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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.
Masaoki Komata
Nuclear Science and Engineering | Volume 64 | Number 4 | December 1977 | Pages 811-822
Technical Paper | doi.org/10.13182/NSE77-A14496
Articles are hosted by Taylor and Francis Online.
A generalized perturbation theory is established for the surface perturbation problem in which a boundary parameter or a boundary shape is disturbed. Mainly handled is a multidimensional Sturm-Liouville-type equation and finally discussed is a multigroup diffusion model. The theory is based on Green's theorem and provides perturbation formulas that have simple forms of surface integrals and are explicitly related to a deviation of boundary parameters. The formulas are connected with a quantity within a volume through the surface Green's function. The effects of surface perturbation on a solution (a neutron flux distribution) of the equation itself, on a linear functional of direct solution, and on a ratio of linear functional of direct solution are shown. The theory is also applied to a ratio of linear functional of adjoint solution and to a ratio of bilinear functional of direct and adjoint solutions. Perturbation formulas are also derived from Pomraning's variational principle, and it is shown that the formulas are identical with those based on Green's theorem. The Lagrange multipliers used in the variational principle are explained as integrated Green's functions.