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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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.
V. K. Paré, J. T. Mihalczo
Nuclear Science and Engineering | Volume 56 | Number 2 | February 1975 | Pages 213-218
Technical Note | doi.org/10.13182/NSE75-A26662
Articles are hosted by Taylor and Francis Online.
A theory is developed for the cross-power spectral densities between the signal from an ionization chamber containing a 252Cf neutron source, which provides the initiation of fission chains in a reactor or neutron multiplying assembly, and the signals from detectors of particles from fission chains in the reactor. Previously derived spectral densities between two detectors are modified to include the effects of the inherent and 252Cf source in the reactor. Calculations of the amplitude of the coherence function for noise measurements, both conventional and 252Cf, for the reactor at the Fast Flux Test Facility are presented and can be used to estimate the time required for a measurement with a given precision. The equivalence between the expressions developed here and those previously developed for time-domain measurements of this type is also shown. Use of a 252Cf chamber makes possible a new method of determination of the reactivity which is independent of the inherent source strength and detection efficiency. This method does not require a calibration near delayed criticality as do the previously used methods such as break frequency or coherence amplitude noise analysis and modified source multiplication measurements. It requires the knowledge of some properties of the ionization chamber containing 252Cf which can be determined outside the reactor. Since this method does not require a calibration near delayed criticality, it may be used in the initial loading of a reactor to determine the reactivity before criticality is achieved. The independence of detection efficiency also makes it useful during initial loading, since large changes in detection efficiency can occur with loading. The independence of the method on the inherent source would be advantageous during refueling of a reactor when the inherent source in the fresh fuel inserted may be much less than that of the burnt-up fuel removed. The method may also be useful in determining the reactivity of assemblies where sufficient fuel to achieve criticality is not available.
