Investigation on daily load following operation in sodium cooled fast reactor

相澤 康介 ; 近澤 佳隆  ; 諸星 恭一*; 久保 幸士*; 内田 昌人*

Aizawa, Kosuke; Chikazawa, Yoshitaka; Morohoshi, Kyoichi*; Kubo, Koji*; Uchita, Masato*

Next-generation innovative reactors have a new value of their flexibility with variable renewable energy. One way for achieving efficient energy supply in sodium cooled fast reactors while considering coexistence with renewable energy sources whose electrical output fluctuates is to carry out daily load following operation. However, daily load following operation generates temperature and level fluctuations in sodium as a coolant. Thus, the thermal stress occurs near the level of sodium in the reactor vessel by conducting daily load following operation. In this study, the feasibility range of daily load following operation was evaluated from the viewpoint of structural integrity for pool-type sodium cooled fast reactor. In the evaluation of structural integrity, the part where the structural integrity was expected to be most severe due to thermal stress caused by daily load following operation was selected as the evaluation target. From the evaluation results, the feasibility range of daily load following operation in pool-type sodium cooled fast reactor was confirmed.