SA1 experienced sustained negative pricing at approximately −$3 to −$4/MWh across 3–4 consecutive intervals during the evening of 17 June 2026. The region was generating substantial renewable output, particularly from wind (1438 MW) and solar (337 MW combined), alongside battery and gas capacity that was unable to reduce load quickly enough.
Negative pricing resulted from oversupply relative to demand, driven by high renewable generation that could not be economically curtailed or exported. Multiple binding constraints with substantial marginal values (ranging from ~$70 to ~$98/MWh) indicate that transmission or network limitations prevented efficient dispatch of excess supply, forcing the market price negative to incentivise consumption or generation reduction within SA1.
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.