Commodity Demand — SA1: Friday 29 May 2026

South Australia sits at $18.86/MWh with demand at 1,324 MW as of 06:30 AEST — a level roughly 400 MW below the overnight peak of approximately 1,890 MW reached around 19:10 AEST and some 370 MW below the evening peak near 1,760 MW seen around 17:30 AEST. The current price reflects that compressed Saturday morning demand trough. What's notable in the price-demand relationship today is how tightly prices tracked demand through the day: as demand climbed from its overnight low of around 1,186 MW at 15:35 AEST toward the 19:10 AEST peak, prices only reached a modest $103.79/MWh — a fraction of the $108–$264/MWh levels observed during overnight trading (06:35–08:25 AEST on the prior period). That compression is explained by wind output of 1,353 MW now covering 97% of SA's demand at 0.0146 tCO2/MWh carbon intensity, keeping the gas fleet — 41 MW CCGT, 0.11 MW OCGT — almost entirely on the margin.

The demand trajectory from here shapes a cautious price outlook. Forecasts for the 07:00 AEST and 07:30 AEST half-hours are pegged at $23.76/MWh and approximately $31–48/MWh respectively, with forecast demand data zeroed out in the pre-dispatch runs, suggesting AEMO's dispatch engine is pricing on supply availability rather than a demand step-up. Being Saturday, the morning ramp that would occur on a weekday — with commercial and industrial load pulling demand back toward the 1,700–1,800 MW range by 09:00 AEST — is likely to be attenuated. Weather supports that view: Adelaide sits at 14.2°C with a heating demand index of only 3.8, cloud cover at 27%, and wind potential at 6.3 — conditions that limit both heating uplift and solar displacement effects through the morning.

Load window data points to sustained very low pricing from 09:30 through 11:30 AEST (prices forecast at -$11/MWh to -$2/MWh), aligning with wind potential strengthening to an average of 12.6 across today's outlook. This creates a credible negative price window in the early-to-mid morning as wind output remains high against low weekend demand — a meaningful signal for flexible loads and battery charging scheduling. The Heywood interconnector returned to full service at 19:20 AEST following the Heywood M1 transformer outage (Market Notice 144160), restoring SA-VIC transfer capacity; with SA generation currently surplus to demand, this provides an export pathway that will help underpin price suppression through the morning rather than forcing curtailment-induced price spikes.

The key demand risk for today's price outlook is how quickly SA demand recovers post-trough. If demand remains below 1,400 MW through the 09:00–12:00 AEST window against sustained wind output above 1,300 MW, negative prices in the -$2 to -$11/MWh range are the base case. A recovery toward 1,600–1,700 MW by the early afternoon — consistent with the prior period's weekend shoulder pattern — should see prices lift to the $30–$50/MWh range. The evening peak risk