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DOE OSTI · 3376013

System Study: Auxiliary Feedwater 1998-2024

Ma, Zhegang [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000229738557)
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Abstract

This report presents an unreliability evaluation of the auxiliary feedwater (AFW) system at 62 U.S. commercial operating nuclear reactors. New Standardized Plant Analysis Risk (SPAR) models with the most recent SPAR parameter update results were used in this report. Demand, run hour, and failure data from calendar years 1998 to 2024 for selected components were obtained from the Institute of Nuclear Power Operations Industry Reporting and Information System. The unreliability results are trended for the most recent 10 year period and yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the industry-wide estimates of AFW system start-only unreliability, but a statistically significant decreasing trend was identified in the industry-wide estimates of AFW system 24-hour mission unreliability.

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22 GENERAL STUDIES OF NUCLEAR REACTORS42 ENGINEERING99 - GENERAL AND MISCELLANEOUSAuxiliary FeedwaterNuclear Power PlantSystem ReliabilityTrending

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Ma, Zhegang [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000229738557). 2026-02-26. System Study: Auxiliary Feedwater 1998-2024. https://doi.org/10.2172/3376013

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