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The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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.
H. van Dam
Nuclear Science and Engineering | Volume 129 | Number 3 | July 1998 | Pages 273-282
Technical Paper | doi.org/10.13182/NSE98-A1981
Articles are hosted by Taylor and Francis Online.
An analysis is presented of reactor dynamics during inherent shutdown and recriticality after loss of cooling without scram. The influence of the strength of external neutron sources is studied, and the dynamics of fission product decay heat is explicitly taken into account. It is shown that decay heat and (in thermal reactors) xenon dynamics play a dominant role in inherent reactor shutdown. Fission power level at first spontaneous recriticality is determined by both the strength of the external/inherent neutron sources and the reactivity ramp rate induced by xenon decay and cooling down of the subcritical reactor core. The first power surge after recriticality is only very weakly dependent on the external/inherent neutron source strength, and the amplitude of fission power oscillations is mainly determined by the reactivity ramp rate at first recriticality. Frequency and stability of the power oscillations after recriticality depend on the thermal inertia of the core and the power-reactivity defect. Stability is slightly deteriorated by the fission product decay dynamics, but the influence of xenon dynamics is negligible.