A sensitivity study on fast reactor scenarios with various conversion ratios

Korean fast reactor scenarios have been analyzed for various kinds of conversion ratios by the DANESS system dynamic analysis code. The once-through fuel cycle analysis was modeled based on the Korean “National Energy Basic Plan” up to 2030 and a postulated nuclear demand growth rate until 2150. The fast reactor scenario analysis has been performed for three kinds of conversion ratios such as 0.3, 0.61, and 1.0. Through the calculations, the nuclear reactor deployment scenario, front-end cycle, back-end cycle, and long-term heat load have been investigated.From the once-through results, it is shown that the nuclear power demand would be ∼70 GWe, and the total amount of the spent fuel accumulated by 2150 would be ∼168,000 t. Also, the fast reactor scenario analysis results show that the spent fuel inventory and out-pile transuranic element can be reduced by increasing the fast reactor conversion ratio. Furthermore, the long-term heat load of spent fuel decreases with an increase in the conversion ratio. However, it is known that the deployment of a fast reactor of a low conversion ratio does not reduce much the spent fuel and out-pile transuranic element inventory due to the fast reactor deployment limitation which is related to the availability of transuranic elements.