Conceptual design of fast breeder reactors cooled by supercritical steam

The conceptual designs of a supercritical steam-cooled fast breeder reactors (indirect and direct cycle) are carried out as a step toward low cost FBR plants. The advantages of supercritical steam cooling are: high thermal efficiency, simplified system, low pumping power and well-experienced water technology in fossil-fired plants. The partial and whole core negative void reactivity are realized by our novel concept, inserting thin zirconium-hydride layers between the seeds and blankets. The net electric power is more than 1000 MWe. The breeding performances are satisfactory, CSDT<30 years. These design goals were not satisfied simultaneously in the past steam-cooled FBRs. (author)