NSW1 experienced sustained negative pricing of approximately $-4/MWh across two consecutive intervals (23:15 and 23:20 on 2026-09-01), a minor severity event. The region's generation mix was dominated by solar (2,865 MW) and wind (1,097 MW) with substantial black coal baseload (2,802 MW), creating an oversupply condition during the evening shoulder period.
The negative pricing was primarily driven by high renewable generation (nearly 3,962 MW of solar and wind) exceeding demand and inflexible baseload coal generation, forcing marginal generation to accept negative prices to remain dispatched. The binding constraint T_BLINK_TV_NGZ exhibited an exceptionally high marginal value of $8.352 million, indicating severe congestion or network limitations that prevented efficient dispatch of excess renewable generation and exacerbated the supply-demand imbalance in NSW1.
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.