Commodity Demand — SA1: Tuesday 11 August 2026
South Australia's spot price sits at $9.59/MWh at 06:30 AEST with demand at 1,535 MW — a subdued combination reflecting wind generation of 1,847 MW comfortably covering overnight and early-morning load. Prices have been pinned near zero or negative through most of the evening and overnight period (11 August 18:00–24:00 AEST), with several intervals printing between -$6/MWh and $0/MWh as wind output outstripped demand, which fell as low as 1,062 MW around 04:15 AEST. This is a textbook oversupply pattern: with wind meeting 97.7% of instantaneous renewable share and gas contributing under 43 MW combined, price has almost no sensitivity to demand movements in this range — the market simply absorbs load at near-zero cost while wind remains strong.
The forecast trajectory today points to a sharp reversal. AEMO's forward curve shows prices climbing from single digits at 07:00 AEST to $57.95/MWh by 07:00, then accelerating through the morning ramp to $83–90/MWh by 08:00-08:30, and peaking near $99–104/MWh between 09:00 and 10:30 AEST as demand builds through the morning shoulder toward typical winter peak levels of 1,900-2,000+ MW (consistent with yesterday's comparable period, which saw demand reach 2,013 MW alongside prices in the $70-80/MWh band). This morning peak reflects the classic winter demand-price relationship in SA: as load climbs past ~1,900 MW, wind alone can no longer cover the full load profile at these price levels, pulling gas and interconnector flows into the stack and lifting marginal price sharply. Prices are forecast to ease back to the $50-60/MWh range through midday as solar contributes, before a second smaller afternoon peak near $55-56/MWh around 14:00-14:30 AEST, then falling toward $17-20/MWh by early evening.
Today's weather outlook caps solar potential at just 3.6% average and wind potential at a moderate 8.3%, with cloud cover at 55% — softer renewable conditions than yesterday's overnight wind surge, reinforcing the forecast price lift during the demand ramp. Traders should note AEMO's active Reserve Notice flagging low reserve conditions for SA in July 2028, unrelated to today's operations but indicative of tightening medium-term adequacy. No demand-side constraints or directions are currently active for SA1; the most recent SA intervention event (voltage-related, 8 August) was cancelled and does not affect today's outlook. The key trading window remains the 08:00-10:30 AEST ramp, where demand crossing the 1,900-2,000 MW threshold is forecast to double or triple current prices within three hours.