Commodity Demand — SA1: Monday 25 May 2026

South Australia is sitting at 1,458 MW and $257.83/MWh at the 06:30 AEST interval, a sharp contrast to the overnight trough of around 1,082 MW reached at approximately 01:30 AEST when prices held in the $97–$105/MWh range. The price sensitivity to demand changes across the past 12 hours has been pronounced: the morning ramp from roughly 1,130 MW at 01:30 AEST to the day's peak of approximately 2,037 MW at 08:25 AEST drove prices into the $138–$203/MWh band, with multiple spikes above $200/MWh as gas OCGT and CCGT units were called on to meet rising load. With solar generation at 0 MW and wind contributing only 128 MW against a gas fleet running 853 MW combined, the price floor is firmly set by dispatchable thermal plant — leaving the market exposed to any supply-side tightness.

Demand has now fallen from the morning peak back to 1,458 MW as commercial and industrial load winds down through the late afternoon AEST, but prices have not eased proportionally. The $257.83/MWh current price is elevated relative to demand because this interval sits within the evening pre-ramp window when batteries discharge and gas generators are bidding scarcity into tightening supply stacks. Forecasts for the 07:00 AEST target interval (21:00 UTC) cluster around $138–$204/MWh across the most recent pre-dispatch runs, a meaningful step down from current spot, indicating the market expects demand to remain contained rather than spike further into the evening. The wide forecast spread — earlier pre-dispatch runs had targeted as high as $370–$1,001/MWh for this interval before pulling back sharply through the afternoon — reflects genuine uncertainty around the evening demand trajectory and interconnector availability.

Two active market notices are material to today's demand-side picture. The Tailem Bend 275 kV East Bus outage (constraint set S-TB275_E_BUS, active since 24 May) continues to constrain the V-SA interconnector, limiting SA's ability to import from Victoria and amplifying local price sensitivity to demand changes. Additionally, AEMO's planned EMMS production system transfer tonight between 04:00–05:00 AEST (26 May 18:00–19:00 UTC) introduces a narrow window of potential pre-dispatch data latency — traders should note FPP calculations may be delayed during that period. The Murraylink dynamic rating constraint update scheduled for 27 May at 10:00 AEST (constraint equations VSML_RAT_LIM_DYN and SVML_RAT_LIM_DYN) will alter inter-regional transfer modelling in pre-dispatch and PASA from tomorrow, which is relevant for any positions spanning the overnight into Wednesday.

For today's remaining intervals, the demand trajectory points to a modest evening ramp toward 1,500–1,600 MW as heating demand builds in 10.6°C conditions, with no solar contribution and low wind potential at 1.3. Pre-dispatch is pricing the 07:30–08:00 AEST window (21:30–22:00 UTC) in a wide range of $138–$497/MWh depending on the forecast run, underscoring that the evening peak clearing price will be sensitive to whether gas units bid competitively or exercise