VIC1 experienced sustained negative pricing at −$0.05/MWh across two consecutive intervals (02:00 and 02:05 on 12 August 2026), following a sharp price decline from $6.42 to near-zero levels. The event occurred during a period of high renewable generation (3171 MW wind, 396 MW solar) and high brown coal output (2845 MW), creating significant supply-demand imbalance.
The negative pricing was driven by a binding constraint (NSA_Q_GSTONE34_250) with a substantial marginal value of approximately $23,160/MWh, indicating that the constraint was severely limiting dispatch options and forcing the market to accept negative prices to manage excess generation. The high renewable output combined with inflexible brown coal baseload generation created a situation where supply substantially exceeded demand during the early morning period, and the active constraint prevented efficient re-dispatch, necessitating negative pricing as the only available market mechanism.
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.