Regional Outlook — SA1 — Monday 4 May 2026

The SA spot price sits at $103.44/MWh at 06:05 AEST, with demand at 1,418 MW. This is a markedly elevated level relative to the overnight period, where prices ran persistently negative — reaching as low as -$10.84/MWh during the pre-dawn window (roughly 15:45–16:00 AEST) — before climbing sharply from 17:00 AEST onwards as solar output dropped to zero and evening demand built. The daytime trading period (08:00–15:00 AEST) was characterised by frequent spikes to $105.08/MWh and one print at $117.16/MWh at 00:20 AEST, with gas plant setting price across most intervals. The 24-hour price profile shows a clear two-regime structure: sustained negative or near-zero prices for roughly 10 hours through the middle of the day/early morning AEST, and consistently elevated prices above $40/MWh — and frequently above $98/MWh — through the morning peak and into tonight.

The current generation mix (06:00 AEST trading interval) comprises gas CCGT at 184 MW, wind at 88 MW, and gas OCGT at 81 MW, with solar contributing 0 MW. Total identified dispatch is 353 MW against a regional demand of around 1,418 MW, indicating substantial import reliance via the Heywood interconnector from Victoria. Renewable penetration sits at just 24.88% at this interval, down sharply from a peak of 87.82% recorded during the early afternoon AEST hours when wind was generating strongly and demand was lower. Carbon intensity is 0.4047 tCO2/MWh — the highest reading in the 24-hour dataset and consistent with the near-total absence of solar and low wind output at this time of night. Temperatures are 13.5°C with full cloud cover and a moderate heating demand signal, conditions that are typical for Adelaide in early May and that are sustaining the elevated demand profile.

Predispatch forecasts signal prices are unlikely to ease materially through the remainder of the night. The 07:00 AEST half-hour is forecast at $122.88/MWh (most recent run), the 08:00 AEST half-hour at $138/MWh, and forecasts for the 09:00–10:30 AEST window range from $138/MWh to $209/MWh across multiple predispatch runs, with several runs printing above $185/MWh for the 07:30–08:00 AEST window. The spread between predispatch runs is wide, indicating material uncertainty around gas commitment and interconnector flows as the morning demand ramp approaches. Wind potential today is forecast at just 0.5 (out of 1.0) with average cloud cover at 56%, so solar will provide some relief from mid-morning but wind is unlikely to suppress prices as it did through yesterday's midday period.

The one active market notice directly relevant to SA and interconnected flows is Notice 144047, issued at 02:30 AEST today, confirming an unplanned outage of Leg 3 of the Directlink interconnector (NSW–QLD), with constraint set N-MBTE_1 invoked. While Directlink does not directly connect SA, any tightening of NEM-wide transfer capacity affects the ability of interstate generation to arbitrage into SA via Victoria