Commodity Demand — SA1: Saturday 6 June 2026

South Australia's spot price sits at $124.33/MWh at 06:30 AEST with demand at 1,373 MW — a significant step down from the evening peak that drove sustained pricing above $160/MWh between 03:05 and 05:55 AEST (17:05–19:55 UTC). That elevated price band coincided with demand tracking in the 1,340–1,410 MW range as solar generation was absent and gas plant carried the bulk of the load. The price-demand relationship across today's data is sharp: when demand climbed through 1,550–1,850 MW during the morning business ramp (roughly 17:00–19:00 AEST), prices held in the $103–$138/MWh corridor, supported by adequate dispatchable capacity. The standout episode was 24:00 AEST (14:00 UTC) when a single interval spiked to $187.71/MWh at 1,555 MW demand, and again at 00:50 AEST ($153.15/MWh, 1,570 MW) — both suggesting tighter marginal supply conditions at those moments rather than a structural demand signal.

Overnight demand troughed near 860–990 MW between roughly 14:00–15:30 AEST, where prices compressed to the low-to-mid $40s/MWh. The daily demand arc followed a classic winter weekday profile: pre-dawn trough, a sharp morning ramp from ~975 MW at 15:10 AEST to 1,847 MW by 18:35 AEST, a sustained plateau through midday, then gradual softening into the current 1,373 MW. Today being Sunday, demand will not replicate that weekday morning ramp; the trajectory is likely to stay 150–250 MW below equivalent weekday levels across the business hours window, which should keep prices from sustaining above $130/MWh absent a supply-side disruption.

The forward price signal supports that softer outlook. The most recent forecasts for the 07:00 and 07:30 AEST half-hours (21:00 and 21:30 UTC) are converging around $125–$126/MWh — broadly consistent with the current spot. Further out, load window forecasts show prices declining through $100/MWh into the sub-$70/MWh range from roughly 09:30 AEST onwards, bottoming near $10–$15/MWh in the early afternoon as minimal solar potential (today's forecast shows 16.4% average solar potential) still provides some midday generation easing, and wind remains low at 0.6 average potential. The evening ramp from approximately 17:30–19:30 AEST is again the key price risk window; with gas OCGT at 351.67 MW and CCGT at 254.26 MW currently covering the generation mix alongside 93.24 MW of wind and 41 MW of battery discharge, any tightening of interconnector capacity or a step-up in heating demand — current heating demand sits at 8.1 with a 9.9°C ambient temperature — could push the 19:00–21:00 AEST window back above $130/MWh.

Demand-side context from market notices is limited for SA directly today, though the Heywood interconnector constraint testing notice (increasing the SA-to-VIC test limit from