SA1 experienced sustained negative pricing across five consecutive intervals between 16:20 and 16:50 on 11 August 2026, with prices ranging from $0/MWh to $-0.09/MWh. The region's generation mix was dominated by wind generation (1680.91 MW) with minimal demand for flexible capacity.
The negative pricing reflects oversupply conditions in SA1 during this period, driven by high wind generation coinciding with low demand. The binding constraint F_T+LREG_0050 maintained consistently high marginal values (approximately $88.62–$88.72/MWh across all intervals), indicating this constraint was actively restricting generator dispatch; the high shadow price suggests physical or operational limits on that constraint forced generators to operate despite insufficient demand, resulting in negative prices as an economic signal to reduce output.
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.