Tasmania achieved 100% renewable energy penetration on 5 July 2026 between 20:05 and 20:35 UTC, with generation sourced entirely from hydroelectric (988–1430 MW) and wind (69–78 MW) sources. Prices rose steadily from $75.20/MWh to $88.26/MWh and remained at that level, suggesting constraint-driven pricing despite abundant renewable supply.
The binding constraints F_TASCAP_RREG_0220 and F_T+RREG_0050, which carried marginal values of up to $8.98/MWh and $4.21/MWh respectively, indicate that export or transmission capacity limitations rather than fuel costs were driving price formation. With gas generation offline and renewables fully adequate to meet local demand, these constraints appear to have limited inter-regional flows, pushing local prices upward as the market moved to clear at the constraint shadow price rather than at marginal generation cost.
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.