Design Study and R&D Progress on Japan Sodium-Cooled Fast Reactor

This paper describes the progress of the design study and research and development (R&D) for the Japan Sodium-cooled Fast Reactor (JSFR) implemented in the "Fast Reactor Cycle Technology Development (FaCT)" project. A sodium-cooled fast reactor with an electric power of 1,500 MWe is targeted for commercialization at around 2050, and a demonstration reactor assuming a power output from 500 to 750 MWe is planned to start operation at around 2025. R&D on innovative technologies to achieve economic competitiveness and enhance reliability and safety is carried out for the commercialization. A compact reactor vessel without a vessel wall cooling system is pursued in consideration of the wall thickness enough to resist the severest seismic condition. A two-loop cooling system with shortened high-chromium steel piping is a crucial feature, and studies on the hydraulics in the pipe elbow and the fabrication capability of the pipes are being carried out. A double-walled straight tube steam generator is investigated to enhance the reliability against sodium/water reaction, and developmental works are progressing, including the thermal-hydraulic design and trial manufacturing for components. Self-Actuated Shutdown System (SASS) is being developed with safety analysis of the applicability for JSFR and experimental demonstration in the experimental fast reactor JOYO. An advanced fuel handling system is pursued to enhance economic performance. In parallel with considering the necessity of studies on alternative technologies, discussion on whether the innovative technologies can be adopted for JSFR is in progress to be finalized in 2010.