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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.
Alan M. Winslow
Nuclear Science and Engineering | Volume 32 | Number 1 | April 1968 | Pages 101-110
Technical Paper | doi.org/10.13182/NSE68-A18829
Articles are hosted by Taylor and Francis Online.
A formulation of asymptotic neutron diffusion theory for numerical calculations is presented which provides in simple ways for physical features not included in the elementary form of the theory. These are: 1) exponential time dependence, which is provided for by a transformation to steady state; 2) effect of surface curvature on the linear extrapolation length, provided for by means of the principal radii of curvature; 3) material discontinuities, provided for by limiting the current at an interface to its free surface value; and 4) prescribed sources and velocity dependence, provided for by a generalization of the number of secondary neutrons per collision. Numerical results are presented showing that the form of time-dependent multigroup neutron diffusion theory thus obtained is more accurate than the ordinary multigroup formulation especially for small or inhomogeneous systems.