Reducing Duration of Refueling Outage by Optimizing Core Design and Shuffling Sequence

Reducing the duration of refueling outage is possible by optimizing the core design and the shuffling sequence. For both options software tools have been developed that have been applied to the three most recent cycles of the Borssele plant in the Netherlands. Applicability of the shuffling sequence optimization to boiling water reactors has been demonstrated by a comparison to a recent shuffle plan used in the Hatch plant located in the United States. Their uses have shown that both core design and shuffling sequence optimization can be exploited to reduce the time needed for reloading a core with an in-core shuffling scheme. Ex-core shuffling schemes for pressurized water reactors can still have substantial benefit from a core design using a minimized number of insert shuffles.