NSW1 experienced sustained negative pricing at $-2/MWh during the 03:25 interval on 25 July 2026, with a second negative interval at $-1.22/MWh, representing a minor pricing event. The region transitioned from positive pricing around $23.95/MWh to negative territory over a brief window, with prices recovering to positive levels immediately after.
The negative pricing occurred during a period of high renewable generation (3,420 MW combined solar and wind) alongside significant battery discharge (500.4 MW), creating excess supply relative to demand in the early morning period. The binding constraints, particularly those related to regulation services (F_TASCAP_LREG_0210 and F_TASCAP_RREG_0220 with marginal values of 4.07 and 4.05 respectively), indicate that network regulation requirements were constraining dispatch and limiting the market's ability to absorb the available generation without accepting negative prices.
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.