Carbon Forecast: Friday 11 September 2026

South Australia is the standout this morning at 0.019 tCO2/MWh with renewable penetration at 96.2%, running almost entirely on 1,027 MW of wind generation with negligible gas support (0.11 MW OCGT). Tasmania sits second-lowest at 0.067 tCO2/MWh on 89.7% renewables, hydro-dominated at 1,060 MW against 125 MW of gas peaking. At the other end, Victoria carries the highest intensity at 1.005 tCO2/MWh with renewables at just 16.5%, reflecting 3,835 MW of brown coal covering the bulk of demand against 697 MW of wind. NSW (0.654 tCO2/MWh, 25.5% renewable) and Queensland (0.670 tCO2/MWh, 23.5% renewable) sit in between, both leaning on black coal — 5,226 MW and 4,834 MW respectively — with wind contributing 760 MW in NSW and a stronger 1,166 MW in Queensland.

The overnight-to-morning pattern across the mainland regions shows intensity climbing steadily from lows around 03:00-05:00 AEST toward a mid-afternoon peak. NSW troughed near 0.35 tCO2/MWh around 05:00 with renewables at 60% before solar dropped away and demand rose, pushing intensity above 0.68 tCO2/MWh through the afternoon and evening. Victoria's trajectory is more pronounced, rising from ~0.80 tCO2/MWh overnight to above 1.05 tCO2/MWh by late afternoon as its renewable share collapsed to near 11-13% during the 16:30-18:00 window. SA bucks this pattern entirely — intensity dropped sharply from around 0.09-0.25 tCO2/MWh mid-morning to near-zero by 16:00 onward as wind output strengthened into the evening, a signal that SA's wind resource is currently running counter to the typical solar-driven midday low.

For carbon-sensitive loads today, SA remains the standout window virtually around the clock, with intensity holding under 0.02 tCO2/MWh from mid-afternoon through the evening period. Tasmania offers a secondary low-carbon window, particularly stable in the 16:30-20:25 AEST band at 0.067-0.072 tCO2/MWh. NSW's best opportunity sits earlier, in the pre-dawn 03:00-05:30 AEST trough when renewables briefly exceeded 50-60%; that window has since closed for today given the current afternoon/evening climb. Victoria and Queensland offer no comparable low-carbon window this afternoon — both are tracking toward their highest intensity levels of the day as evening demand builds against thinning wind and solar output, so load-shifting strategies should prioritise SA and Tasmania for any discretionary or flexible demand over the remainder of the day.