Carbon Forecast — Tuesday 5 May 2026

Tasmania sits at 0.00 tCO2/MWh with 100% renewable generation — 255 MW of wind and 406 MW of hydro — and has maintained that position across every interval in today's dataset. South Australia is the next lowest at 0.448 tCO2/MWh with 16.6% renewables, a mix of 106 MW wind, backed by 377 MW gas CCGT and 157 MW gas OCGT. NSW sits at 0.766 tCO2/MWh with renewables at just 12.9% — 6,197 MW of black coal dominates the stack, with 85 MW wind and 814 MW hydro providing modest offset. Queensland is at 0.858 tCO2/MWh with renewable penetration of only 2.5%, driven almost entirely by 2,507 MW of black coal and negligible solar and hydro at this hour. Victoria is the highest of the mainland regions at 0.903 tCO2/MWh, with 1,652 MW of brown coal forming the base, supplemented by 449 MW wind and 111 MW hydro, giving 24.5% renewables but a stubbornly high intensity floor set by brown coal's emission factor.

Today's trajectory reflects a May overnight and early-morning profile: solar across all mainland regions is currently zero, so the generation mix is weighted heavily toward thermal and hydro. NSW intensity has tracked in a narrow band of 0.73–0.80 tCO2/MWh through the day, with its lowest readings — around 0.724 tCO2/MWh — occurring in the pre-dawn window around 06:55 AEST when wind was marginally stronger. Victoria has been volatile, spiking to 1.027 tCO2/MWh at 23:55 AEST before easing back; its current 0.903 tCO2/MWh remains elevated. Queensland has shown little variation all day, holding between 0.843 and 0.858 tCO2/MWh since mid-morning with wind contribution below 3% throughout. SA has oscillated more, touching a low of 0.325 tCO2/MWh in the 09:30 AEST window when wind penetration reached 34%, but has since settled in the 0.41–0.45 tCO2/MWh range as wind eases into the evening.

For carbon-sensitive loads, the green windows today are region-specific. Tasmania offers a continuous zero-intensity opportunity and is the clear choice for flexible loads that can access the Basslink interconnector. In SA, the earlier wind-driven dip to 0.33 tCO2/MWh has passed; intensity is now rising gently as wind output moderates into the evening, so the next favourable window will depend on overnight wind recovery — watch the 21:00–23:00 AEST period where SA has previously shown improvement when wind picks up. On the mainland, NSW offers the lowest intensity among the coal-heavy regions and its overnight trough — typically 0.73–0.74 tCO2/MWh — may return in the early hours of Thursday as demand eases. With no solar available until after 07:00 AEST tomorrow, and May days shortening, solar-driven intensity improvements on the mainland will be modest; wind variability will be the primary lever through tonight.