Carbon Forecast: Saturday 5 September 2026

South Australia holds the lowest carbon intensity in the NEM this morning at 0.047 tCO2/MWh with renewable penetration at 90.4%, running almost entirely on wind and battery output with negligible gas (0.1 MW OCGT). Tasmania sits second-lowest at 0.107 tCO2/MWh on 83.5% renewables, hydro-dominant at 554 MW against 124 MW of gas peaking. At the other end, Victoria currently shows 0.799 tCO2/MWh with renewables at 34.6%, and Queensland is close behind at 0.771 tCO2/MWh with renewables down at just 11.9% — both regions leaning heavily on brown and black coal respectively (3831 MW and 4869 MW) as wind output has eased into the evening. NSW sits mid-pack at 0.597 tCO2/MWh with 32% renewables, black coal generation of 3993 MW dominating against 1471 MW of wind.

The current data reflects the tail end of Saturday evening trade (20:30 AEST readings), with VIC and QLD intensities climbing sharply through the evening peak as wind contribution fades and coal ramps to cover demand — VIC intensity rose from 0.541 tCO2/MWh at 07:05 AEST to 0.799 tCO2/MWh by 20:30, tracking the inverse of its renewable share falling from 55.7% to 34.6%. QLD shows the same pattern, intensity climbing from 0.472 tCO2/MWh near dawn to 0.771 tCO2/MWh by evening as renewable share collapsed from 46% to under 12%. NSW mirrored this trajectory, though less severely, moving from a low near 0.333–0.351 tCO2/MWh in the early hours to 0.597 tCO2/MWh at day's end.

For today, expect NSW, VIC and QLD to retrace this diurnal pattern: intensity troughs typically form in the early hours (00:00–04:30 AEST) as overnight wind generation peaks and demand is low, with NSW historically bottoming near 0.33–0.35 tCO2/MWh and VIC near 0.49–0.53 tCO2/MWh in that window. Solar contribution has been minimal to date in this data (NSW and VIC show near-zero solar even at midday, likely a seasonal/weather effect), so the midday green window that typically features on sunnier days is muted this cycle — carbon-sensitive loads in NSW and VIC should prioritise the pre-dawn window instead. QLD's low-renewable profile persisted all day with no clear green window, intensity staying above 0.60 tCO2/MWh for most of the past 24 hours. SA and TAS remain consistently low-carbon throughout, with SA's best windows around 11:00–14:00 AEST (intensity near 0.015–0.019 tCO2/MWh) when wind and battery dispatch peaked — these two regions are the standing low-carbon options for flexible load today regardless of time of day.