Commodity Demand — SA1: Thursday 9 April 2026

South Australia's spot price sits at -$3/MWh with demand at 1,419 MW as of 06:35 AEST — a relatively low load level consistent with the post-sunset, early-evening shoulder period on a Friday autumn day. The price has been negative or near-zero for the entire session visible in the data, with only a brief excursion into positive territory around 21:20–21:25 AEST (reaching $2.13/MWh) when demand nudged above 1,540 MW mid-afternoon. That narrow positive window underscores just how little demand uplift is needed to flip the sign of the price from negative to marginally positive under current supply conditions. Wind is generating 799 MW and gas CCGT is contributing 82 MW, with solar now at zero following sunset; the grid is running at 90.7% renewable penetration.

Demand has followed a clear shape through the day: a trough around 1,330–1,350 MW between 03:30–04:45 AEST (overnight low), a climb to a daytime peak of approximately 1,874 MW around 11:50–12:00 AEST, then a steady decline through the afternoon back toward current levels. Prices tracked that demand curve loosely but remained overwhelmingly negative throughout — the daytime peak of ~1,874 MW produced prices only in the -$3 to -$5/MWh range, pointing to sustained supply surplus even at the day's highest demand. The single deepest negative print in the session was -$59.04/MWh at 17:30 AEST when demand was around 1,662 MW — a supply-side dynamic rather than a demand-driven event.

Looking ahead through tonight, demand is forecast to rise again from its current 1,419 MW as the evening residential ramp builds. The near-term forecast RRPs for the 21:00 and 21:30 AEST intervals are clustered between -$3 and -$0.10/MWh, consistent with the pattern seen today — demand growth into the 1,600–1,800 MW range has not been sufficient to push prices into sustained positive territory given current wind output. The load window data signals that prices between 09:30–14:30 AEST tonight (UTC) are forecast to reach -$20 to -$59/MWh, implying a fresh overnight surplus episode as demand drops back toward the 1,300–1,400 MW range and wind generation continues.

For demand-side participants, the practical implication is that today's price structure rewards load-shifting into overnight periods where forecast prices fall well below -$20/MWh, with the deepest windows projected around 02:30–04:30 AEST tomorrow morning. The brief positive-price window seen around 21:20 AEST today — driven by demand rising above 1,530 MW — is the most plausible repeat scenario for tonight's evening peak if demand tracks toward or above that level, though the forecast suggests that event will be short-lived and shallow.