Daily Aggregation of Network Outages on the Western Power Network January 2003 to July 2026

This is the aggregated summery of the outages on the Western Power Network (scroll down the page to “network coverage" on the Western Power website for an overview). In this context, an “outage” is a complete loss of supply to one or more properties that lasts longer than one minute. Columns B to E are for any interruption regardless of cause or circumstance that started during the date in question, irrespective of if the outage continued into the proceeding date(s). A Major Event Day is a quantifiable definition of when we have an “extraordinary event” Colum F, as described would not apply to every interruption during that day (eg and outages from car hitting poles when in Albany when there was storm activity in Perth). The definitions of SAIDI, CAIDI, Major Event Days, and other related reliability metrics are based on the IEEE Guide for Electric Power Distribution Reliability Indices (IEEE Std 1366). However, Western Power, along with other Australian distribution network service providers, has adapted the methodology used to determine the Major Event Day threshold to better reflect local operating conditions and specific network circumstances.