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Fusion Science and Technology
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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. V. Zhirkin, V. P. Budaev, A. V. Dedov, A. A. Glebova, A. O. Goltsev, A. T. Komov, B. V. Kuteev
Fusion Science and Technology | Volume 79 | Number 6 | August 2023 | Pages 703-722
Research Article | doi.org/10.1080/15361055.2023.2178869
Articles are hosted by Taylor and Francis Online.
The modern challenges of nuclear energy are the replenishment of dwindling reserves of nuclear fuel and the development of a closed nuclear fuel cycle while complying with strict radiation safety requirements. A fusion neutron source has unique capabilities to solve these problems. The preliminary results of a neutronic analysis of the FNS-C fusion-fission hybrid neutron source with a thorium-uranium aqueous blanket by the Monte Carlo method computer simulation, using the MCNP-4 code with the ENDF/B-VII cross-section library, gives satisfactory results for the study of the possibility of creating a compact source of fusion neutrons based on a small spherical tokamak for commercial use.
The obtained results show that the FNS-C hybrid blanket generates enough tritium to fully ensure the uninterrupted operation of the FNS-C throughout the year. The reproduction coefficient of 233U is 1.027 at a consumption of 1304 kg/year of the fissile material in the aqueous blanket containing 232Th enriched to 1.47% 233U. The FNS-C is operated with an effective neutron multiplication factor keff ~ 0.99 with reactivity ρ = –0.006249 in the presence of delayed neutrons, which corresponds to the safest state of the core of thermal neutron fission reactors. The thermal power of the FNS-C at keff ~ 0.99 is ~3 GW, which is comparable to the thermal power of fission reactors. This indicates the potential possibility of creating a safe thorium-uranium breeder power reactor based on a fusion neutron source. The results of the study were obtained for the simplified approximate geometrical FNS-C model. To confirm the preliminary results, it is necessary to develop a more accurate calculation model of the FNS-C machine.
