The WEM in WA1 experienced a moderate price spike to $276/MWh at 03:40 UTC on 3 July 2026, representing a 75% increase from the preceding interval's $158.16/MWh. The spike was isolated to a single 5-minute trading interval before prices subsequently adjusted.
The price spike occurred under conditions of elevated system demand with significant reliance on thermal generation (Black Coal 939 MW, Gas CCGT 573 MW, Gas OCGT 544 MW) and battery output (642 MW), suggesting tight supply-demand balance. Binding constraints with marginal values between $2.55–$4.02/MWh, predominantly the constraint F_T+RREG_0050, indicate that system security or network limitations were constraining available generation, forcing the market price to the offer of the marginal generator required to meet demand within those 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.