Carbon Forecast: Sunday 13 September 2026

South Australia holds the lowest carbon intensity in the NEM this morning at 0.088 tCO2/MWh with renewable penetration at 84.8%, running on 740 MW wind and minimal gas backfill (142 MW combined OCGT/CCGT). Tasmania sits close behind at 0.074 tCO2/MWh and 88.6% renewables, with hydro (745 MW) doing the bulk of supply alongside 234 MW wind. At the other end, Victoria is currently the highest at 0.804 tCO2/MWh with renewables at just 34.1%, as 3,798 MW of brown coal dominates the mix against 936 MW wind and negligible solar at this hour. NSW (0.606 tCO2/MWh, 30.9% renewable) and Queensland (0.594 tCO2/MWh, 32.1% renewable) sit in between, both still leaning on large black coal fleets (4,675 MW and 4,296 MW respectively).

The overnight-to-morning data shows a clear pattern repeating today: intensity troughs align with overnight wind strength and pre-dawn low demand, then climb sharply from around 06:00-07:00 AEST as coal ramps to meet the morning peak and wind typically eases. NSW and Queensland intensity roughly doubled between 05:00 and 13:00 in the prior 24-hour window (NSW from 0.39 to 0.72 tCO2/MWh, QLD from 0.52 to 0.66 tCO2/MWh), and Victoria showed an even steeper climb, peaking near 0.98 tCO2/MWh in the early evening as brown coal held baseload and wind output fell away. Expect similar shape today: mainland intensities push higher through midday into the evening peak, with Victoria's afternoon-evening window the most carbon-intensive on the grid.

For carbon-sensitive loads, the best windows remain overnight and early morning across NSW, VIC and QLD, roughly 22:00-05:00 AEST, when wind generation and lower demand combine to pull renewable penetration up and intensity down by 30-40% relative to afternoon peaks. South Australia and Tasmania offer consistently low-carbon supply through virtually all hours today, with SA dipping under 0.04 tCO2/MWh in early morning wind troughs and Tasmania holding a tight 0.06-0.13 tCO2/MWh band all day on hydro strength. Loads able to shift consumption toward SA or Tasmania, or to schedule mainland-dependent operations before 06:00 AEST, will see the largest emissions reduction opportunity today.