Carbon Forecast: Wednesday 27 May 2026

Tasmania sits at 0.00 tCO₂/MWh with 100% renewable penetration — hydro at 1,171 MW and wind at 14 MW covering the entire regional load at 06:30 AEST. NSW is next at 0.59 tCO₂/MWh with 31.6% renewables, where wind (1,267 MW) and hydro (1,226 MW) are displacing a portion of black coal's 5,434 MW base. SA comes in at 0.52 tCO₂/MWh with only 9.1% renewables — wind is producing just 92 MW against a combined gas OCGT/CCGT stack of 954 MW, so the relatively modest intensity reflects gas efficiency rather than renewable volume. QLD sits at 0.73 tCO₂/MWh (14.0% renewables), driven by 4,952 MW of black coal and 713 MW of gas OCGT with wind contributing 684 MW. Victoria is the highest-intensity region at 1.13 tCO₂/MWh with renewable penetration of just 2.5% — brown coal is running at 4,731 MW, wind output is only 131 MW, and solar is negligible at 0.5 MW.

The trend data through today reveals a consistent pattern: intensity across all mainland regions is lowest in the pre-dawn wind window (roughly 01:00–04:00 AEST), lifts into the morning shoulder as demand increases without solar contribution, then peaks through the business hours of 11:00–17:00 AEST before easing again as evening wind picks up. NSW has shown a clear downward track from 0.68 tCO₂/MWh at 07:00 AEST to 0.59 tCO₂/MWh at 06:30 AEST, with renewables climbing from 20% to above 31%. Victoria has moved in the opposite direction — intensity has risen from around 1.00 tCO₂/MWh at the start of the day to a peak of 1.15 tCO₂/MWh mid-evening as wind output collapsed to near zero and brown coal held firm across the demand profile.

For carbon-sensitive loads, the lowest-intensity windows across the NEM today are Tasmania (continuously), NSW from approximately 06:00–08:00 AEST as wind and hydro hold above 30% penetration, and SA in the overnight period when wind was contributing above 30%. The window for mainland low-intensity scheduling has largely passed for today — the evening demand peak between 17:00 and 20:00 AEST is producing elevated intensities across NSW, VIC, SA, and QLD simultaneously. Operators with flexible load in NSW or SA should note that overnight tonight (post-22:00 AEST) is the next viable window, contingent on wind output sustaining current trajectories. Victoria's intensity is unlikely to drop materially until a significant wind event increases output well above its current 131 MW.