VIC1 experienced brief periods of negative pricing on 11 August 2026 around 16:30–16:50, with the minimum spot price reaching –$0.10/MWh across two intervals. The region saw elevated wind generation (approximately 4,000–4,100 MW) combined with significant brown coal output (2,906 MW), creating an oversupply condition.
The negative pricing was driven by a combination of high renewable generation and constrained system flexibility. With binding constraint F_T+LREG_0050 active at high marginal values (around $88.62–$88.72/MWh), the system faced a binding operational constraint that limited the ability to manage the excess supply from wind generation. The absence of solar contribution and minimal battery charging, coupled with inflexible coal baseload, left insufficient demand-side flexibility or dispatchable reserve capacity to absorb the wind surplus, forcing prices into negative territory as generators were paid to reduce output.
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.