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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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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. J. McCool, R. A. Robinson, E. W. Schrader, S. H. Weiss
Nuclear Science and Engineering | Volume 9 | Number 1 | January 1961 | Pages 47-54
Technical Paper | doi.org/10.13182/NSE61-A25864
Articles are hosted by Taylor and Francis Online.
The cold, clean, steel-reflected, final, SM-2 mock-up containing 36.4 kg U235 and 61 g B10 maintained criticality after a seven rod bank withdrawal of 6.974 in. and has an “excess K” (ΔKE) of 1520 cents. An infinite steel-water laminated reflector is worth approximately +85 cents over the infinite water reflected core. The measured reactivity coefficient, @ 2000 psi, ranges from –1.15 cents/°F @ 150°F to –5.20 cents/°F @ 510°F. The integral reactivity effect of raising the SM-2 core water temperature from 103 to 510°F @ 2000 psi and the water in the reflector coolant graph from 103 to 477°F @ 2000 psi is –889.7 cents. The average measured material coefficients for U235 and B10 are 0.157 cents/g and 42.54 cents/g, respectively. Without the benefit of flux suppressors the maximum to average power ratio of 7.28 occurs at the top of the fuel section of control rod C (withdrawn to 7.14 in.), and a ratio of 5.28 occurs at the bottom of stationary element 43 and symmetric elements.