VIC1 experienced sustained negative pricing of −$0.55/MWh across two consecutive intervals (14:10 and 14:15 on 12 September 2026), following a period of near-zero pricing. The generation mix during this period was dominated by wind (combined ~6,410 MW) and brown coal (~2,554 MW), with minimal contribution from flexible generation sources.
The negative pricing reflects a supply–demand imbalance where generation substantially exceeded controllable demand absorption capacity. The high marginal values ($10.68–$11.26/MWh) associated with the binding constraint F_T+LREG_0050 indicate that a specific transmission or network constraint was actively limiting the market's ability to export or redistribute excess generation, forcing the dispatch of excess wind generation at negative prices to maintain system stability. With gas and solar generation offline and battery output negligible, VIC1 lacked dispatchable capacity to modulate supply, amplifying downward price pressure during the high wind generation window.
Causal analysis generated by gridIQ's synthesis model from live AEMO market data: dispatch prices, generation mix, interconnector flows and market notices in the interval surrounding the event.