Tasmania's electricity grid operated at 100% renewable penetration on 31 May 2026 between 20:05 and 20:30, with hydroelectric generation dominating supply at approximately 850–1,060 MW complemented by wind generation of 150–237 MW. Regional reference prices (RRP) remained relatively stable in the $80–87/MWh range throughout the period, with minor volatility suggesting a well-balanced market without significant supply-demand stress.
The 100% renewable penetration reflects Tasmania's abundant hydroelectric resources and favourable wind conditions during the evening peak, eliminating any requirement for thermal generation. The binding network constraints (F_MAIN+RREG_0220 and F_T+RREG_0050) with marginal values of $4–8/MWh indicate that transmission limits rather than fuel scarcity were the primary market constraint, typical of Tasmania's export-constrained interconnection with the mainland, which moderately elevated prices despite oversupply of renewable energy within 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.