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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.
P. Reuss
Nuclear Science and Engineering | Volume 92 | Number 2 | February 1986 | Pages 261-266
Technical Paper | doi.org/10.13182/NSE86-A18174
Articles are hosted by Taylor and Francis Online.
Because of the large number of heavy nuclide resonances, a detailed neutron flux calculation in the epithermal range cannot be made by standard nuclear reactor codes: It would need several tens of thousands of energy points. However, by using precalculated effective reaction rates, only a few tens of groups are sufficient for accurate spectrum and reaction rate calculations, if a consistent formalism is used. Such a formalism was elaborated in the 1970s by M. Livolant, F. Jeanpierre for the “one resonant nuclide-one resonant zone” problem, and was implemented in the APOLLO code. In practical cases there are several resonant nuclides and often resonant zones of different characteristics, e.g., a lattice constituted with different kinds of pins, a lattice with irregular “water holes,” a fuel element with temperature (therefore Doppler effect) gradients, and so on. Since these problems cannot be correctly treated by APOLLO, a generalization of the formalism was derived. The basic principles were retained, and an algorithm was constructed that would not require too expensive calculations. The Livolant-Jeanpierre theory is briefly summarized, equations for the most general case are presented, some approximations for practical calculations are proposed, and numerical tests on significant examples are discussed.