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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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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.
Charles R. Marotta
Nuclear Science and Engineering | Volume 77 | Number 1 | January 1981 | Pages 107-109
Technical Note | doi.org/10.13182/NSE81-A21343
Articles are hosted by Taylor and Francis Online.
The algebraic difference between the average neutron lifetime (l) and the average generation time (g), referred to as the excess time E (= l − g), is shown to be a useful parameter giving physical insight into the degree of utilization of neutrons toward a chain reacting process in a complicated fissionable system. It can be used to support physical arguments in checking the validity of complex computer results as well as to give some rationale as to what results to expect in these calculations. The concept is applied to the classic criticality case of dry or wet storage of separated fuel assemblies in a variable density hydrogenous moderator.