Washington Utilities and Transportation Commission
Regulated electric utilities must file reliability reports at least once a year. The report must identify the total number of customer complaints about reliability and power quality made to the utility during the year, and must distinguish between complaints about sustained interruptions and power quality. The report must also identify complaints that were made about major events.
Washington's three investor-owned electric companies use two main metrics, SAIDI and SAIFI, to describe the reliability of the service they provide. SAIDI, the System Average Interruption Duration Index, describes the average length of an outage in minutes. SAIFI, the System Average Interruption Frequency Index, describes the average number of outages a customer experiences.
The following data comes from annual reports filed by each regulated utility.
For the current report click on the total in the last column.
National Regulatory Research Institute (NRRI) Reports
UTC Study on System Cost Data submitted by Regulated Industries
Department of Commerce Study on System Reliability