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Swiss nuclear power and the case for long-term operation
Designed for 40 years but built to last far longer, Switzerland’s nuclear power plants have all entered long-term operation. Yet age alone says little about safety or performance. Through continuous upgrades, strict regulatory oversight, and extensive aging management, the country’s reactors are being prepared for decades of continued operation, in line with international practice.
R. A. Matzie, D. C. Leung, Y. Liu, R. W. Beekmann
Nuclear Technology | Volume 52 | Number 2 | February 1981 | Pages 189-197
Technical Paper | Fuel Cycle | doi.org/10.13182/NT81-A32664
Articles are hosted by Taylor and Francis Online.
Nuclear reactors are inherently capable of operating for a substantial period beyond their nominal end of cycle (EOC) as a result of negative moderator and fuel temperature coefficients and the decrease in xenon poisoning with lower core power levels. This inherent capability can be used to advantage to reduce annual uranium makeup requirements and cycle energy costs by the use of planned EOC stretchout. The benefits of planned stretchout are assessed in the context of extended-burnup fuel cycles for two methods of operation: normal power coastdown and feedwater-pressure augmentation (FWPA). In the latter method, feedwater temperature is reduced allowing extended operation at full rated core power but at a lower thermal efficiency. The extent to which FWPA can be practiced is limited, primarily, by turbine operating conditions, resulting in a differential benefit in uranium utilization of only ∼0.5% above that of normal power coastdown.