Measuring Electricity Network Resilience in Australia: A Statistical Analysis of Current Regulatory and Extreme-Event Data

Purpose: Australian electricity networks face growing exposure to extreme weather, including catastrophic bushfires, tropical cyclones, and severe storms, that stresses the National Electricity Market (NEM) well beyond the scope of conventional reliability regulation. This paper examines how electricity network resilience is, and might better be, measured in Australia. It distinguishes resilience from routine reliability, as captured by the System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI).Approach: Applies a statistical analysis to the latest data published by the Australian Energy Regulator (AER) and Australian Energy Market Operator (AEMO). Using 2024 national distribution network data, the analysis quantifies a reliability–resilience gap of approximately 70.8 percent of total outage minutes and 37.5 percent of total interruptions that fall outside normalized reliability reporting. Case analyses of the 2019–20 Black Summer bushfires and the March 2025 Ex-Tropical Cyclone Alfred, Queensland's largest natural-disaster outage event on record, illustrate the scale of extreme-event impact. The paper further examines the Australian Energy Market Commission's May 2025 rule change embedding a formal distribution network resilience framework in the National Electricity Rules, together with cost pass-through data and Victorian resilience capital expenditure, as emerging indicators of a nationally consistent resilience metric.Findings: The findings indicate that Australia's reliability-incentive architecture, while effective for routine performance, systematically understates the customer-facing burden of extreme events, and that new regulatory reforms are beginning to close this measurement gap.