VIC1 experienced sustained negative pricing during the early morning of 3 September 2026, with prices reaching −$7.62/MWh at 04:45 and −$6.00/MWh at 04:50. The event spanned two intervals with an average minimum price of approximately −$8/MWh, occurring during a period of high renewable generation (wind and solar totalling over 6,500 MW) combined with inflexible brown coal baseload output.
The negative pricing was driven by over-supply conditions characterised by high renewable generation meeting low demand in the pre-dawn period, with brown coal generation (2,410 MW) unable to rapidly ramp down. A binding constraint with marginal value of $1,002.29 (F_T+RREG_0050) indicates significant operational constraints on regulation, which likely restricted the market's ability to manage excess supply through conventional flexibility mechanisms, forcing the price mechanism to incentivise demand and/or generation withdrawal.
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.