Key technological challenges for JSFR development

JSFR is a sodium cooled loop type fast reactor on which a conceptual design study is now underway in the framework of 'Fast Reactor Cycle Technology Development Project (FaCT project)' of Japan. Achieving economic competitiveness with future light water reactors, along with assuring high level of safety and reliability, is among the most crucial development targets. A number of innovative technologies are pursued for these purposes. A two loop primary heat transfer system (PHTS) design, integration of a main circulation pump and an intermediate heat exchanger (IHX) into one single component, and adoption of high chrome ferritic steel as a structural material are typical technologies mainly for economic purposes. A passive shutdown system, decay heat removal by natural convection, and re-criticality free core configuration are those for mainly safety enhancement purposes. Technically challenging issues inevitably accompany these innovative technologies, and a systematic research and development program is undertaken for resolving these issues and realization of the plant design. An overall picture will be given in this paper on the design concept of JSFR that will be followed by descriptions on the major innovative technologies and their relevant research and development activities. (author)