VIC1 experienced sustained negative pricing at −$0.05/MWh across two consecutive intervals (13:00–13:05 on 18 August 2026), representing a minor but notable market event. Prices had declined sharply from $10.50/MWh approximately 25 minutes earlier, touching near-zero and then briefly negative levels.
The negative pricing occurred during a period of very high wind generation (approximately 3,470 MW average across VIC1) combined with significant baseload brown coal output (2,783 MW), creating structural oversupply. The binding constraint F_T+LREG_0050 displayed declining marginal values (from $26.92 to $13.85/MWh) across the price collapse period, indicating constraint-driven dispatch economics were tightening; however, the high renewable output and inflexible thermal generation base appear to be the primary drivers of the supply surplus that forced prices negative when demand could not absorb available capacity.
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.