Commodity Demand — SA1 — Thursday 7 May 2026

South Australia's spot price sits at $36.91/MWh with total demand at 1,408.6 MW as of 06:30 AEST — well off the day's peak and tracking a clear post-morning-ramp descent. The price-demand relationship across today's data is pronounced: demand climbed from a overnight trough near 920 MW (where prices repeatedly touched zero or negative) through a morning peak of 1,940 MW at around 18:40 AEST, where prices held firmly in the $52–$56/MWh band. That $56/MWh ceiling proved sticky through the 17:40–19:25 AEST window despite demand varying by over 100 MW, suggesting gas CCGT marginal cost is anchoring the upper price band. The two notable price spikes to $119–$120/MWh at 22:15, 22:40, 01:05 and 01:15 AEST occurred against mid-range demand of 1,446–1,535 MW, pointing to brief supply tightness or dispatch constraint events rather than demand-driven pressure.

Demand is now falling through the post-morning transition, down from 1,459 MW at 06:20 AEST and expected to continue declining as the Friday business day winds toward its solar trough — though with 100% cloud cover today and zero solar potential, the midday demand suppression from rooftop PV that typically compresses SA prices toward or below zero will be absent. Wind is providing 362.7 MW with gas CCGT contributing 104.4 MW; solar generation is nil. This cloud-driven dynamic is material: on clear autumn days SA prices routinely go negative between 10:00–15:00 AEST. Today that mechanism is not available, so prices are forecast to hold in the $20–$36/MWh range through the afternoon rather than collapsing.

Forward forecasts for the 07:00–09:30 AEST window (21:00–23:30 UTC) converge tightly between $19–$36/MWh, a significant step down from morning peak pricing. The trajectory from $36.91/MWh now toward a forecast $9–$10/MWh by 09:00–09:30 AEST reflects the typical Friday demand fade as commercial load eases, combined with wind maintaining output. Demand is not expected to re-test the 1,800+ MW morning peak today. The active market notice to watch is the Armidale No.3 transformer outage in NSW invoking constraint set N-AR_TX on interconnector N-Q-MNSP1 from 05:15 AEST — this is a NSW/QLD constraint and carries no direct binding impact on SA pricing, but any flow displacement across the eastern grid could marginally influence SA interconnector headroom on the Heywood link.

The Friday demand profile and overcast conditions together define today's price outlook: no negative midday prices, no demand-driven evening spike above $60/MWh barring an unplanned generation outage, and a broadly soft $10–$35/MWh range dominating the remainder of the trading day. Flexibility-seeking load managers face a less favourable arbitrage window than a sunny weekday would offer, given the absence of negative pricing in the afternoon. The evening ramp from approximately 17:30 AEST warrants monitoring — last night that period produced prices up to $58.58/MWh against demand of 1,418