Regional Outlook — SA1: Thursday 3 September 2026
**South Australia regional outlook — 4 September 2026, 6:30am AEST**
The SA spot price sits at $86.44/MWh, down sharply from the $150-197/MWh band that held through late morning and early afternoon yesterday. The region has swung wide over the past 24 hours: prices dipped negative overnight (as low as -$20/MWh between 10am-3pm AEST as low demand met strong wind output), then spiked into triple digits from late afternoon into evening as demand climbed above 1,700 MW and wind generation eased off. Current demand reads 1,388 MW, mid-range for the day's 950-1,810 MW envelope.
Generation mix at the latest interval is wind-dominated: 1,220 MW of wind against 232 MW GAS_CCGT, 166 MW GAS_OCGT, 1.6 MW battery, and negligible solar (overnight period). Renewable penetration sits at 75.4%, with carbon intensity at 0.137 tCO2/MWh — both figures reflect the current high-wind, no-solar window. This is a marked improvement on the middle of yesterday, when renewable share fell to 16-28% and carbon intensity peaked near 0.48 tCO2/MWh as wind dropped out and gas-fired plant (including OCGT peaking units) covered the afternoon demand ramp.
Predispatch forecasts point to continued volatility through the day. AEMO's forecast trajectory shows a brief firming to $196.50/MWh around 7am, easing to $101/MWh by 7:30am, then a spike to $147.79/MWh near 8am before collapsing through negative territory from mid-morning: forecasts show -$1 to -$8.60/MWh persisting from roughly 10:30am through to 6pm AEST, consistent with the wind and mild solar contribution flagged in today's weather outlook (solar potential only 1.6, wind potential 6.3). Traders with flexible load should note the identified low-price windows between 2:30am and 7:30am tomorrow, averaging -$4.59 to -$7.85/MWh, offering $200+/MWh savings versus peak.
On notices: AEMO issued and then cancelled a foreseeable intervention event in SA for voltage support on 3 September (Market Notices 144972/144985), alongside a direction to AGL's Torrens Island B4 unit that was subsequently cancelled (144986). A negative settlement residue constraint on the VIC-SA interconnector (NRM_VIC1_SA1) activated and deactivated twice yesterday, reflecting periods of high negative-price flow into SA. No active SA-specific constraints remain in force at time of writing, though the pattern of recurring voltage-related interventions this week warrants attention for engineers managing synchronous generation commitments over the low-demand midday period.