Tasmania achieved 100% renewable energy penetration on 20 September 2026, with hydro and wind generation totalling approximately 2,506 MW across the settlement period. Regional reference prices exhibited high volatility, ranging from $0/MWh to $139.02/MWh, with particularly sharp increases observed in the final two settlement intervals.
The price volatility despite high renewable penetration was driven by binding constraints with substantial marginal values, particularly constraint F_T_NIL_MINP_R6 (marginal value $61.51/MWh) and F_T+RREG_0050 (marginal value $55.61/MWh), which imposed increasing scarcity on dispatch. The sharp price escalation in later intervals suggests constraint tightening coincided with declining wind generation (from 433.95 MW to 358.35 MW across the period), reducing overall renewable supply flexibility and triggering binding constraint penalties that drove prices significantly above zero despite 100% renewable generation.
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.