TAS1 experienced sustained negative pricing at −$15/MWh across two consecutive intervals (05:05 and 05:10 on 8 September 2026), representing a minor severity event. Prices rebounded to the $24/MWh range in surrounding intervals, indicating the negative pricing was localised and temporary.
The negative pricing occurred during a period of substantial renewable generation, with wind output exceeding 412 MW and combined hydro generation around 975 MW, creating excess supply conditions in the region. Multiple binding constraints with marginal values between $16 and $35/MWh were active during this period, indicating transmission or operational limitations that constrained the ability to export or utilise excess generation, forcing prices negative to incentivise demand response or reduce generation.
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.