AEMO Analysis Found Even Maximum Load Shedding Would Have Left the NEM Short by 800 MW
AEMO's later analysis found 60% demand cuts might still have left 800 MW of unserviceable load as battery storage readies to double across the NEM.
RenewMap data published on Sunday (2026-09-06) put Australia's NEM battery buildout on course for 19.2 GW and 55 GWh, more than double the current 9.5 GW and 21 GWh, with every mainland state set to at least double installed capacity and energy volume in the coming years. The buildout arrives against a grid whose limits AEMO's own retrospective analysis has since quantified: even a complete, timely load shed of 60% of demand during the market's most recent crisis might have left roughly 800 MW of load still in service, more than the surviving generation could absorb.4
That 800 MW figure reflects how little headroom remained in the stack at peak stress. AEMO's chief executive told the Australian Energy Week conference on 11 June (2026-06-11) that the operator had issued around 500 directions to over 5 GW of plant before taking the unprecedented step of suspending the entire National Electricity Market to maintain supply. Nothing at that scale had been attempted before.1
Analysis of what preceded the suspension, published by WattClarity on 28 June (2026-06-28), traced the crisis to very low wind as the initiating condition. With wind largely absent, dispatch leaned hard on gas-fired generation. Transfers from Victoria did not rise consistently enough to fill the gap the wind had left.2
Automated bidding deepened the problem. WattClarity found that most autobidders may not have had the capacity to look beyond AEMO's predispatch price projections, even as real conditions deteriorated faster than those projections showed. The market's self-correcting mechanism stalled at the moment it was most needed.2
Coal would have been the obvious backstop. But nearly 40% of the NEM's coal capacity has retired since market start, leaving an average station age of 38 years, according to the AEMO CEO's June (2026-06-11) remarks. Rooftop solar, at more than 4 million installations and now with aggregate capacity larger than the remaining coal fleet, handles the daytime trough. It contributes nothing after sunset.1
The evening gas buffer is also thin. ITK analysis incorporated into the Sunday (2026-09-06) WattClarity piece put average NEM-wide gas generation at around 2 GW even during the winter evening peak. For a grid that demonstrated it could run 800 MW short despite extraordinary intervention, a 2 GW dispatchable floor is narrow.4
Wholesale prices did not signal the structural tightness. East coast NEM spot prices averaged $74/MWh in Q2 2026, down $66/MWh or 47% from Q2 2025, according to a market review in an August (2026-08-18) JD Supra update covering July 2026 conditions. East coast gas averaged $9.08 per gigajoule in the same period, the lowest since Q2 2021. South Australia's NEM spot was A$71.48/MWh on 7 September (2026-09-07), the one region that had shown any material price volatility across the quarter.3
Queensland wind set a Q2 2026 record, with average generation rising 80% to a new all-time high of 842 MW, the same update showed. Grid-scale batteries were already shifting energy and influencing price formation. But the approaching 55 GWh fleet changes the nature of the problem: ITK estimated the additional battery charging load at around 10 GW at midday, equivalent to a major new demand block pressing on available solar output during the lunchtime trough.3,4
The forward test is duration. A low-wind, high-demand event that runs deep into the evening — the precise combination that preceded the NEM suspension — will ask the battery fleet to discharge through a window the previous 21 GWh system was never tested against. Whether 55 GWh spread across mainland states closes the 800 MW residual gap under those conditions, or merely narrows it, is the number that generation owners bidding the evening peak and retailers managing hedge exposure will be running from different starting assumptions.4,1,2