TAS1 experienced sustained negative pricing at –$3/MWh across two consecutive intervals (02:15 and 02:20 on 16 August 2026), representing a minor severity event. Prices declined sharply from positive territory ($1.79/MWh) through near-zero readings to negative values within a 25-minute window.
The negative pricing was driven by multiple binding constraints with substantial marginal values (ranging from $3.35 to $3.44/MWh), indicating tight system conditions preventing export of surplus generation. Hydro generation remained elevated at approximately 500 MW throughout the period, and with minimal wind output (12–20 MW) and moderate gas-fired generation (124 MW), the inability to dispatch excess supply—as evidenced by the binding constraint shadows—forced prices negative to incentivise demand or curtailment.
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.