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May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
Kenji Yokoyama, Makoto Ishikawa
Nuclear Science and Engineering | Volume 178 | Number 3 | November 2014 | Pages 350-362
Technical Paper | doi.org/10.13182/NSE14-11
Articles are hosted by Taylor and Francis Online.
To provide a reactor physics benchmark for burnup reactivity coefficients, experimental data, showing the relationship between excess reactivity and accumulated thermal power acquired during the experimental fast reactor JOYO MK-I duty power operation in the late 1970s, have been evaluated and analyzed. To improve the prediction accuracy of nuclear characteristics through the use of integral experimental data, nominal values and uncertainties, including correlations of the experimental data, were evaluated. All possible uncertainty factors were evaluated and quantified by utilizing knowledge obtained after the MK-I duty power operation and calculation results based on the latest reactor physics analysis methods. Meanwhile, the present evaluated data have been reviewed and approved by the International Reactor Physics Experiment Evaluation Project, with the expectation that these data will be widely used. In the present paper, the evaluation of nominal values and uncertainties is described with a focus on the measurement technique uncertainty, which is a dominant uncertainty factor of the burnup reactivity coefficient. In addition, new analysis results of the benchmark problem are shown by the use of the latest Japanese evaluated nuclear data JENDL-4.0.