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Nuclear Nonproliferation Policy
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.
Jeng-Ming Fang, Yen-Wan H. Liu, Horng-Kuang Liu, Pin-Wu Kao, Jing-Tong Yang
Nuclear Science and Engineering | Volume 116 | Number 3 | March 1994 | Pages 181-204
Technical Paper | doi.org/10.13182/NSE94-A19812
Articles are hosted by Taylor and Francis Online.
A two-dimensional perturbation method with regionwise flux expansion is developed and tested for the boiling water reactor fast shutdown margin calculation. The ways of generating the two-dimensional parameters for the unrodded bundles are tested to find the one that results in the most accurate eigenvalue of the single-rod-out condition. The use of the one-bundle-per-region flux expansion method gives more accurate results than the ring-regionwise flux expansion method. The first four strongest control rods chosen by this method using one-bundle-per-region flux expansion always contain the top four strongest rods predicted by SIMULATE-3 three-dimensional calculations. The strongest rod is always correctly predicted, and the differences in shutdown margin predictions are <1 mk for all the cases tested. The time saved by using the two-dimensional perturbation method rather than the direct three-dimensional full-core calculation is a factor of ∼10 and even more for larger core loadings. By using correct two-dimensional parameters, the accuracies of the perturbation method itself in the calculations of the eigenvalue and the neutron flux distribution are also tested. It is found that the errors are very small even for such a strong perturbation in the shutdown margin calculation.