Tasmania achieved 100% renewable generation on 4 July 2026 between 20:05 and 20:40 UTC, with hydroelectric output dominating at approximately 890–905 MW and wind contributing 44–71 MW. Regional reference prices ranged from $50.43–$71.70/MWh across the settlement period, with elevated prices persisting from 20:10 through 20:30 UTC despite the high renewable penetration.
The sustained elevated pricing during the 20:10–20:30 UTC window, despite 100% renewable generation, indicates that network constraints rather than generation costs were the primary price drivers. Multiple binding constraints with marginal values of $4.41–$7.97/MWh are present in the dispatch, suggesting that interconnector or regional transmission limitations restricted the economic dispatch of low-cost renewable output and necessitated higher-priced alternative sources or constrained supply elsewhere in the region.
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.