Tasmania achieved 100% renewable energy generation during the 20:05–20:30 period on 21 June 2026, with hydro and wind providing all output whilst gas-fired generation remained offline. Regional spot prices remained stable around 70 AUD/MWh until 20:25, then increased to approximately 79 AUD/MWh in the final two settlements.
The price increase in the final two periods coincides with multiple binding constraints becoming active, most notably constraint T_BLINK_TV_NGZ with a marginal value of 7.308 million AUD/MWh, indicating severe congestion or network limitation. The tightening of supply-side flexibility as renewable generation dominated the mix—with hydro output ranging from 1226–1369 MW and gas-OCGT unavailable—likely reduced the region's ability to respond to changing demand or maintain reserve margins, driving the constraint-induced price lift despite high renewable penetration.
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.