QLD1 experienced sustained negative pricing during two intervals on 28 May 2026 at 04:25–04:30, with minimum prices reaching -$7.33/MWh, indicating oversupply conditions in the early morning period. The event was relatively minor and brief, occurring within a broader pattern of negative pricing between 04:25 and 04:50, with prices deteriorating further to -$25/MWh in subsequent intervals.
High solar generation (3,353.47 MW combined across two entries) combined with substantial wind output (902.39 MW) created significant oversupply during dawn hours when demand remains relatively low, pushing prices into negative territory. Active binding transmission constraints—particularly F_MAIN+LREG_0210 (marginal value $25.10)—restricted the ability to export excess generation out of QLD1, trapping renewable output in the region and forcing generators to pay to dispatch or curtail, driving prices negative.
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.