TAS1 experienced sustained negative pricing with rates reaching -$9.17/MWh across three consecutive intervals during the early morning period of 5 September 2026. The sharp decline in prices followed a spike to $30.15/MWh, suggesting rapid supply-demand imbalance correction.
The negative pricing appears driven by oversupply conditions in Tasmania, with wind generation reaching 473 MW and total renewable output (hydro and wind combined) exceeding 1,000 MW during the affected period. Multiple binding constraints with marginal values between $4.21 and $8.03/MWh constrained system flexibility, preventing efficient load matching and forcing generators to pay for dispatch during low demand conditions in the early morning period.
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.