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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.
Qiuran Wu, Peng Lu, Hua Du, Yu Zheng, Songlin Liu
Fusion Science and Technology | Volume 79 | Number 3 | April 2023 | Pages 274-283
Technical Paper | doi.org/10.1080/15361055.2022.2120304
Articles are hosted by Taylor and Francis Online.
Radiation field analyses of the fusion reactor are vital to machine design and personal/environmental irradiation protection. Owing to the complicated and toroidal symmetry of fusion reactors, these nuclear analyses have been performed based on a sector model with reflecting boundary conditions. However, not all sections of a fusion reactor are symmetrical in the toroidal direction, particularly the neutron flow channels introduced by auxiliary systems from which particles can leak directly from the plasma. Hence, the reflecting boundary conditions cannot accurately describe the particle transport. Consequently, radiation field analyses based on a full-sector model must be performed to verify the results obtained. In this regard, the neutronics model of CFETR has been built in 360 deg. Meanwhile, the development of the automatic geometry conversion platform cosVMPT has enabled an entire 360-deg model of the CFETR to be established. The model contains all primary components and the outer house building. Sixteen upper/lower ports and six equatorial ports are included, in which two of them are slanted for neutral beam injection, whereas the other ports are filled with a shielding block. The on-the-fly (OTF) global variance reduction method is utilized to accelerate neutron/photon coupling transport. The results show that cosVMPT and the OTF method are reliable, and that the obtained neutron/photon flux is asymmetric outside the main machine. The computational results of the 360-deg model are compared with those of the sector model such that the application scope of simplifying the modeling and calculation using the sector model can be further confirmed.