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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.
A. M. Tentner, A. Karahan (ANL), S. H. Kang (KAERI)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 823-835
The SAS4A safety analysis code, originally developed for the analysis of postulated Severe Accidents in Oxide Fuel Sodium Fast Reactors (SFR), has been significantly extended to allow the mechanistic analysis of severe accidents in Metallic Fuel SFRs. The SAS4A metal fuel models simulate the metal fuel thermo-mechanical and chemical behavior and track the evolution and relocation of multiple fuel and cladding components during the pre-transient irradiation and during the postulated accident, allowing an accurate description of the changes in the local fuel composition. The local fuel composition determines the fuel thermo-physical properties, such as freezing and melting temperatures, which in turn affect the fuel relocation behavior and ultimately the core reactivity and power history during the postulated accidents. Models describing the fuel-cladding interaction and eutectic formation, the effects of the in-pin sodium on the in-pin fuel relocation, and the post-failure reentry of the molten fuel and fission gas from the pin plenum have also been added. The paper provides on overview of the SAS4A key metal fuel models emphasizing the post-failure metal fuel relocation models included in the LEVITATE-M module of SAS4A. The capabilities of the SAS4A metal fuel models are illustrated through an extended SAS4A analysis of a postulated unprotected LOF-TOP accident in the metal fuel Prototype Gen-IV Sodium Fast Reactor (PGSFR). The results show that the maximum relative power reached during the postulated accident is 1.19 P0. The favorable characteristics of the metal fuel cause a significant decrease in net reactivity and relative power due to pre-failure in-pin fuel relocation. Negative net reactivity values persist after cladding failure, and the post-failure fuel relocation events occur at low and decreasing power levels.
