NSW1 experienced sustained negative pricing at −$2/MWh for one interval (05:15) on 26 August 2026, with prices declining from $73.30/MWh in the preceding interval. The negative pricing event occurred during high solar generation (2,892 MW) and elevated wind generation (281 MW) in a system with substantial black coal output (4,362 MW), creating oversupply conditions in the early morning period.
The negative price was driven by a generation surplus relative to demand during high renewable output periods, combined with binding constraints that limited the ability to export excess generation or reduce thermal output economically. Multiple binding constraints with marginal values between $9.48/MWh and $36.96/MWh restricted system flexibility, preventing efficient load shifting or dispatch adjustments that would have rebalanced supply and demand without resorting to negative pricing to incentivise load uptake or generation withdrawal.
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.