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2024 ANS Winter Conference and Expo
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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.
J. T. Wajima, H. Yamamoto, H. Kikuchi, T. Ohnishi, S. Kobayashi
Nuclear Science and Engineering | Volume 31 | Number 1 | January 1968 | Pages 19-31
Technical Paper | doi.org/10.13182/NSE68-A18004
Articles are hosted by Taylor and Francis Online.
The microparameters including the thermal-neutron disadvantage factor, DF, the epi- to sub-Cd neutron capture ratio in 238U, ρ28, the epi- to sub-Cd fission ratio in 235U, δ25, and the ratio of the epi-Cd 238U fission to the sub-Cd 235U fission, δ28, were measured in the Ozenji Critical Facility for a seven-rod clustered nuclear superheat fuel element. The factors f, p, and ϵ were derived therefrom and the effect of 235U epithermal fissions on the neutron multiplication factor was observed to be 1.5% Δk/k. Flooding changed the individual factors f, p, and ϵ by amounts corresponding to −6.8% Δk/k, +4.7% Δk/k, and −2.9% Δk/k, respectively, yielding an overall change of −5.1% Δk/k. The maximum discrepancies between measurement and calculation are 1 to 3% for DF, ρ28 , δ25, and δ28; 0.3% Δk/k for f, p, and ϵ; and 0.4% Δk/k for the infinite multiplication factor. The calculation of the effects of flooding on f, p, ϵ, and the infinite multiplication factor agrees with the experiment to within 0.3 to 0.4% Δk/k. When performing the cell calculations, care was taken to determine how to cylinderize the unit cell to perform the one-dimensional calculations with the THERMOS code, how to select the value of the L factor to be used in the JUPITER code (modified MUFT) and how to incorporate the heterogeneous effect of fast fissions.
