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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.
K. S. Han, B. H. Park, A. Y. Aydemir, J. Seol
Fusion Science and Technology | Volume 75 | Number 2 | February 2019 | Pages 137-147
Technical Paper | doi.org/10.1080/15361055.2018.1554391
Articles are hosted by Taylor and Francis Online.
The Deal Two Equilibrium (DTEQ) code solves the Grad-Shafranov (GS) equation for magnetohydrodynamics equilibrium in the axisymmetric toroidal geometry using the deal.II finite element library. In this paper, we introduce DTEQ that can solve the GS equation both linearly and nonlinearly. The linear solution obtained from this code is verified by comparing with a known analytic solution of the linear GS equation. For the nonlinear solution, DTEQ requires two input profiles, p(ψ) and F(ψ), to be specified as a function of the normalized minor radius ρ. The pressure profile p(ψ) is specified based on Thomson scattering, charge exchange spectroscopy data, and an energetic particle pressure model. The toroidal field profile F(ψ) is obtained from our model that makes the diamagnetic current play a significant role when the poloidal beta βp is greater than one. With these two input profiles, the nonlinear GS equation can be solved using Picard iteration within the plasma boundary from EFIT. Using this newly developed code, we obtain several meaningful results that show its validity. The calculated poloidal current density is very large in the transport barrier due to the diamagnetic current, and the characteristics of the Pfirsch-Schlüter current appear in the toroidal current density. In addition, the results obtained from this code agree well with those from EFIT, and the calculated safety factor values in the center are well correlated with the sawtooth activity in the discharge.
