Australia’s Coal Plants Chalked up 108 Outages over Summer – 90 of Them Unplanned

Why It Matters

The outage surge exposes coal’s operational fragility, accelerating the shift toward cleaner, more dependable generation and pressuring policymakers to fast‑track decarbonisation.

Key Takeaways

• 108 coal outages, 90 unplanned, summer 2025‑26.
• Average 25% coal capacity offline, ~5.3 GW.
• Maintenance overruns added ~2 weeks per unit.
• Renewables supplied ~50% NEM summer electricity.
• Frequent outages raise wholesale prices, risk supply shortages.

Pulse Analysis

Reliability Watch’s latest report paints a stark picture of Australia’s coal fleet during the 2025‑26 summer. Over five months, 108 outages were logged across 15 coal stations, with unplanned incidents accounting for 83% of events. Capacity availability slipped to an average of 25% offline, translating to more than 5 GW of lost generation. Even scheduled maintenance proved problematic, with units like Yallourn 2 and Tarong 1 extending twice beyond their planned downtime. These figures contrast sharply with earlier periods, highlighting a growing trend of operational strain as plants age.

The reliability crisis is reverberating through the wholesale market. With half of the NEM’s summer supply now coming from solar, wind and battery storage, the system has partially insulated itself from price spikes, yet the lingering coal shortfalls keep price volatility elevated. Consumers face higher bills as generators hedge against supply uncertainty, and network operators must balance intermittent renewables with the unpredictable output of aging coal units. The data underscores the economic incentive for accelerated investment in dispatchable renewable resources and grid‑scale storage, which can provide the firm capacity traditionally supplied by coal.

Policy makers and regulators are now confronted with concrete evidence that coal can no longer be counted on for baseload reliability. The persistent outages and maintenance overruns strengthen the case for a structured coal phase‑out timetable aligned with Australia’s net‑zero commitments. Incentives for fast‑track solar‑plus‑storage projects, streamlined permitting for new wind farms, and clear market signals for firm capacity will be essential to replace the dwindling coal contribution. As the transition gains momentum, the NEM’s resilience will increasingly depend on a diversified generation mix rather than legacy fossil assets.