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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
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.
Hiroshi Motoda
Nuclear Science and Engineering | Volume 41 | Number 1 | July 1970 | Pages 1-13
Technical Paper | doi.org/10.13182/NSE70-A20357
Articles are hosted by Taylor and Francis Online.
A variational treatment of the burnup optimization of continuous scattered refueling is presented and numerical solutions are given for a slab reactor. It is made quantitatively clear how the reactor dimension, the xenon and the Doppler feedback reactivity, the burnup dependence of fission cross section and the reflector performance affect the power distribution that maximizes the average discharge exposure. Power flattening and burnup maximization are contradictory in general, but are consistent if, and only if, the condition of the perfect reflection at the core boundary is satisfied. The optimal power distribution is peaked in the central—and depleted in the outer region; and becomes flatter as the reflector performance is increased. The maximum average burnup depends on the burnup dependence of fission cross section and the strength of the Doppler and the xenon feedback reactivity, even if the average burnup calculated by the point-reactor model is the same. The former effect on the optimal power distribution is very small but the latter effects greatly contribute to power flattening. Both effects reduce the maximum burnup and the effects of the latter two are of comparable order. As the reactor becomes smaller, the maximum burnup decreases almost linearly to the neutron leakage. Optimal refueling has an advantage of more than 10% in the average burnup over the conventional flat-refueling rate method. However the difference from the flat-burnup method is very small, considering that the optimal refueling is handicapped by its very bad power distribution.