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Division Spotlight
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.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Brenden Heidrich, Samuel A. Oyewole, Richard Olawoyin
Nuclear Technology | Volume 182 | Number 1 | April 2013 | Pages 13-25
Technical Paper | Fission Reactors/Nuclear Plant Operations and Control | doi.org/10.13182/NT13-A15822
Articles are hosted by Taylor and Francis Online.
Currently operating U.S. nuclear power plants operate efficiently and provide base-load electricity at low cost. The nuclear industry relies on total annual power output (availability) as a measure of success, while the government regulator uses the rate of plant failures (reliability) as an indicator of safety, which is the more important performance metric from their point of view. This paper investigates the effects of extending the operating power of U.S. boiling water reactors (BWRs) on reliability as measured by the frequency of licensing event report submission by the plants under study. The possibility of selection bias was investigated by comparing the reliability of BWRs that did not perform an extended power uprate with the behavior of BWRs that would uprate in the future. The control plants exhibited higher reliability in the period 1990 to 2011 than the preextended power uprate plants [mean time between failures (MTBF) 49.1 versus 34.3 p = 0.009]. Finally, the reliability of the plants was investigated before and after the uprates. Since large power uprates are a relatively recent phenomenon, there is much less data available for the post extended power uprate (EPU) period. This has the effect of enlarging the confidence intervals around the MTBF estimates. The beta parameter (slope of the cumulative failure rate) is used to compare the pre- and post-EPU periods. The analysis shows that the reliability of the tested BWRs improved following the implementation of large power uprates ( 0.63 versus 0.56 p = 0.043). This result shows that the effect of replacing and refurbishing plant equipment as part of the power uprate is larger than the effect of the higher power on the plant reliability.
