Tasmania experienced sustained negative pricing in two intervals during the early morning of 31 August 2026, with the lowest price reaching −$3.84/MWh at 03:35. The event occurred during a period of moderate renewable generation, with approximately 350 MW of hydro and 160–190 MW of wind supplying the region.
The negative pricing was driven by a binding constraint (F_T+RREG_0050) with marginal values around $4.38–$4.39/MWh, indicating dispatch limitations were active during these intervals. With gas-fired generation offline and combined renewable output around 520–540 MW, the constraint prevented adequate load shedding or generation reduction, forcing the market price below zero to manage excess supply and balance the system.
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.