Commodity Demand — SA1: Friday 31 July 2026
South Australia's spot price sits at $101.02/MWh at 06:30 AEST with demand at 1,467 MW, well off the overnight peak of 2,137 MW recorded around 08:15 AEST yesterday evening when prices spiked to $534/MWh. Wind generation is currently supplying 897 MW against total demand of roughly 1,387 MW (battery 18 MW, gas OCGT 286 MW, gas CCGT 186 MW, solar at zero pre-dawn), keeping the region comfortably supplied and price-stable in this window. The price-demand relationship over the past 24 hours has been steep: every 200-300 MW step above 1,900 MW pushed prices past $300-400/MWh, with the $534.17/MWh peak coinciding with the 2,108 MW demand high — confirming SA's thin reserve margin converts demand spikes into disproportionate price responses.
The forecast trajectory today is bifurcated. Demand-driven pricing turns negative through the early morning trough, with AEMO forecasts showing $-6/MWh around 02:30-04:30 AEST as low heating demand (current 6.8°C, cooling demand zero) meets continued wind output. But the market flags a sharp reversal from mid-morning: forecast prices jump to $302/MWh by 09:00 AEST, then spike to $844-$1,001/MWh across the 10:00-11:00 AEST window — the steepest price escalation in the visible forecast curve. This aligns with today's weak solar outlook (avg solar potential just 22.6% for 1 August) and low wind potential (2%), meaning renewable supply cover will be thin exactly as morning demand ramps, a repeat of the pattern that drove yesterday's evening peak.
Grid stress conditions reinforce this outlook — the grid stress score sits at 74.6 against a market conditions score of just 50.8, and AEMO's active notices show recent LOR1/LOR2 reserve shortfall declarations for SA on 29 July tied to capacity margins as tight as 8-30 MW above requirement. Combined with an active non-credible contingency event at City West substation and ongoing VIC-SA interconnector constraint sets, the market has limited slack to absorb the forecast late-morning demand ramp. Traders should treat the 09:00-11:00 AEST window as the key exposure period today, with price risk skewed heavily to the upside if wind underperforms the already-soft 2% potential forecast.