Commodity Demand — SA1: Saturday 11 July 2026
South Australian demand sits at 1,391 MW as at 06:25 AEST, with spot price at -$1.07/MWh — firmly negative territory as wind generation of 1,696 MW outstrips local load by over 300 MW. This follows a demand trough overnight (as low as 1,360 MW around 05:35 AEST local settlement time) after peaking near 2,197 MW during yesterday's evening period around 18:25-18:55 UTC (04:25-04:55 AEST), when prices spiked to $44-48/MWh as demand crossed the 2,100 MW threshold. The relationship is clear: SA prices track demand tightly once wind output is saturated, with every 100 MW step above ~1,900 MW adding roughly $10-15/MWh over the past 24 hours.
Today's forecast trajectory points to sustained negative-to-low pricing through the morning and into midday. AEMO's forecast curve shows prices holding around -$1 to -$7/MWh from 07:00 through 13:00 AEST, before a modest firming to $7-13/MWh in the 17:00-21:00 AEST window as demand rebuilds into the evening peak. This is consistent with the wind-heavy supply picture — current wind potential sits at 17.1% of capacity with generation at 1,696 MW against only 42.7 MW of gas CCGT and negligible OCGT, leaving the region 97.5% renewable-supplied with carbon intensity of just 0.012 tCO2/MWh.
The key price-sensitivity threshold for today is around 1,900-2,000 MW demand — below this, SA remains awash with wind and prices stay negative or near zero; above it, gas peaking units set the marginal price, pushing spot into the $20-50/MWh range as seen in yesterday's 07:00-10:00 AEST window. With today's forecast wind potential at 16.3% (similar to current conditions) and cloud cover at 38%, solar contribution will be limited (7.4% potential), meaning any demand surge this evening will likely need gas to firm supply, keeping a repeat of yesterday's $40+ pricing plausible during the 17:00-19:00 AEST period.
No SA-specific demand-side constraints are active in current market notices — the SA reserve condition flagged for 14 July has already been cancelled, and today's only regional interconnector activity relates to VIC/NSW network work with no direct SA demand impact.