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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
W. G. Winn, P. B. Parks, N. P. Baumann, C. E. Jewell
Nuclear Science and Engineering | Volume 65 | Number 2 | February 1978 | Pages 254-272
Technical Paper | doi.org/10.13182/NSE78-A27155
Articles are hosted by Taylor and Francis Online.
Unsymmetric perturbations were introduced into the core of a large, critical, heavy-water-moderated, multiregional reactor. The resulting three-dimensional changes in flux level and shape with time were measured. Perturbations included: 1. Free-fall insertion of rods near the reactor center. Each rod contained 235U slugs in the bottom half and lithium slugs in the top half 2. Free-fall insertion of rods into an off-center radial position. Each rod contained 235U slugs in the bottom half and aluminum in the top half. 3. Withdrawal of cadmium control rods from the central 20% of the reactor core. Flux tilts calculated with the TRIMHX code were within 5% of measured flux tilts. TRIMHX provides a three-dimensional (hex-z geometry) solution of the few-group neutron diffusion and delayed precursor equations without feedback. Inputs to the calculations are available in sufficient detail to allow other methods of solution to be tested.