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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.
J. D. Jenkins, P. B. Daitch
Nuclear Science and Engineering | Volume 31 | Number 2 | February 1968 | Pages 222-233
Technical Paper | doi.org/10.13182/NSE68-A18234
Articles are hosted by Taylor and Francis Online.
A simple model is developed to describe the time-dependent neutron spectrum in pulsed systems whose decay may be dominated by either a fundamental or a pseudofundamental mode. Such systems include a large class of fast multiplying assemblies and thermal nonmultiplying assemblies. The simple model provides qualitative understanding of the role played by the fundamental or pseudofundamental mode in the kinetic evolution of the time-dependent neutron flux and, when optimized by a variational principle, gives excellent quantitative descriptions of the flux for a wide range of systems. Trial functions are presented which, when adjusted with a suitable variational principle, provide a good estimate of the shape and decay rate of the dominant reproducing mode of such systems. The method works well for systems where a fundamental mode exists and is also applicable in the range where pseudofundamental mode behavior is observed. Eigenfunction eigenvalue solutions are obtained for the fast multiplying system GODIVA and these, together with similar solutions for beryllium, provide a basis of comparison for the variational methods. The investigation shows that care should be exercised in associating reactivity and period parameters with far subcritical systems because the flux shape is changing substantially and the major regenerative mode is not isolated when the eigenvalue associated with this mode lies in the continuum. In the farther subcritical region an example shows a complete lack of a single dominant mode.