Core concept of Innovative Water Reactor for Flexible Fuel Cycle (FLWR)

Okubo, Tsutomu; Uchikawa, Sadao; Kugo, Teruhiko ; Akie, Hiroshi  ; Iwamura, Takamichi

In order to ensure sustainable energy supply in the future based on the matured LWR technologies, a concept of Innovative Water Reactor for Flexible Fuel Cycle (FLWR) has been investigated in JAERI. The concept consists of two parts in the chronological sequence. The first part realizes a high conversion type core concept, which is basically intended to keep the smooth technical continuity from current LWR technologies without significant gaps in technical point of view. The second part represents the Reduced-Moderation Water Reactor (RMWR) core concept, which realizes a high conversion ratio more than and around 1.0 being useful for the long-term sustainable energy supply through plutonium multiple recycling based on the well-experienced LWR technologies. The key point is that the two core concepts utilize the compatible and the same size fuel assemblies, and hence, the former concept can proceed to the latter in the same reactor system based flexibly on the fuel cycle circumstances during the reactor operation period around 60 years.