SA1 experienced sustained negative pricing at -$6.01/MWh for two consecutive intervals on 17 June 2026 at 11:45–11:50, representing a minor severity event. Prices recovered quickly to near-zero in the following interval, with the region's generation mix dominated by wind output of 1762 MW and supported by battery and gas generation.
The negative pricing reflects an excess supply condition in SA1 during the settlement periods, likely driven by high wind generation coinciding with low demand. Multiple binding constraints with marginal values between $3.02 and $3.37/MWh constrained the region's ability to export surplus generation, forcing the residual balance toward negative pricing to clear the market. The rapid price recovery within one interval suggests the constraint tightness was transient and demand or generation conditions shifted quickly.
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.