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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
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Nuclear Science and Engineering
August 2024
Nuclear Technology
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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
James E. O'Brien, Carl M. Stoots, J. Stephen Herring, Joseph J. Hartvigsen
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 118-131
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3830
Articles are hosted by Taylor and Francis Online.
An experimental program is under way to assess the performance of solid-oxide cells operating in the steam electrolysis mode for hydrogen production in a temperature range from 800 to 900°C. This temperature range is consistent with the planned coolant outlet temperature range of advanced nuclear reactors. Results were obtained from two multiple-cell planar electrolysis stacks with an active area of 64 cm2 per cell. The electrolysis cells are electrolyte-supported, with scandia-stabilized zirconia electrolytes (~140 m thick), nickel-cermet steam/hydrogen electrodes, and manganite oxygen-side electrodes. The metallic interconnect plates are fabricated from ferritic stainless steel. The experiments were performed in a range of steam inlet mole fractions (0.1 to 0.6), gas flow rates (1000 to 4000 standard cubic centimeters per minute), and current densities (0 to 0.38 A/cm2). Steam consumption rates associated with electrolysis were measured directly using inlet and outlet dewpoint instrumentation. Cell operating potentials and cell current were varied using a programmable power supply. Values of area-specific resistance and stack internal temperatures are presented as a function of current density. Initial stack-average area-specific resistance values <1.5 cm2 were observed. Hydrogen production rates in excess of 200 normal liters per hour (NL/h) were demonstrated. Internal stack temperature measurements revealed a net cooling effect for operating voltages between the open-cell potential and the thermal neutral voltage. These temperature measurements agreed very favorably with computational fluid dynamics predictions. A continuous long-duration test was run for 1000 h with a mean hydrogen production rate of 177 NL/h. Some performance degradation was noted during the long test. Stack performance is shown to be dependent on inlet steam flow rate.