SNUPPS is an acronym standing for Standardized Nuclear Unit Power Plant System. It refers to a 4-loop PWR reactor design produced by Westinghouse in the 1970s. The design was developed for 4 USA utilities, and plants were built at Callaway and Wolf Creek. The UK plant at Sizewell B was also based on SNUPPS but with significant modifications, such as a passive Emergency Boration System.
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SNUPPS Wikipedia(Text) CC BY-SA