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DOE OSTI · 3376014

System Study: Residual Heat Removal 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 residual heat removal (RHR) system in two modes of operation (low-pressure injection in response to a large loss-of-coolant accident and in response to post-trip shutdown cooling) at 93 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 1998 to 2024 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Industry Reporting and Information System (IRIS), formerly the INPO Consolidated Events Database. 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. Statistically significant and highly statistically significant decreasing trends were observed for RHR low-pressure injection mode start-only unreliability and RHR low-pressure injection model 24-hour unreliability.

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22 GENERAL STUDIES OF NUCLEAR REACTORS42 ENGINEERING99 - GENERAL AND MISCELLANEOUSNuclear Power PlantResidual Heat RemovalSystem ReliabilityTrending

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Ma, Zhegang [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000229738557). 2026-02-26. System Study: Residual Heat Removal 1998-2024. https://doi.org/10.2172/3376014

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