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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.
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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.
S. K. Bhattacharyya, R. B. Pond
Nuclear Science and Engineering | Volume 65 | Number 3 | March 1978 | Pages 548-553
Technical Note | doi.org/10.13182/NSE78-A27186
Articles are hosted by Taylor and Francis Online.
The Doppler effect of a small UO2 sample was determined for the temperature range from 300 to 1100 K at the core center of the Argonne National Laboratory gas-cooled fast reactor (GCFR) critical assembly. The measurement provided the first data on the important 238U Doppler effect in GCFR systems. The normalized value of the GCFR 238U Doppler effect was found to be 54% smaller than the corresponding value in an equivalent liquid-metal fast breeder reactor (LMFBR) assembly. Calculations with ENDF/B-IV data yielded a calculated/experimental (C/E) ratio of 0.83, which is considerably lower than that in LMFBR assemblies. The reason for this misprediction appears to be an underprediction of the low-energy flux, a feature that seems to be general to hard spectrum assemblies. The 238U Doppler effect was also determined in a “steam-flooded” GCFR assembly. The Doppler effect for the temperature range from 300 to 1100 K increased by 93% relative to the “dry” reference value because of spectral softening. The same calculational methods using ENDF/B-IV data resulted in the much better C/E value of 1.00.