Tasmania experienced very high renewable penetration of 91.6% on 28 August 2026, driven by substantial hydro generation (approximately 2.8 GW combined) and wind output (around 713 MW). Notwithstanding the high renewables contribution, regional electricity prices increased noticeably from around $68–$78/MWh to $122–$125/MWh between 06:05 and 06:30, suggesting constraint-driven pricing pressure despite abundant clean generation.
The price elevation was driven by binding constraints, particularly constraint F_TASCAP_RREG_0220 which carried marginal values of $7.79–$9.87/MWh across multiple settlement intervals, indicating this transmission or reserve regulation limit was active in restricting dispatch flexibility. A secondary constraint (F_T+RREG_0050) with a marginal value of $5.43/MWh also bound during the period. Together, these binding constraints limited the region's ability to utilise its abundant renewable capacity, forcing higher-cost generation to meet demand and creating the observed price spike despite renewable availability.
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.