Progress and issues on development of reduced-moderation water reactors; Aiming at multiple recycling and breeding of plutonium based on light water reactor technologies

Okubo, Tsutomu; Morooka, Shinichi*; Takeda, Renzo*

Reduced-Modeartion Water Reactors are attractive reactor concepts, which enable plutonium multiple recycling and/or breeding based on Light Water Reactor tecnologies. Since they introduce the tight-lattice fuel rod configuration, there are some related issues such as heat removal capability and void reactivity coefficient, which tends to become positive value. In recent years, a lot of technical knowledge have been accumulated, and hence, technical development on these issues has been proceeded, being also supported by the governmental competitive budget program by MITI and MEXT. This article summarizes accumulated technical knowlege and the future issues.