VIC1 experienced sustained negative pricing at $-1.10/MWh during the 05:00 settlement interval on 24 July 2026, with a second negative interval at $-0.02/MWh five minutes later. The event occurred during early morning low-demand conditions with high wind generation (3407–3477 MW) and brown coal output (3409 MW) creating a structural oversupply situation.
The negative pricing was driven by excess renewable and coal generation during a period of minimal demand flexibility, with no battery storage or gas generation available to absorb the surplus supply. Multiple binding constraints with significant marginal values—including renewable regulation constraints and a Tasmania capacity constraint—indicate that system stability requirements and inter-regional transmission limitations prevented efficient redistribution of the excess generation, forcing prices negative to incentivise demand participation and generation reduction.
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.