REFUELING BOILING WATER-REACTORS

The leading position worldwide held by German nuclear power plants in the ranking order of energy production reflects the high technical and administrative standard of nuclear technology in Germany. However, th e coming deregulation of the energy markets is one of the factors whic h, by exerting pressure on electricity generating costs, require opera tors to reduce the costs of running their plants by further optimizing important processes. Among the most important of these expensive oper ating processes undoubtedly is inspection and maintenance, with a deci sive impact on plant availability. Shorter revision periods; in-plant maintenance; critical examination of the intervals of in-service inspe ctions: These are examples of approaches now debated worldwide to ensu re the modern, competitive operations of nuclear reactors. As a conseq uence of this trend, also refueling is being moved on the critical pat h of revision. Every hour saved in this step will directly improve pla nt availability and reduce generating costs. This particularly true of boiling water reactors whose more complicated core and fuel element d esigns, compared to those of pressurized water reactors, require more sophisticated refueling and shuffling procedures. The computer-assiste d refueling and shuffling process at Gundremmingen described in this a rticle allows idle trips of the fueling machine to be reduced and the number of necessary intermediate steps to be decreased. Optimization o f the planned sequence of steps is achieved by taking into account app licable rules and regulations in the underlying algorithm, not at the expense of safety. A higher degree of automation, up to direct compute r-controlled shuffling, offers additional options for the future which can speed up the refueling and shuffling process and, at the same tim e, can help avoid errors in these steps.