South Australia (SA1) experienced two consecutive intervals of negative pricing at −$7/MWh on 6 July 2026 at 13:40–13:50, following a sharp price spike to $52/MWh in the preceding interval. The negative pricing was brief and of minor severity, with prices recovering to $0.46/MWh by 13:55.
The sustained negative pricing reflects an oversupply condition typical of high wind generation (1,579.69 MW) combined with constrained export capability. The binding constraint F_S+TBTU_L1 held active during this period with marginal values ranging from $40–$95/MWh, indicating that a network constraint was limiting the region's ability to export excess generation, forcing the dispatch stack to accept negative prices to maintain balance. The sharp price recovery to $52/MWh immediately prior suggests rapid demand or generation changes that temporarily resolved the oversupply before negative pricing emerged.
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.