NSW1 experienced sustained negative pricing over two consecutive intervals (03:15 and 03:20 on 14 July 2026), with prices reaching −$1.26/MWh. The negative prices followed a sharp price decline from $10.94/MWh to $0.01/MWh across four intervals, suggesting a rapid shift in supply–demand balance during early morning hours.
The generation mix indicates exceptionally high renewable generation (solar 1952.64 MW and wind 1599.85 MW) coinciding with low demand typical of 03:00–03:20 periods, creating excess supply. A binding constraint with marginal values of $3.93–$4.93/MWh was active across the negative pricing intervals, indicating the constraint was preventing efficient dispatch and forcing generators to offer at negative prices to maintain grid stability. The combination of surplus renewable output and an active network or system constraint driving the marginal value suggests generators were paying to exit the market rather than curtail output.
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.