SA1 experienced very high renewable penetration of 96.9% during the settlement period 4 September 2026, with wind generation reaching 1181 MW and solar contributing 217.67 MW combined. Regional prices turned negative in several intervals (−$0.52/MWh to −$1.10/MWh), indicating excess supply relative to demand.
The negative and near-zero pricing reflects oversupply conditions driven by high wind and solar output during an off-peak period (00:05–00:30 hrs). Binding constraints F_TASCAP_RREG_0220 and F_T+RREG_0050, with marginal values of $4.67–$6.99/MWh, indicate active constraint-binding on network elements, likely limiting the export of surplus generation and forcing local prices downward as renewable output must be accommodated within regional boundaries.
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.