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Westinghouse 3-loop PWRs

  1. Aug 23, 2011 #1
    Would anybody happen to have at hand the water volume of the secondary side of Westinghouse 3 loop PWR steam generators?

    Regarding the loss of external grid incident at North Anna, it would be nice to have a rough estimate of how long the plants could survive a total blackout by boiling off water from the SG:s.
  2. jcsd
  3. Aug 23, 2011 #2


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    Earthquake was about 8-9 miles from the plant, although some info indicates 1 mile. They lost off-site power and the EDGs started up. Both units shutdown.

    I'm sure they'll have an interesting Event Report out soon.
  4. Aug 23, 2011 #3


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    With a loss of feedwater flow, PWR steam generators boil dry in minutes.

    North Anna has a terry turbine (steam-powered pump) to provide feedwater flow in the case of loss of total electrical power failure, as well as a station blackout diesel (in addition to the regular backup diesels).
  5. Aug 24, 2011 #4
    If the steam generators are similar to Ringhals 4, which is a 935 MWe Westinghouse 3-loop PWR, their secondary side inventory would appear to be some 40 m3 or 30 t per SG, which would 1 hour after scram be enough for approximately 1.5 h, if I got the figures correct.

    However, the existence of a steam driven auxiliary pump and an SBO diesel make the situation appear quite non-problematic.
    Last edited: Aug 24, 2011
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