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Division Spotlight
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.
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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Latest News
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.
P. Greebler
Nuclear Science and Engineering | Volume 3 | Number 4 | April 1958 | Pages 445-455
Technical Paper | doi.org/10.13182/NSE58-A25481
Articles are hosted by Taylor and Francis Online.
Thermal and epithermal absorption of neutrons by a cylindrical control rod are computed using two-group diffusion theory and assuming a flat source distribution for the epithermal group. Hurwitz-Roe area rule concepts are modified to take into account the nonthermal absorption by the rod and are extended to include rods that are not “black.” The effect of the control rod on the neutron economy is averaged over a cylindrical cell surrounding the rod and is expressed in terms of two-group absorption cross sections. Control rod power perturbations in a reactor are calculated from the two-group flux distributions in the cell containing the centered control rod.
