VIC1 experienced negative pricing in two intervals during the early morning of 31 August 2026, with the minimum price reaching -$3.64/MWh at 03:35. The event occurred during a period of high solar generation (1,235.59 MW) and substantial battery output (167.81 MW), coinciding with low system demand typical of the overnight period.
The sustained negative pricing appears driven by an excess of low-marginal-cost renewable generation overwhelming near-minimum system demand. A binding constraint (F_T+RREG_0050) with marginal values around $4.38–$4.39/MWh was active during the period, suggesting a transmission or regional regulation limitation forced the dispatch stack to include higher-cost or inflexible generation that could not be economically absorbed, resulting in negative settlement prices to incentivise load or reduce generation.
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.