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Getting back to yes: A local perspective on decommissioning, restart, and responsibility
For 45 years, Duane Arnold Energy Center operated in Linn County, Ia., near the town of Palo and just northwest of Cedar Rapids. The facility, owned by NextEra Energy, was the only nuclear power plant in the state.
In August 2020, a historic derecho swept across eastern Iowa with winds approaching 140 miles per hour. Damage to the plant’s cooling towers accelerated a shutdown that had already been planned, and the facility entered decommissioning soon after, with its fuel removed in October of that year. Iowa’s only nuclear plant had gone off line.
Today the national energy landscape looks very different than it did just six short years ago. Electricity demand is rising rapidly as data centers, artificial intelligence infrastructure, advanced manufacturing, and electrification expand across the country. Reliable, carbon-free baseload power has become increasingly valuable. In that context, Linn County has approved the rezoning necessary to support the recommissioning and restart of Duane Arnold and is actively supporting NextEra’s efforts to secure the remaining state and federal approvals.
Akio Yamamoto, Tomohiro Endo, Go Chiba, Kenichi Tada
Nuclear Science and Engineering | Volume 196 | Number 11 | November 2022 | Pages 1267-1279
Technical Paper | doi.org/10.1080/00295639.2022.2087833
Articles are hosted by Taylor and Francis Online.
The resonance upscattering effect (the thermal agitation effect) is implemented in the generation capability of multigroup neutron cross sections of the FRENDY nuclear data processing system. The resonance upscattering effect is considered by (1) the variation of self-shielding factors (effective cross sections) due to the change in the ultra-fine group spectrum and (2) the variation of group-to-group elastic scattering cross sections. Since the upscattering effect is considered in the ultra-fine group spectrum calculation, an iteration calculation is necessary to consider the upscattering. The impacts of the iteration strategy (Jacobi or Gauss-Seidel), as well as the number of iterations, are discussed. In the verification calculations, impacts on the ultra-fine group spectrum, effective cross sections, and neutronics characteristics (the Doppler effect) are confirmed. The effect of energy group structure and the impact of resonance upscattering treatments on the Doppler effect through the variation of effective cross sections and the elastic scattering matrix are investigated. The results indicate that FRENDY can provide appropriate multigroup cross sections considering the resonance upscattering effect.
