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2024 ANS Winter Conference and Expo
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Orlando, FL|Renaissance Orlando at SeaWorld
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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. E. Cockayne, K. O. Ott
Nuclear Science and Engineering | Volume 43 | Number 2 | February 1971 | Pages 159-172
Technical Paper | doi.org/10.13182/NSE71-A21264
Articles are hosted by Taylor and Francis Online.
A new zero-dimensional procedure was developed for the calculation of neutron spectra in a fast reactor. The procedure yields a good approximation to the spectrum at a given “point” in a fast reactor rather than for a larger “region.” Therefore, the procedure is especially suitable for the calculation of spectra in transition areas where other methods are very inaccurate. These close approximations to actually occurring spectra have been found to be good trial functions for the space-energy synthesis method of approximately solving the multigroup equations. The new procedure is based on an approximate flux from a 2-mode synthesis solution; high accuracy is not required for this initial flux. A single-group diffusion kernel is applied as weight function in the derivation of the zero-dimensional multigroup equations for the spectrum at a given point. Application of this procedure for two or more points yields an excellent set of trial functions for a subsequent space-energy synthesis calculation. Normally, M modes (with M > 2) are used in the second synthesis calculation. The complete synthesis procedure is therefore called “successive 2-M mode space-energy synthesis.” Application of a successive 2–3 mode synthesis to a two-region fast reactor model yielded very high accuracy when compared with a numerical multigroup (diffusion) reference solution. Two substantially different 2-mode solutions used as basis for the calculation of the new set of trial spectra gave approximately the same final accuracy. The high accuracy and the small computation time give the successive synthesis method a good chance to compete with the multigroup method either by a reduction in computation time or by an increase in accuracy through a more detailed description of the energy dependence.