SA1 experienced a moderate price spike reaching $417.66/MWh at 19:25 on 21 June 2026, with elevated prices persisting across a two-interval window. Prices exhibited volatility during this period, alternating between high spikes ($412–$418/MWh) and lower levels ($311–$353/MWh).
The price spike was driven by binding constraints with marginal values between $3.90 and $7.79/MWh, indicating transmission or reserve limitations were active. The generation mix comprised primarily gas-fired capacity (OCGT and CCGT totalling approximately 1,208 MW), with minimal renewable contribution (52.29 MW wind, zero solar) and limited battery support (17.5 MW), suggesting tight supply conditions during evening peak demand when system flexibility was constrained.
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.