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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
James F. Jackson, William E. Kastenberg
Nuclear Science and Engineering | Volume 42 | Number 3 | December 1970 | Pages 278-294
Technical Paper | doi.org/10.13182/NSE70-A21218
Articles are hosted by Taylor and Francis Online.
A numerical investigation of space-time effects in the dynamic behavior of fast breeder reactors is presented. The basic approach is to compare results from point kinetics and time-dependent diffusion theory. The accuracy of point kinetics is determined for different approximations to the shape function used in calculating the initiating reactivity and feedback coefficients. Several space-dependent feedback models are studied. The importance of considering spatial effects that arise from two sources is shown. The first type consists of those induced by local reactivity perturbations. Usually, these can be adequately accounted for through the proper selection of a shape function. For example, it is found that when calculating rapid, localized ramp insertions, a good choice is the flux shape at prompt critical. The second type consists of those induced by feedback with strong space dependence. Spatial effects of this type are shown to be difficult to cope with when applying point kinetics.