Carbon Forecast: Saturday 23 May 2026

Carbon intensity across the NEM at 06:25 AEST sits at opposite extremes, with Tasmania at 0 tCO2/MWh on 100% renewables (1,005 MW hydro, 109 MW wind) and South Australia at 0.05 tCO2/MWh with 91.7% renewable penetration driven by 1,146 MW of wind and a small gas firming contribution of 103 MW across OCGT and CCGT. These two regions are the clear low-intensity options for carbon-sensitive load scheduling right now. At the other end, Victoria sits at 1.03 tCO2/MWh with just 15.9% renewables — 4,491 MW of brown coal dominates the stack, with 834 MW of wind the only meaningful zero-emissions contributor and no solar or battery output at this hour. Queensland is at 0.74 tCO2/MWh (14.8% renewables), with 4,284 MW of black coal carrying the bulk of the load alongside 256 MW of gas OCGT and 623 MW of wind. NSW sits at 0.66 tCO2/MWh with 24.5% renewables — 4,668 MW of black coal, offset partly by 920 MW of wind and 592 MW of hydro.

The data through the day shows a clear pattern for NSW and QLD: both regions recorded their lowest intensity in the overnight period (roughly 10:00–13:00 AEST), when wind output was running alongside lower demand, before intensity climbed through the morning and afternoon peaks as coal and gas ramped to meet rising load. NSW hit a trough near 0.41 tCO2/MWh around 10:00–12:00 AEST, and QLD dipped to around 0.43 tCO2/MWh at a similar time. Both have since risen steadily into the evening. Victoria followed the same trajectory but at a structurally higher baseline, peaking above 1.03 tCO2/MWh through the morning peak and holding near that level into the evening. SA is the outlier — intensity rose from near zero overnight to around 0.21 tCO2/MWh during the morning as wind softened and gas firmed, then fell back sharply after midday as wind recovered, sitting below 0.05 tCO2/MWh from approximately 17:00 AEST onward.

For carbon-sensitive loads, Tasmania and SA are the optimal dispatch regions at any point today. SA's green window is effectively open now and has been since around 17:00 AEST, with wind sustaining above 1,100 MW and gas firming minimal. Tasmania's 0 tCO2/MWh status is consistent across all intervals in the dataset and is not time-dependent. In NSW and QLD, the next low-intensity window will be overnight tonight into early tomorrow morning — expect intensity to ease back toward the 0.41–0.43 tCO2/MWh range as demand falls and wind output holds. Victoria's intensity is unlikely to fall below 0.85 tCO2/MWh at any point today given the absence of solar at this time of year and brown coal's flat dispatch profile; the marginal improvement window there aligns with lower overnight demand rather than any renewable surge.