A major binding constraint (T_BLINK_TV_NGZ) with an exceptionally high shadow price of $8.352 million/MWh became active in TAS1 during the evening of 17 September 2026, causing Tasmanian regional reference prices to spike to $88.20/MWh before declining as the constraint binding period subsided. The constraint remained the primary price driver across multiple dispatch intervals, with Tasmania's generation mix comprising predominantly hydro (approximately 2,949 MW) and wind (881 MW) sources during this period.
The extreme marginal value of the binding constraint T_BLINK_TV_NGZ indicates a severe physical or operational limitation preventing increased power transfer or generation in TAS1. The subsequent rapid price decline from $88.20 to $50.16/MWh over five dispatch intervals suggests the constraint either temporarily relaxed or underlying system conditions eased, allowing market-clearing at lower prices despite the persistent presence of other minor binding constraints with negligible shadow prices.
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.