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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.
J. T. Mihalczo, M. V. Mathis, and V. K. Paré
Nuclear Science and Engineering | Volume 59 | Number 4 | April 1976 | Pages 350-368
Technical Paper | doi.org/10.13182/NSE76-A26837
Articles are hosted by Taylor and Francis Online.
An experiment was performed with a mock-up of the core of the Fast Flux Test Facility (FFTF) reactor to evaluate three reactivity measurement methods for application to liquid-metal fast breeder reactors (LMFBR): modified source multiplication measurements with the low-level flux monitor for refueling (∼35 dollars subcritical) of FFTF, noise analysis to 35 dollars subcritical, and inverse kinetics rod drop to ∼12 dollars subcritical. To investigate the spatial dependence of these measurement methods and to resolve discrepancies previously reported, detectors were placed in the core, reflector, and radial shield, and experimental data were collected with the reactivity at near delayed criticality to ∼35 dollars subcritical. Conclusions from this experiment are the following. Low-level flux monitors in the shield of the FFTF will be adequate for reactivity surveillance during refueling, using the modified source multiplication method calibrated near critical by an inverse kinetics rod drop measurement. The break frequency noise analysis method to −35 dollars with in-core detectors, the modified source multiplication method to −35 dollars, and inverse kinetics rod drop method to -12 dollars with detectors at all locations (corrected for changes in nuclear parameters), yielded the same reactivities within <5%. From reactor physics considerations, breakfrequency noise analysis with in-core detectors is best for monitoring reactivity down to full shutdown since it requires only a simple correction with reactivity that depends on global parameters of the system rather than a correction that depends on the value of the flux at a point or on the inherent source intensity, such as are required for the modified source multiplication method. However, for simple point kinetics interpretation of the results, the measurements must be made only with in-core detectors.