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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.
Dong H. Nguyen
Nuclear Science and Engineering | Volume 50 | Number 4 | April 1973 | Pages 370-381
Technical Paper | doi.org/10.13182/NSE73-A26572
Articles are hosted by Taylor and Francis Online.
The stability of a nuclear reactor with prompt feedback is examined when its eigenvalue (size, material buckling) is increased or decreased. Two models describing the temperature dependence of the Doppler coefficients T-1 and T-3/2 are used in the analysis, and their relative effectiveness in maintaining stability is compared. Both the eigenvalue and neutron flux of the nonlinear reactor are expanded in the perturbation parameter ∈, defined as the spatially weighted average of the change in neutron flux relative to the flux of the linear reactor. For a change in reactor eigenvalue, the equilibrium states of the neutron flux are obtained, accurate to the first order of feedback, but to an arbitrary order of perturbation. The stability of each state is examined.It is found that even for an overall negative prompt feedback, there exists a limit to the increase in reactor eigenvalue (or in neutron flux), beyond which instability may result. This limit depends on the initial conditions of the perturbed reactor. The neutron flux is shown to be more sensitive to a change ∈ than the reactor eigenvalue, and this sensitivity depends on the temperature variation of feedback. It is also shown that the T-1 variation of the negative Doppler coefficient is more effective than the T-3/2 variation in maintaining reactor stability when the reactor eigenvalue is increased.