The WEM in WA1 experienced a moderate price spike to $253.22/MWh during the 13:40 settlement interval on 17 June 2026, representing a sharp 81% increase from the preceding interval. Prices remained elevated at $253.22 in the following interval before declining slightly to $245.56, indicating a brief but sustained constraint-driven event.
The price spike was driven by multiple binding constraints, all designated F_MAIN+RREG_0220, which carried marginal values ranging from $4.97 to $6.80/MWh and were the primary marginal drivers during this period. The elevated price generation mix, which was heavily reliant on relatively expensive generation sources (GAS_OCGT at 1265.95 MW and GAS_CCGT at 574.71 MW), combined with the active constraint limitation, created conditions for the substantial price elevation observed.
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.