The WEM experienced a moderate price spike in WA1 on 14 September 2026 at 06:25, with the region price reaching $261.79/MWh—a sharp increase from $181.80/MWh five minutes earlier. The spike was isolated to a single five-minute trading interval during the early morning period.
The price spike was driven by multiple binding constraints, with the constraint F_T++NIL_MG_R6 contributing the largest marginal value of $52.14/MWh, followed by F_T++NIL_CHWF_TG_R6 at $32.47/MWh. These binding constraints collectively limited available generation supply at a time when the system was relying on a diverse generation mix including coal (661.76 MW), gas (791.45 MW combined CCGT and OCGT), and wind (425.34 MW), suggesting that supply-side restrictions rather than demand-driven factors were the primary driver of the sharp price movement.
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.