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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
R. van Geemert, F. Jatuff, F. Tani, R. Chawla
Nuclear Science and Engineering | Volume 148 | Number 1 | September 2004 | Pages 162-171
Technical Paper | doi.org/10.13182/NSE04-A2448
Articles are hosted by Taylor and Francis Online.
With reactivity being the most important integral reactor physics quantity - and simultaneously the one that can be measured with the highest accuracy - there is a great interest in understanding how possible space- and energy-dependent data and/or modeling discrepancies may propagate into a calculated reactivity change, and with which magnitude this occurs. In the context of pin removal reactivity effects in a light water reactor assembly, for example, it is illustrative to carry out, for any arbitrary localized material composition perturbation, a decomposition of the total effect into individual space- and energy-dependent contributions of the different unit cells in the assembly. If this decomposition is normalized to +100% in the case of a positive reactivity effect and to -100% in the case of a negative reactivity effect, an importance map is established that indicates the relative contribution (in percent) of each individual contributing cell to the total reactivity effect caused by the localized material composition change. Such an importance map can be interpreted as a sensitivity matrix that quantifies the final discrepancy in a calculated reactivity effect, with respect to its reference value, as a weighted sum of the complete collection of cell-wise data and/or modeling discrepancies. The current paper outlines the basic theory and gives certain practical applications of the proposed decomposition methodology. Thus, it is found that the developed methodology offers in-depth, quantitative explanations for calculational discrepancies observed in the analysis of fuel pin removal experiments conducted in the framework of the LWR-PROTEUS program at the Paul Scherrer Institute.