, and accident conditions, as well as compare their effects on the back end of the fuel cycle. This project will help to guide the future Rolls-Royce SMR and ATF development effort both nationally and internationally.