Maturity of the accident-tolerant fuel concepts: the fuel cycle and used fuel disposition

Abstract This chapter presents an educated, yet subjective maturity evaluation of the five accident-tolerant fuel (ATF) concepts discussed in Chapters 4–7. The five evaluated fuel concepts include three cladding concepts (chromium-coated zirconium alloy, FeCrAl alloys, and silicon carbide composites) and two fuel concepts including modified urania fuel and high-density fuels. The rating of the maturity level of the concepts has been conducted using metrics from technical readiness level principles by a panel of international nuclear materials experts, mainly from the nuclear energy agency. Not surprisingly the highest maturity level corresponded to the two evolutionary concepts which may have a better chance to obtain near-term licensing from the regulatory entities. These two nearest term concepts include chromium-coated zirconium alloy for cladding and chromia-doped urania for fuel. The second nearest term cladding concept was the monolithic iron–chromium–aluminum FeCrAl alloy. The other two concepts, namely silicon carbide for cladding and higher uranium density for fuel, have a much longer term possibility of implementation in a commercial power reactor owing to the many technical issues that still need to be solved. A positive twist is that a ceramic silicon carbide design can be first implemented for channel boxes in BWRs as a near- to mid-term ATF concept. This will allow for data gathering in an actual reactor environment, which may accelerate the subsequent implementation of SiC/SiC CMC as cladding for the fuel.