Possibility to stabilize plutonium inventory in a sodium-cooled small modular reactors – Pressurized water reactors fleet

Abstract

Scenarios studies have proven the fuel cycle closure feasibility with fleet composed by PWRs and large fast reactors. Nevertheless, large reactors may not be adapted to low or scalable electricity needs (off-grid cities, high renewable share, desalination plant, etc…). Sodium-cooled Small Modular Reactors (SMRs-Na) could be an interesting answer to these needs. However, they tend to be plutonium burners and not breeders, which is contradictory with fuel cycle closure. In this paper, a 400 MWth SMR-Na is used to study PWR-SMR-Na fleet at steady state. It appears that plutonium equilibrium is achievable in such fleet either with the initial SMR-Na design and several constraints on reprocessing strategy (complete separation of all plutonium sources) or by adding axial and radial fertile blankets with a less constrained reprocessing strategy. Then, a comparison with a PWR-SFR fleet shows that SMR-Na could be easier to deploy but at the cost of a greater plutonium inventory.