VIC1 experienced two intervals of negative pricing at -$2.42/MWh on 19 August 2026 at 04:10 and 04:20, representing a minor severity event amid otherwise moderately positive prices. The negative prices occurred within a generation environment dominated by wind (6,961.62 MW combined) and brown coal (3,667.97 MW), with minimal gas generation online.
The negative pricing reflects an oversupply condition typical of high wind generation periods during off-peak hours when demand is low. Binding constraints with significant marginal values—particularly F_S++HYSE_R60 ($25 and $19.95/MWh) and F_T+RREG_0050 ($5.26/MWh)—indicate network flow limitations that restricted the ability to export excess generation, forcing the market price down to incentivise load acceptance and reduce output. The rapid price recovery to $35.87/MWh in the preceding interval and subsequent volatility suggest dispatch management responding to these constraint-binding conditions.
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.