Commodity Demand — SA1: Monday 31 August 2026
South Australia's spot price sits at $14.15/MWh at 06:30 AEST with demand at 1,427 MW, a level that's held broadly steady overnight into the early morning ramp. This masks significant volatility beneath the surface: prices swung from -$6.62/MWh at 04:40 AEST (demand 1,405 MW, negative pricing driven by 1,729 MW of wind output against soft overnight load) up to $120.54/MWh at 08:45 AEST yesterday when demand peaked near 1,684 MW during the morning ramp. The relationship is clear — every 200-300 MW of demand increase through the 07:00-09:00 AEST window has historically pushed prices from sub-$20/MWh into the $100-125/MWh band as wind generation alone can't cover the ramp and gas plant sets the marginal price.
Wind is currently supplying 1,729 MW against total demand of 1,427 MW, meaning SA is a net exporter to the rest of the NEM at this hour, with battery storage contributing 78 MW and gas (CCGT/OCGT) trimmed back to just 41 MW combined. Renewable penetration sits at 97.8% and carbon intensity is exceptionally low at 0.0108 tCO2/MWh. This oversupply explains the negative-to-low pricing pattern seen through yesterday afternoon and evening, with multiple intervals between 14:00-19:00 AEST settling below $0/MWh as demand hovered in the 1,330-1,440 MW range against strong wind output.
The forecast trajectory points to continued price weakness overnight before a modest recovery through the day. AEMO's forward curve shows prices bottoming around -$46/MWh near 14:00 AEST target time (04:00 local overnight), then climbing steadily from -$8/MWh at 16:00 AEST through to $27-30/MWh by mid-morning, and firming further into the $45-68/MWh band across midday and early afternoon as demand builds and solar contribution fades with cloud cover forecast at 75% today. Wind potential remains moderate (5.6 average) with today's peak temperature of 19.9°C limiting cooling load, so demand-side pressure should stay manageable — no minimum system load or intervention notices are currently active for SA today, though the pattern of repeated MSL1 advisories over the past week (29-31 August, with minimum demand troughs of -62 MW to 168 MW around 13:00-15:00 AEST) signals SA continues to run periods of very low operational demand that flip pricing negative during high-wind, mild-weather middays.
Traders should watch the 07:00-09:00 AEST ramp for the sharpest price response to demand growth, given the consistent historical pattern of $100+/MWh spikes as load climbs past 1,500 MW while wind cannot fully cover the increase. The afternoon low-demand window (13:00-15:00 AEST) carries elevated risk of negative pricing given yesterday's precedent and the forecast's own -$46/MWh trough, reinforcing SA's characteristic split-personality day: negative or near-zero pricing in shoulder periods, sharp positive spikes at the morning and evening ramps.