Commodity Demand — SA1: Wednesday 17 June 2026

South Australia sits at -$2/MWh at 06:30 AEST with demand at 1,488 MW — a low-load, negative-price condition driven by 1,648 MW of wind generation against subdued winter morning consumption. Wind is supplying more than total demand, with gas (CCGT at 80 MW, OCGT at 0.11 MW) and a negligible battery contribution rounding out the mix. The price-demand relationship across the past 24 hours is stark: when demand climbed to its intraday peak of around 2,009 MW at 18:25 AEST yesterday, prices were firmly positive in the $28–$45/MWh range; as demand retreated through the afternoon and evening toward the current 1,488 MW, prices tracked negative and have held there almost continuously since approximately 03:30 AEST.

The demand trajectory through today's forecast period shows prices remaining negative or near-zero through to around 08:00 AEST (07:00 UTC), before the morning demand ramp pushes them positive. Forecasts indicate a price lift to $7.29/MWh at 08:00 AEST, reaching $15.28/MWh by 08:30 AEST and plateauing in the $17–$18/MWh band from 09:00 through to approximately 16:00 AEST as demand builds through the working day. This is a shallow but sustained positive-price corridor — well below yesterday's morning peak prints of $39–$52/MWh — suggesting the market is not anticipating the same supply tightness. The deep negative price window forecast for 13:00–16:00 AEST (-$20/MWh at 13:00 UTC, -$5 to -$6/MWh across the surrounding intervals) points to a second period of generation surplus once the midday demand trough arrives.

Demand-side context from market notices is relevant here: AEMO issued a Forecast LOR1 for SA on 17 June covering both the 08:00–09:30 AEST and 16:30–22:30 AEST windows, though that notice was subsequently cancelled on 11 June. No active reserve or intervention notices apply to SA today. The weather profile — 12.7°C with moderate wind at 19.8 km/h and zero solar potential at this hour — is consistent with the current heating demand reading of 5.3, but at 1,488 MW total demand, the market is absorbing that load comfortably under present wind output. As solar potential remains low across the day (cloud cover at 65% currently, forecast average of 15.1% tomorrow), wind will remain the primary variable governing whether afternoon prices stay negative or firm toward positive territory during the evening demand ramp.

Flexible load operators have a clear window: negative prices are forecast to persist with only a brief interruption through to 07:30 AEST, with a second negative-price block returning from approximately 19:00 AEST (09:00 UTC) through to at least 04:00 AEST Friday morning, including two forecast prints of -$20/MWh. The morning positive-price corridor of $16–$18/MWh is the day's most actionable constraint boundary for demand response planning.