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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.
Hugh K. Clark
Nuclear Science and Engineering | Volume 54 | Number 1 | May 1974 | Pages 55-71
Technical Paper | doi.org/10.13182/NSE74-A23393
Articles are hosted by Taylor and Francis Online.
The approximation inherent in using cell-averaged homogenized cross sections in computations for heterogeneous reactors is investigated for slab reactors by discrete integral transport (DIT) theory. Small, but significant, differences in reactivity and anisotropies in migration area are found. The DIT technique is extended to include an exact asymptotic reactor boundary condition and a separable transverse flux. Approximate solutions are investigated in which a reactor is subdivided into a number of zones with the coupling between zones expressed in terms of the directional currents at the interfaces. The sticking probabilities for these currents are derived from Taylor expansions of the source through linear terms. Generally good results are obtained when the zones correspond with the cells in a reactor.