VIC1 experienced sustained negative pricing at approximately -$2/MWh across multiple consecutive intervals on 1 June 2026 from 16:40 to 17:10, with the minimum price reaching -$2.26/MWh. This minor severity event reflects a temporary oversupply condition in the Victorian electricity market during the late afternoon period.
The negative pricing was primarily driven by exceptionally high wind generation (approximately 6,275 MW combined from multiple wind sources) combined with continued brown coal output (3,066 MW), creating significant excess supply that could not be readily absorbed or curtailed. The binding transmission constraints from Tasmania (F_TASCAP_RREG_0220 and F_T+RREG_0050) with marginal values around $6-7/MWh indicate that network limitations prevented efficient export of surplus energy, forcing the market to pay participants to reduce generation, resulting in negative prices as the cost of backing down inflexible coal generation exceeded the opportunity cost of wind.
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.