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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
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.
V. Drüke, D. Filges, R. D. Neef, N. Paul, H. Schaal
Nuclear Science and Engineering | Volume 97 | Number 1 | September 1987 | Pages 37-52
Technical Paper | doi.org/10.13182/NSE87-A23494
Articles are hosted by Taylor and Francis Online.
Several fuel-loading concepts are proposed for high-temperature reactors of the pebble-bed type. A very promising one is the so-called OTTO (once through then out) loading scheme. Some of the intrinsic features of OTTO fuel loading are the axial nonsymmetrical power and neutron flux distribution with a pronounced maximum at the upper reactor core region. Since the neutron physics of OTTO cores will be very different from previous homogeneous fuel-loading schemes, detailed experimental and theoretical investigations of these objectives were performed at the critical facility KAHTER. Experimental and theoretical investigations have been carried out to determine critical masses, reaction rates, and control rod worths in the upper cavity and top reflector. Fast flux distributions in upper graphite reflectors were also measured to estimate graphite damage. The critical masses and keff’s are calculated using two- and three-dimensional code systems. The three-dimensional codes give keff values for the high-temperature gas-cooled reactor OTTO cores at zero burnup within a margin that is currently standard for these calculations. The agreement of measured and calculated reactivity worths of the top reflector rods is better than 2%.