Average grid demand for this UK day.
On 21 September 2025, Britain’s electricity grid averaged 29.40 GW of grid demand, with renewables averaging 71.4% of tracked domestic generation and carbon intensity averaging 74 gCO₂/kWh. Daily UK electricity demand, generation, carbon intensity, imports, exports and key records.
Average grid demand for this UK day.
Highest 15-minute grid demand period.
Average carbon intensity where available.
Average renewable share of tracked generation.
Live Grid Data UK
On 21 September 2025, Britain’s electricity grid averaged 29.40 GW of grid demand, with renewables averaging 71.4% of tracked domestic generation and carbon intensity averaging 74 gCO₂/kWh. Daily UK electricity demand, generation, carbon intensity, imports, exports and key records.
Daily insight
On 21 September 2025, Britain’s electricity grid averaged 29.40 GW of grid demand, with renewables averaging 71.4% of tracked domestic generation and carbon intensity averaging 74 gCO₂/kWh.
The highest demand period was 34.14 GW at 13:00, while the lowest carbon intensity period was 42 gCO₂/kWh at 12:30.
Daily chart
Generation mix