SA1 experienced sustained negative pricing at −$3.29/MWh during the 21:40 settlement interval on 2 July 2026, with negative prices occurring in 2 of 7 intervals sampled. The region's generation mix was dominated by wind (1,442 MW) and battery storage (215 MW), with minimal demand from conventional gas generation.
The negative pricing reflects excess renewable generation relative to regional demand, typical of high wind output during low-demand evening periods. Multiple binding constraints with varying marginal values—particularly the regulation constraint (F_T+RREG_0050) with marginal values between $4.00–$6.14/MWh and the raise regulation constraint (F_T+LREG_0050) at $49.99/MWh—indicate the system faced binding operational limits that prevented efficient absorption or export of surplus wind generation, forcing prices negative to incentivise load or suppress further supply.
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.