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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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.
W. W. Little, Jr., R. W. Hardie
Nuclear Science and Engineering | Volume 29 | Number 3 | September 1967 | Pages 402-407
Technical Paper | doi.org/10.13182/NSE67-A17287
Articles are hosted by Taylor and Francis Online.
A description is given of two methods for collapsing many-group cross sections to few-group cross sections. The analysis is applicable to intermediate and large-volume fast reactors. It is shown that the simple flux weighting collapsing recipe—with reciprocal weighting of the transport cross section—is adequate for computing reaction rates, keff, etc., but inadequate for computing moderator reactivity coefficients. A new collapsing algorithm is developed which permits an accurate calculation of moderator reactivity coefficients using few-group cross sections.