SA1 experienced sustained negative pricing at –$2/MWh for two intervals (04:40 and 05:10 on 14 June 2026), with prices remaining negative or near-zero across an eight-interval window. The region had high renewable generation (900.62 MW from wind and solar combined) during overnight/early morning hours when demand was low, creating excess supply conditions.
The negative pricing reflects oversupply of zero-marginal-cost renewable generation during low-demand periods, requiring generators to pay for dispatch. Binding constraint F_MAIN+RREG_0220 remained active across most intervals with elevated marginal values (7.62–4.96), indicating transmission or network support limitations that constrained the region's ability to export excess renewable output, thereby forcing prices negative. The persistent constraint binding suggests SA1 was unable to relieve local surplus generation through standard interconnection flows.
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.