Tasmania (TAS1) achieved 100% renewable energy penetration on 18 May 2026 during the evening peak period, with Regional Reference Prices (RRP) remaining stable around $96.22/MWh. The renewable generation was predominantly supplied by hydroelectric output (approximately 2,952 MW combined across multiple generators) supplemented by wind generation (approximately 272 MW), with minimal thermal generation required.
The high renewable penetration was driven by strong hydroelectric availability in Tasmania, which typically operates at high capacity factors during this period, combined with moderate wind generation contributions. The stable and relatively moderate pricing despite 100% renewable penetration suggests adequate supply to meet demand without scarcity, though binding network constraints on the Tasmanian main feeders (F_MAIN+LREG and F_MAIN+RREG) with marginal values of $7.77–$8.49 indicate transmission limitations were active in managing the high renewable output and preventing further price suppression.
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.