This section of the website carries real time and historic data for electricity supply in Britain.
Fuel Mix indicates the different types of generating sources used to supply electricity. Different fuel types cause different amounts of CO2 (equivalent) to be released into the atmosphere and Carbon Intensity indicates the level of CO2 per unit of electricity resulting from any fuel mix.
The data in this section of the website is drawn from a number of sources, with permission and as credited on each page.
Some carbon intensity data is supplied by National Grid, elsewhere it is calculated by ElectricityInfo, see our methodology.
Data on different pages is not always directly comparable as what is being measured can be slightly different. Not all fuel mix and carbon intensity data includes embedded energy — electricity generating plant connected to a distribution network rather than the transmission network, which includes most solar output and a significant amount of total wind output — and interconnector imports are not always included. See the notes on each page for details.
Various approximations and simplifications are necessarily involved in producing the data, particularly as most of it is real-time or near real-time.
We give no guarantee on the availability or accuracy of data provided on this site.