UK Electricity Grid Report 2015
In 2015, Great Britain generated 305 TWh of electricity. Gas was the biggest single source at 27.7%. Renewables (wind, solar and hydro) supplied 15%, or 15% counting biomass, and each unit generated averaged 356gCO₂ per kWh. That made 2015 cleaner than 2014: carbon intensity fell 62.8 g on the year.
Automated summaryIn 2015, Great Britain's electricity grid generated 304.7 TWh, with gas the single largest source at 27.7% of the mix, followed by coal at 24.4% and nuclear at 21.6%. Low carbon sources accounted for 36.5% of generation, while renewables including wind, solar, hydro and biomass contributed 15%, with wind alone supplying 7.7%. Coal remained a significant presence throughout the year, with no coal-free hours recorded. The average carbon intensity stood at 355.9 gCO2/kWh.
Renewables share
15%
15% incl. biomass
Low carbon share
36.5%
renewables + nuclear
Carbon intensity
356 g
per kWh · low 140 g, high 532 g
Generation
305 TWh
incl. estimated embedded wind and solar
Coal share
24.4%
no coal-free hours
Peak wind output
6.6 GW
highest half-hour average
The 2015 generation mix, fuel by fuel
share of GB generation- Gas27.7% · 84.31 TWh
- Coal24.4% · 74.5 TWh
- Nuclear21.6% · 65.71 TWh
- Wind7.7% · 23.38 TWh
- Imports7.6% · 23.26 TWh
- Other3.7% · 11.29 TWh
- Solar2.4% · 7.22 TWh
- Hydro1.3% · 4.09 TWh
- Storage0.9% · 2.68 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 2015 compares
- Versus 2014: renewables +3.4 points, carbon intensity -62.8 g.
- Versus 2009, the first year on record: renewables up 11.6 points (from 3.4%), and each unit of electricity 20% cleaner (445 g to 356 g).
- Explore the neighbouring years: 2014 · 2016 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 2015", purelyenergy.co.uk/grid-report/2015. Derived from NESO historic generation mix data.
2015 grid questions, answered
How green was UK electricity in 2015?
In 2015, wind, solar and hydro supplied 15% of GB generation (15% including biomass), low-carbon sources supplied 36.5%, and the average carbon intensity was 356 gCO2 per kWh.
What was the biggest source of UK electricity in 2015?
Gas was the largest single source in 2015, supplying 27.7% of GB generation. The full fuel-by-fuel breakdown is on this page.
How much coal did the UK burn for electricity in 2015?
Coal supplied 24.4% of GB generation in 2015 (74.5 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
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