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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.
G. E. Hansen and H. A. Sandmeier
Nuclear Science and Engineering | Volume 22 | Number 3 | July 1965 | Pages 315-320
Technical Paper | doi.org/10.13182/NSE65-A20935
Articles are hosted by Taylor and Francis Online.
Adjoint transport theory is most widely used in perturbation theory. A most common problem here is the determination of the reactivity change in a self-multiplying system due to the insertion of an absorber in a small region. There is, however, a class of problems of the source-detector type where adjoint transport theory proves to be a very effective and fast way of obtaining the desired results. In many practical source problems we want to evaluate the reaction rate, say fissions or absorptions, in a material surrounded by a moderator due to a neutron flux incident on the assembly. Here the main advantage of using the adjoint method as opposed to the conventional real-flux shell-source calculations is a significant reduction in computer time. The reactions induced by each group of source neutrons is obtained from one run of an adjoint problem. To obtain the same information from real-flux calculations we need an individual run for every energy group g. Computer time savings ranging by a factor of 5 to 30 are representative. The theory previously reported by one of us (H.A.S.) in the classified literature is derived and subsequently applied to the following problems. a. the fissions induced in a spherical plutonium-detector foil separated by a moderating layer from an incident collimated neutron beam; b. a neutron-dose-rate detector device consisting of a lithium iodide crystal to register absorptions surrounded by a sphere of polyethylene; c. the theoretical evaluation of the neutronic coupling coefficient between two reactors, as one might visualize in a clustered-Rover nuclear-reactor rocket-engine system.