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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE fast tracks test reactor projects: What to know
The Department of Energy today unveiled 10 companies racing to bring test reactors online by next year to meet Trump's deadline of next Independance Day, leveraging a new DOE pathway that allows reactor authorization outside national labs. As first outlined in one of the four executive orders on nuclear energy released by President Trump on May 23 and in the request for applications for the Reactor Pilot Program released June 18, the companies must use their own money and sites—and DOE authorization—to get reactors operating. What they won’t need is a Nuclear Regulatory Commission license.
S. Bian
Nuclear Technology | Volume 41 | Number 3 | December 1978 | Pages 401-407
Technical Note | Reactor | doi.org/10.13182/NT78-A32124
Articles are hosted by Taylor and Francis Online.
A rod ejection accident introduces a large positive reactivity insertion in a core, causing a large power excursion. The point kinetics method is usually used to analyze this type of accident. The reactivity changes due to Doppler effect are usually obtained by static neutronics calculations with nominal (pre-ejection) core flux shapes for different fuel temperatures. The effect of locally peaked shapes due to the rod ejection is not included in the Doppler reactivity calculation. The resultant Doppler reactivity feedback is considerably underestimated, while the magnitude of the power excursion is overestimated. A simplified method that incorporates the local flux peaking effect on the Doppler feedback in a point kinetics code has been developed. The results based on this weighted Doppler feedback compare favorably with a three-dimensional kinetics analysis.