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DOE OSTI · 3344454

System Study: Emergency Power System 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 emergency power system (EPS) 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 Industry Reporting and Information System. The unreliability results are trended for the most recent 10 year period while 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 EPS system start-only unreliability, but a statistically significant decreasing trend was identified in the industry-wide estimates of EPS system 24-hour mission unreliability.

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22 GENERAL STUDIES OF NUCLEAR REACTORS99 - GENERAL AND MISCELLANEOUSEmergency Power SystemNuclear Power PlantSystem ReliabilityTrending

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Ma, Zhegang [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000229738557). 2025-12-01. System Study: Emergency Power System 1998-2024. https://doi.org/10.2172/3344454

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