About and method
About Electricity Live
Electricity Live shows where Great Britain’s electricity comes from, every 5 minutes. It covers the grid of England, Scotland and Wales. Northern Ireland is part of a separate all-island grid with Ireland. People often call this the “National Grid live” mix.
Electricity Live is independent. It has no connection to National Grid, the National Energy System Operator (NESO) or Elexon.
What the figures mean
- Demand
- The power that Great Britain uses at a moment, in gigawatts (GW). Electricity Live calculates it as generation plus transfers. It includes the estimated output of embedded wind and solar.
- Generation
- The power made by power stations and wind and solar farms in Great Britain: nuclear, biomass, hydro, gas, wind and solar.
- Transfers
- The net flow into Great Britain through the interconnectors and pumped storage. A value below zero means that more power goes out than comes in.
- Embedded wind and solar
- Small wind and solar farms connect to the local distribution networks, not to the transmission grid, so the grid operator cannot meter them directly. NESO estimates their output every half hour. Electricity Live adds these estimates to the metered wind figure and uses them for all of solar.
- Interconnectors
- Undersea cables that link Great Britain to France, Belgium, the Netherlands, Denmark, Norway and the island of Ireland. Power flows in either direction, mostly from the cheaper market to the dearer one.
- Pumped storage
- Hydro stations such as Dinorwig and Cruachan pump water uphill when power is cheap, and release it through turbines when demand is high. They show as imports when they generate and as exports when they pump.
- Carbon intensity
- The grams of carbon dioxide emitted for each kilowatt hour of electricity (gCO₂/kWh). The Carbon Intensity API gives the national value every half hour, with an index from very low to very high.
- Price
- The market index price for each half hour, in pounds per megawatt hour (£/MWh), from the Elexon Insights Solution. It is a wholesale price, not the price on a household bill.
- Zero-carbon share
- The share of generation from wind, solar, hydro and nuclear. Biomass is not included, because burning it emits carbon dioxide at the chimney.
Where the data comes from
| Source | Data | Detail |
|---|---|---|
| Elexon Insights Solution | Generation by fuel type and flows through each interconnector (FUELINST). Market index price. | 5 minutes for generation, half-hourly for price |
| NESO Data Portal | Embedded wind and solar estimates (demand data update). Historic generation mix for the yearly chart. | Half-hourly |
| Carbon Intensity API | National carbon intensity and its index, from NESO and the University of Oxford. | Half-hourly |
How the figures are calculated
- The site fetches new data from each source every few minutes and keeps it in its own database.
- Gas is the sum of combined-cycle (CCGT) and open-cycle (OCGT) gas turbines. Wind is the metered wind output plus the embedded wind estimate.
- Demand equals generation plus transfers. Transfers are imports minus exports through the interconnectors, plus the net output of pumped storage.
- Shares in the live view are shares of supply: all power that enters the grid, including imports. Shares in the yearly chart are shares of generation inside Great Britain.
- The live view leaves out coal, oil, battery storage and “other” generation, which Elexon reports separately. Together they are usually a small share of supply.
- Days run from midnight to midnight UK time, so a day has 23 hours when the clocks go forward and 25 when they go back.
- When a source has a gap, the site repeats the last known value until new data arrives.
Downloads
- Annual generation mix (CSV): the share of each source and the average carbon intensity for each year from 2012 to 2026. The latest year is partial.
- Each page in the daily archive has a CSV and a JSON file with the 5-minute data for that day, from 18 July 2026.
- The live data is at
/api/live.json: the last 24 hours at 5-minute steps, and the yearly mix.
Licence and credits
The figures on this site come from these sources. Credit them when you use the figures:
- Contains BMRS data © Elexon Limited copyright and database right 2026.
- Embedded generation estimates and the historic generation mix: NESO, under the NESO Open Data Licence.
- Carbon intensity: the Carbon Intensity API by NESO and the University of Oxford, under CC BY 4.0.
Contact
Electricity Live is made by Twelvebit. For questions about the figures, errors in the data or use of the site, email [email protected].