The WEM in WA1 experienced a sharp price spike to $812.60/MWh in a single trading interval at 23:55 on 6 July 2026, more than four times the preceding price level of $172.71/MWh. The price returned to more typical levels ($202.44/MWh) in the following interval, indicating a localised, short-duration market stress event.
The spike occurred despite a substantial generation fleet with 2,744 MW of total capacity online, including significant thermal (1,868 MW combined coal and gas) and renewable (770 MW wind) output, suggesting supply availability was not critically constrained. The binding constraints identified—including F_TASCAP_RREG_0220 with a marginal value of $8.99/MWh and several regulation raise constraints—indicate the price pressure was driven by operational limitations on available generation rather than absolute capacity shortage, with multiple regulation service constraints binding simultaneously.
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.