The WEM in WA experienced a major price spike to $307.06/MWh during the 10:25 UTC interval on 27 August 2026, representing a 120% increase from the previous interval at $166.17/MWh. The spike was isolated to a single five-minute trading interval before prices did not continue at elevated levels in the immediate subsequent intervals shown.
The price spike occurred with a binding constraint (F_T+RREG_0050) holding a marginal value of $3.44/MWh, indicating that this constraint was active in determining the market price. The generation mix at the time showed substantial reliance on gas-fired generation (1,394 MW combined OCGT and CCGT) and battery discharge (397 MW), with moderate wind contribution (581 MW), suggesting potential supply-side tightness or rapid demand variation that activated the binding constraint to clear the market at a significantly higher price point.
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.