South Australia (SA1) experienced very high renewable penetration of 95.5% on 17 June 2026 at 11:15 UTC, driven predominantly by wind generation of 1,762 MW. During this period, regional electricity prices collapsed to $1.78/MWh at 11:15 UTC, reflecting the abundant renewable supply, before recovering to $7–9/MWh in subsequent periods.
The low price spike at 11:15 UTC reflects the oversupply conditions created by high wind output coinciding with minimal solar and gas generation requirements. Multiple binding constraints with marginal values between $3–4/MWh, including constraints associated with Tasmania-South Australia interconnection regulation services, suggest that transmission limits and system service requirements are constraining the dispatch of available renewable generation, preventing further price suppression despite the renewable surplus.
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.