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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.
J. Seol, K. C. Shaing
Fusion Science and Technology | Volume 78 | Number 2 | February 2022 | Pages 111-118
Technical Paper | doi.org/10.1080/15361055.2021.1960090
Articles are hosted by Taylor and Francis Online.
Since the magnetic field strength is not constant on the magnetic flux surface, the flow also varies so that the density compression occurs along the poloidal direction. Since the inhomogeneous flow causes the density compression in the poloidal direction, the parallel flow is also perturbed. In this study, we investigate the effects of the parallel flow perturbation on the geodesic acoustic mode (GAM) when it is described by the kinetic approach. Using the continuity equation, it is shown that the flow perturbation in the geodesic curvature direction is balanced by the lowest-order term of the density perturbation in , and the flow perturbation in the parallel direction is balanced by the higher-order terms of the density perturbation. Since the density perturbation includes both the perpendicular and parallel flow perturbation contributions, the GAM frequency obtained by the kinetic approach has the parallel flow perturbation contribution, which is 1/ term in the GAM frequency equation. The low frequency branch of the dispersion relation is also discussed to demonstrate the connection between the GAM theory and neoclassical theory for the first time. It is shown that the flow perturbation in the geodesic curvature direction is balanced mostly by the parallel flow perturbation. It means that the flow in the flux surface is divergence free approximately as in the usual transport ordering. Thus, the poloidal flow goes to the neoclassical flow when the low frequency branch is taken.
