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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.
Seyed Mohammad R. Nejat
Nuclear Technology | Volume 103 | Number 2 | August 1993 | Pages 187-198
Technical Paper | Fission Reactor | doi.org/10.13182/NT93-A34842
Articles are hosted by Taylor and Francis Online.
The 5-MW highly enriched uranium (HEU)-fueled Tehran Research Reactor is considered for conversion to high-density, low-enriched uranium (LEU) fuel. A preliminary neutronics calculation is performed as part of the conversion goal. In this study, two cores are considered: the HEU reference core and a proposed LEU core similar to the reference core, using standardized U3Si2 plates with the option of different 235U loadings. Various possibilities are investigated for the conversion of HEU to LEU fuel elements with 20% enriched 235U loadings of 207 to 297 g 235U/element. For the same equilibrium cycle length, the fuels are compared for flux, power distribution, burnup, and reactivity.