UK Electricity Grid Report 2012
In 2012, Great Britain generated 324 TWh of electricity. Coal was the biggest single source at 42.4%. Renewables (wind, solar and hydro) supplied 6.7%, or 6.7% counting biomass, and each unit generated averaged 505gCO₂ per kWh. Carbon intensity rose 54.9 g on 2011, one of the occasional backwards steps in an otherwise falling series.
Automated summaryIn 2012, coal remained the backbone of Great Britain's electricity grid, accounting for 42.4% of generation and contributing to an average carbon intensity of 504.6 gCO2/kWh, with no coal-free hours recorded across the year. Gas was the second largest source at 25.7%, followed by nuclear at 20.4%, while renewables comprising wind, solar and hydro made up 6.7% of the total. Wind alone contributed 3.9%, and low carbon sources collectively reached 27.1%. Total generation for the year stood at 323.78 TWh.
Renewables share
6.7%
6.7% incl. biomass
Low carbon share
27.1%
renewables + nuclear
Carbon intensity
505 g
per kWh · low 289 g, high 644 g
Generation
324 TWh
incl. estimated embedded wind and solar
Coal share
42.4%
no coal-free hours
Peak wind output
4.9 GW
highest half-hour average
The 2012 generation mix, fuel by fuel
share of GB generation- Coal42.4% · 137.17 TWh
- Gas25.7% · 83.07 TWh
- Nuclear20.4% · 66.02 TWh
- Imports4.2% · 13.73 TWh
- Wind3.9% · 12.61 TWh
- Hydro1% · 3.27 TWh
- Storage0.9% · 2.91 TWh
- Other0.6% · 2.09 TWh
Electricity supplied, 2009 to 2026
TWh per year, generation basis incl. estimated embedded wind and solar- 2009329 TWh
- 2010335 TWh
- 2011322 TWh
- 2012324 TWh
- 2013322 TWh
- 2014310 TWh
- 2015305 TWh
- 2016303 TWh
- 2017301 TWh
- 2018298 TWh
- 2019292 TWh
- 2020276 TWh
- 2021285 TWh
- 2022290 TWh
- 2023275 TWh
- 2024281 TWh
- 2025289 TWh
- 2026151 TWh
Britain supplies markedly less electricity than it did in 2009, even as the economy has grown: efficiency, LED lighting and offshored industry all pushed demand down while the mix decarbonised.
How 2012 compares
- Versus 2011: renewables +1 points, carbon intensity +54.9 g.
- Versus 2009, the first year on record: renewables up 3.3 points (from 3.4%), and each unit of electricity -13.4% cleaner (445 g to 505 g).
- Explore the neighbouring years: 2011 · 2013 or the full year-by-year table.
Cite this report
You are welcome to reuse the figures on this page with a link back. Suggested citation:
Purely Energy, "UK Electricity Grid Report 2012", purelyenergy.co.uk/grid-report/2012. Derived from NESO historic generation mix data.
2012 grid questions, answered
How green was UK electricity in 2012?
In 2012, wind, solar and hydro supplied 6.7% of GB generation (6.7% including biomass), low-carbon sources supplied 27.1%, and the average carbon intensity was 505 gCO2 per kWh.
What was the biggest source of UK electricity in 2012?
Coal was the largest single source in 2012, supplying 42.4% of GB generation. The full fuel-by-fuel breakdown is on this page.
How much coal did the UK burn for electricity in 2012?
Coal supplied 42.4% of GB generation in 2012 (137.17 TWh), and the grid ran coal-free for 0 hours.
Use the data
Every figure on this page, as a CSV you can drop into a spreadsheet.
Basis: NESO historic generation mix (GB transmission generation plus estimated embedded wind and solar), aggregated by calendar year, energy-weighted. Renewables is NESO's wind + solar + hydro measure; the biomass-inclusive share is shown alongside. See the live version of this data on our real-time grid map and today's prices on wholesale market data.
Data comes from the Elexon Insights Solution (BMRS), the NESO Data Portal and the Carbon Intensity API, a project by the National Energy System Operator and the University of Oxford Department of Computer Science. Contains BMRS data © Elexon Limited copyright and database right 2026.
Energy decisions for the grid of 2026
The mix above sets the shape of wholesale prices. We turn it into procurement strategy for businesses across the UK, from fixed contracts to flexible purchasing.
Request a quote and callback