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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.
Charles N. Kelber and Philip H. Kier
Nuclear Science and Engineering | Volume 26 | Number 1 | September 1966 | Pages 67-72
Technical Paper | doi.org/10.13182/NSE66-A17188
Articles are hosted by Taylor and Francis Online.
A model is developed for the estimation of the Doppler effect from the unresolved energy region for fissile nuclides. For energy intervals that contain enough resonances for the reaction rates to be statistically independent of neighboring intervals, many resonance structures, or ladders, are generated by a random process that preserves the average widths and strength function. For each ladder, the relative changes in the absorption and the fission rates with temperature are computed, including overlap effects. This procedure yields estimates of mean quantities and the dispersion of values about the mean when the reaction rates are regarded as random variables. The Doppler effect and its variance are obtained by incorporating these resonance integral calculations into a multigroup-perturbation theory formulation., This model has been used to estimate the Doppler effect for 239Pu in the Codd and Collins mixture. For a temperature change from 300 to 600°K, the contributions to Ak/k from the unresolved region (215 eV to 10 keV) and the resolved region ( < 215 eV) were calculated to be 290 X 10"6 and 440 X10-6, respectively. The probable error, or ^2/3 standard deviation in the Doppler effect, assumed to be solely from the unresolved region, was ± 290 X 10" 6.