Commodity Demand — SA1: Monday 15 June 2026

South Australia's spot price sits at -$0.09/MWh at 06:00 AEST with demand at 1,493 MW — a level that tells the full story. Wind is generating 1,772 MW against total demand of under 1,500 MW, meaning generation is exceeding local consumption and prices are being pushed negative. This oversupply dynamic has been persistent since around 13:30 AEST yesterday, when prices collapsed from the $50–$65/MWh range to near zero and below as demand fell away from its morning peak of roughly 2,076 MW. The 580 MW demand drop from that peak to current levels, combined with sustained wind output, is the direct driver of the current negative price regime.

The intraday demand arc traced today is instructive. Demand climbed from around 1,480 MW in the early hours through to a peak above 2,000 MW during the 07:00–09:00 AEST morning window, where prices responded accordingly — ranging from $72/MWh to $140/MWh, with a spike to $139.89/MWh at 07:15 AEST when demand hit 2,006 MW. That price sensitivity at the 2,000 MW threshold is clear: once demand drops below roughly 1,700 MW and wind output holds, the market tips negative. The afternoon and evening periods confirm this pattern, with demand retreating through 1,500–1,400 MW and prices staying sub-zero from 16:00 AEST through to the current interval.

The forward curve reflects a very similar daily shape repeating today. Prices are forecast to remain low overnight — in the $5–$17/MWh range through to 06:30 AEST — before rising to $40–$65/MWh across the 06:00–10:00 AEST morning demand peak. From there, forecasts show prices collapsing back through midday and into deeply negative territory again from 13:30 AEST, reaching -$3.00/MWh by 04:00 AEST tomorrow as the afternoon wind-oversupply window reopens. The 100% cloud cover and zero solar potential today means solar provides no demand offset, leaving wind as the sole variable shaping price outcomes.

One forward risk worth flagging: AEMO issued a Forecast LOR1 notice for SA on 17 June, covering 08:00–09:30 AEST and 16:30–22:30 AEST, where forecast capacity reserves fall below the 320 MW requirement. That notice was subsequently cancelled on 11 June, but the proximity of that event — combined with the tight reserve margins flagged — is a reminder that the current negative-price environment does not preclude rapid tightening if wind drops or interconnector constraints bind during a cold morning demand peak.