Victoria (VIC1) experienced sustained negative pricing during two consecutive intervals on 31 May 2026 (00:10–00:15), with prices reaching −$0.10/MWh. This followed a period of near-zero pricing around midnight, reflecting oversupply conditions in the region during low-demand evening hours.
High renewable generation—particularly wind at approximately 4,984 MW combined and solar at 400 MW—combined with inflexible brown coal baseload (3,019 MW) created a structural oversupply when demand was minimal in the late evening. The binding Tasmanian and Interconnector constraints (F_TASCAP_RREG_0220, F_T+RREG_0050, F_I+RREG_0220) restricted exports and power flow management options, preventing VIC1 from efficiently exporting excess generation and forcing the region into negative pricing to incentivise consumption and manage the surplus.
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.