Tasmania experienced 100% renewable energy penetration on 12 July 2026 between 20:00 and 20:30 AEST, with wind and hydro generation totalling approximately 1,600 MW across the region. Regional reference prices fell into negative territory, ranging from −$1.18/MWh to −$7.35/MWh, reflecting surplus renewable generation.
The negative pricing resulted from high renewable generation exceeding regional demand, creating downward price pressure typical of low-demand periods with abundant wind and hydro output. The binding constraint with marginal values between $12.92/MWh and $14.45/MWh indicates an active network or system control limitation that restricted further dispatch of low-cost renewable generation, preventing prices from declining further and supporting the observed negative price floor.
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.