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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
F. D. Judge and P. B. Daitch
Nuclear Science and Engineering | Volume 26 | Number 4 | December 1966 | Pages 472-486
Technical Paper | doi.org/10.13182/NSE66-A18418
Articles are hosted by Taylor and Francis Online.
The variational method is used to reduce the general time-dependent Boltzmann equation to a multigroup (with overlapping or nonoverlapping) form. The variation of the fundamental decay rate with material properties is then studied. The relation between energy and space transients in pulsed multiplying and pulsed moderating systems is investigated. To augment the theoretical treatment of the asymptotic decay in a pulsed multiplying system, the Nelkin buckling expansion solution for the Fourier transformed transport equation for 1/υ absorption is extended to include non-1/υ absorption and fission. The development of an improved calculational procedure (DP-L multigroup overlapping or nonoverlapping) for determining the space and time dependence of the neutron flux in pulsed multiplying systems is described. This method is then applied to the analysis of recent pulsed spectra measurements. The duration of the energy and spatial transients and the variation of the vector flux distribution from the center to the edge of an assembly are described quantitatively. It is demonstrated that spatial asymmetries in the flux could exist after the flux distribution appears asymptotic.