Regional Outlook — SA1: Friday 4 September 2026
South Australia's spot price sits at -$4.84/MWh at 6:35am AEST, holding in negative territory for a fifth consecutive hour as strong wind generation continues to outpace demand. This is a sharp reversal from yesterday evening's peak of $156.56/MWh at 8:10am AEST (08:10 UTC settlement), when demand climbed above 1,750 MW during the evening ramp. Prices have been negative or near-zero for most of the overnight and early morning period, with troughs of -$69.67/MWh around 7:20pm AEST and -$59/MWh shortly after, reflecting periods of minimal operational demand against high renewable output. Current demand sits at 1,211 MW, well down from yesterday's 1,700+ MW afternoon peak.
The generation mix is currently dominated by wind at 1,341 MW, against gas CCGT at 82 MW, gas OCGT at 0.11 MW, and negligible battery and solar output given overnight conditions. This puts renewable penetration at 94.23% and carbon intensity at 0.0283 tCO2/MWh, both consistent with the pattern seen through the day — renewable share has held above 94% since mid-afternoon yesterday and peaked near 98% overnight and through the middle of the day. Wind potential in the current weather reading is 28.1%, with today's outlook showing average wind potential of 33.3% and solar potential of just 12.5% under 48% cloud cover, consistent with the wind-led mix persisting through the day.
Predispatch forecasts point to prices staying negative through the morning, with troughs of -$43.09/MWh forecast around 2:30pm AEST and -$32.95/MWh near 3:30pm AEST, before recovering to the $18-35/MWh range through mid-morning and early afternoon trading. A sharper lift to $71.88/MWh is forecast for the 6:00pm AEST target, signalling a return of evening demand pressure. Load-shifting windows align with this trajectory — the five identified low-risk windows all fall between 1:00pm and 4:30pm AEST, with the best opportunity around 2:30-3:30pm AEST offering average prices near -$36/MWh and estimated savings of $108/MWh versus peak.
Several active notices are relevant to SA today. AEMO reclassified a non-credible contingency event for the Para-Templers West and Magill-Torrens Island A 275kV lines as credible from midnight due to a severe weather warning, effective until further notice. A foreseeable AEMO intervention notice for voltage conditions was also issued yesterday, following an earlier direction issued to a market participant (Torrens Island) under section 116 of the National Electricity Law — that direction was subsequently cancelled at 2:19pm AEST. Separately, an unplanned outage of the Keith-Kincraig 132kV line at 9:36pm AEST triggered an inter-regional transfer constraint (S-KHKN) affecting the Victoria-SA interconnector, still in effect. A forecast Minimum System Load (MSL1) event for 10 September has been cancelled. Traders should watch for further voltage-related intervention given the active severe weather reclassification and the tight overnight negative pricing pattern.