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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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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Keeping up with Kewaunee
In October 2012, Dominion Energy announced it was closing the Kewaunee nuclear power plant, a two-loop 574-MWe pressurized water reactor located about 27 miles southeast of Green Bay, Wis., on the western shore of Lake Michigan. At the time, Dominion said the plant was running well, but that low wholesale electricity prices in the region made it uneconomical to continue operation of the single-unit merchant power plant.
Arthur H. Jaffey
Nuclear Science and Engineering | Volume 1 | Number 3 | July 1956 | Pages 204-215
Technical Paper | doi.org/10.13182/NSE56-A17852
Articles are hosted by Taylor and Francis Online.
The neutron economy of a thermal reactor or system of reactors using Pu239 as fuel for long time periods is examined. In the first case treated, only the change in neutron absorption and production due to plutonium isotope growth is considered. In the second, and more complete case, the effect of neutron absorption by fission products is included. Both analyses are developed in terms of an idealized system in which: (1) a uniform and constant flux of 3 × 1014 neutrons/cm2/sec is assumed; (2) the Pu239 level is kept constant by internal regeneration or from external sources; (3) neutron escape and neutron capture by structure, moderator, and coolant are neglected; (4) excess neutrons beyond those needed to propagate the chain are absorbed in the fertile material, U238, to regenerate Pu239; and (5) contributions to the neutron economy from U238 and U235 fission are not included. In the first case (omitting fission product absorption), the system is found to be approximately regenerative, i.e., at equilibrium, about as much Pu239 is formed as is destroyed. In the second case (including fission products), the regenerative properties become relatively poor unless fission products are removed periodically. A particular processing cycle is examined, in which chemical separations occur at 0.2-year intervals (nvt — 2 × 1021 neutrons/cm2) and is found to yield an almost regenerative system, so that relatively little Pu239 has to be supplied from external sources.