SA1 experienced sustained negative pricing at approximately –$0.05–0.10/MWh across eight consecutive five-minute intervals on 7 August 2026 from 23:10 to 23:45. Wind generation dominated the mix at 1,458.78 MW, with solar and gas-fired plant providing supplementary output, creating a supply-demand imbalance that drove prices negative.
The negative pricing reflects oversupply conditions typical of high renewable penetration during low-demand periods, with wind generation significantly exceeding regional requirements. Binding constraints with marginal values of approximately $4.97–$5.46 indicate transmission or network limitations were active during the event; these constraints prevented the region from exporting excess generation or importing cheaper demand-balancing resources, trapping low-priced supply locally and compressing the spot price into negative territory.
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.