System Study: High-Pressure Core Spray 1998-2020

Abstract

This report presents an unreliability evaluation of the high-pressure core spray (HPCS) at eight U.S. commercial boiling water reactors. Demand, run hour, and failure data from 1998-2020 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 (ICES). 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 HPCS results. v

NRC Reactor Operating Experience Analysis and Trend Summary: 2020 Update

“…• Loss-of-Offsite-Power (LOOP) Analysis, which is updated annually o Analysis of LOOP Events 2020 Update [1] • Initiating Event (IE) Analysis, which is updated annually o Initiating Event Rates at U.S. Nuclear Power Plants, 2020 Update [2] • Component Performance Studies, which are updated every other year starting with the 2016 update o Enhanced Component Performance Study: Air Operated Valves (AOVs) 1998-2020 [3] o Enhanced Component Performance Study: Emergency Diesel Generators (EDGs) 1998-2020 [4] o Enhanced Component Performance Study: Motor Driven Pumps (MDPs) 1998-2020 [5] o Enhanced Component Performance Study: Motor Operated Valves (MOVs) 1998-2020 [6] o Enhanced Component Performance Study: Turbine Driven Pumps (TDPs) 1998-2020 [7] • System Performance Studies, which are updated every other year starting with the 2016 update o System Study: Auxiliary Feedwater (AFW) 1998-2020 [8] o System Study: Emergency Power System (EPS) 1998-2020 [9] o System Study: High-Pressure Coolant Injection (HPCI) 1998-2020 [10] o System Study: High-Pressure Core Spray (HPCS) 1998-2020 [11] o System Study: High-Pressure Safety Injection (HPSI) 1998-2020 [12] o System Study: Isolation Condenser (ISO) 1998-2020 [13] o System Study: Reactor Core Isolation Cooling (RCIC) 1998-2020 [14] o System Study: Residual Heat Removal (RHR) 1998-2020 [15] • The above analyses may include more specific studies, e.g., the LOOP analysis includes the LOOP IE frequency analysis, LOOP frequency trending analysis, and LOOP duration analysis; the IE analysis includes the IE baseline analysis and IE frequency trending analysis; the industry-average parameter estimates includes component unreliability and initiating event frequency estimates; and the CCF parameter estimates includes estimations of CCF alpha factor, causal alpha factors, and CCF prior distributions. Different periods of data have been selected and used in the specific studies with various reasons, e.g., the most recent 15-year period was generally used in industry-average parameter estimates as well as in the CCF parameter estimates (previously, 1997 or 1998 was mostly used as the starting year for the data period in various analyses including LOOP and parameter estimates) , the most recent 10-year period was usually used in a trending analysis.…”