Carbon Forecast: Saturday 22 August 2026

Tasmania is running at 0.017 tCO2/MWh with 97.4% renewable penetration this morning, the lowest carbon intensity in the NEM, as hydro (1,251 MW) and wind (241 MW) cover almost all demand. South Australia sits second-lowest at 0.242 tCO2/MWh with 62% renewables, supported by 702 MW of wind generation against modest gas output (471 MW combined OCGT/CCGT). At the other end, Victoria is the highest-intensity region at 1.072 tCO2/MWh with renewable penetration down to 10.8%, driven by brown coal (3,857 MW) dominating the mix while wind has dropped to just 112 MW and solar is at zero. Queensland follows at 0.780 tCO2/MWh with 11% renewables, reflecting heavy black coal reliance (5,587 MW) against wind (649 MW). NSW is mid-range at 0.690 tCO2/MWh with 21.5% renewables, with black coal (5,854 MW) and hydro (891 MW) the largest contributors.

The generation mix data points to solar being offline across all regions at this early hour, explaining the elevated intensity readings currently in place — VIC1 and QLD1 in particular show zero or near-zero solar output, leaving coal to carry a larger share of the load. Looking at the trajectory through today, overnight and early morning data from the prior 24 hours shows a clear pattern: intensity troughs across NSW1, VIC1, SA1 and QLD1 typically occur between 00:00 and 05:30 AEST as wind generation peaks and demand is low, with renewable penetration reaching 55-81% in SA1 and 57-60% in NSW1 during those hours. Intensity then climbs sharply from 06:00 as demand ramps and wind typically eases, peaking in the late afternoon/early evening window (15:30-19:30 AEST) before solar contribution fades — VIC1 peaked near 1.14 tCO2/MWh and QLD1 near 0.81 tCO2/MWh in that window yesterday.

For carbon-sensitive loads today, the lowest-intensity window is likely to fall in the early hours before dawn, roughly 00:00-05:30 AEST, particularly in SA1 and NSW1 where overnight wind strength consistently pushed renewable share above 55%. TAS1 remains the standout low-carbon region around the clock regardless of time of day, given its hydro base load. Loads with flexibility should avoid the 16:00-20:00 AEST window in VIC1 and QLD1, where intensity is likely to peak above 1.0 tCO2/MWh and 0.78 tCO2/MWh respectively as coal generation fills the gap left by fading solar and easing wind.