NSW1 experienced sustained negative pricing with a minimum of -$3.08/MWh across 2 intervals during the early morning period of 1 September 2026. The negative prices occurred within a broader pattern of low to volatile pricing ranging from -$3.08 to $23.95/MWh over an 8-interval window.
The negative pricing was driven by very high solar generation (3,487 MW) combined with substantial wind generation (939 MW) during a low-demand overnight period, creating oversupply conditions. A binding constraint (F_TASCAP_RREG_0220) with declining marginal values across the intervals suggests transmission or regulatory limits were active, which likely restricted the ability to export excess renewable generation and contributed to local price depression in NSW1.
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.