When is electricity cleanest where you live?
Finding the cleanest two hours left today.
See your area
Regional times, not the national average.
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Generation mix
The latest half hour, including rooftop panels and small local wind and solar farms.
- Carbon Intensity API generation mix for the latest complete half hour, which includes NESO's estimate of wind and solar on local networks.
Where the carbon comes from
Each source's share of the electricity in the latest half hour, against its share of the emissions.
- Generation mix and national intensity: Carbon Intensity API, for the same half hour (the latest complete one). The intensity is the measured figure once published, the forecast until then.
- Emission factors: Carbon Intensity API (NESO and partners), grams of CO₂ per kWh. Gas uses the combined-cycle factor.
- Imports are the balance of the published national intensity after domestic sources, because factors are not published for every connected country.
Power flow
Where Britain's power is coming from and going to, from the latest five-minute reading.
- Elexon BMRS FUELINST, latest five-minute reading: transmission generation, pumped storage and interconnectors.
- NESO embedded wind and solar for the current half hour: its forecast until actuals are published. If NESO is late, its last value is carried forward for up to two hours and marked.
- Use in Great Britain is the balance: supply less exports and storage charging. Battery storage is not reported separately.
Grid frequency
Falls below 50 Hz when demand runs ahead, rises above it when generation does.
- Elexon BMRS system frequency: 15-second readings, published in batches about every two minutes; last hour shown.
- NESO keeps frequency within 49.8 to 50.2 Hz in normal running; the legal limits are 49.5 and 50.5 Hz.
The last 24 hours
- Carbon Intensity API generation mix, half hour by half hour.
Across the regions
Carbon intensity for each of the 14 network areas this half hour.
- Carbon Intensity API regional forecast for the current half hour (regional figures are forecasts only).
- Boundaries: NESO, GB DNO licence areas (2024).
From this week's data
All insightsMidday was the cleanest time to use power in GB last week
Generation
The average carbon intensity for GB was 129 g/kWh last week. Wind provided the largest share of the generation mix at 33.7%.
Midday offered the cheapest and cleanest power in London
Tariffs
Agile prices in London reached a low of 5.94p/kWh during the day on Sunday 4 October. Carbon intensity was also lowest during the midday period.