South Australia (SA1) experienced a moderate price spike reaching $314.65/MWh on 21 June 2026 at 07:45 UTC, with elevated pricing sustained across two consecutive intervals. Prices rose sharply from the $260 range to the $310+ range within a five-minute window, representing a 20% increase from baseline conditions.
The binding constraint F_T+RREG_0050 operated with a marginal value of $325.05–$325.03 during the spike intervals, closely aligned with the observed regional reference price and indicating this constraint was the primary driver of price elevation. The secondary binding constraint F_T++NIL_MG_R60 (marginal value ~$285) suggests multiple simultaneous limitations on supply or transmission capacity, with the dispatch system forced to call higher-cost generation to satisfy demand while respecting these active constraints.
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.