UK Electricity Grid Report 2023
In 2023, Great Britain generated 275 TWh of electricity. Gas was the biggest single source at 31.6%. Renewables (wind, solar and hydro) supplied 35.5%, or 40.3% counting biomass, and each unit generated averaged 149gCO₂ per kWh. That made 2023 cleaner than 2022: carbon intensity fell 32.1 g on the year.
Automated summaryIn 2023, Great Britain's electricity grid generated 274.6 TWh, with low carbon sources accounting for 54.3% of the mix and renewables (wind, solar and hydro) contributing 35.5%, rising to 40.3% when biomass is included. Gas remained the largest single source at 31.6%, followed by wind at 23.1% and nuclear at 13.9%, while coal fell to just 1% across a record 4,282 coal-free hours. Average carbon intensity stood at 149 gCO2/kWh, reflecting the continued shift towards cleaner generation. On the market side, the average wholesale price was £96.71/MWh with 214 negative-price hours, while national demand reached 227.9 TWh and peaked at 44 GW in a single half hour.
Renewables share
35.5%
40.3% incl. biomass
Low carbon share
54.3%
renewables + nuclear
Carbon intensity
149 g
per kWh · low 27 g, high 310 g
Generation
275 TWh
incl. estimated embedded wind and solar
Coal share
1%
4,282 coal-free hours
Peak wind output
17.4 GW
highest half-hour average
The 2023 generation mix, fuel by fuel
share of GB generation- Gas31.6% · 86.71 TWh
- Wind23.1% · 63.42 TWh
- Nuclear13.9% · 38.3 TWh
- Imports12.2% · 33.5 TWh
- Solar4.9% · 13.55 TWh
- Biomass4.9% · 13.36 TWh
- Hydro1.2% · 3.25 TWh
- Coal1% · 2.76 TWh
- Other0.9% · 2.57 TWh
- Storage0.6% · 1.66 TWh
Wholesale prices in 2023
market index (MID), volume-weighted across APX and N2EXThe average UK wholesale electricity price in 2023 was £96.71 per MWh on the market index (MID) basis. Prices were negative for 214 hours across the year. The most expensive half hour came on 7 March 2023 (settlement period 38) at £580.38 per MWh; the cheapest, £-77.29, came on 25 September 2023.
Average price
£96.71
per MWh, volume-weighted
Highest half hour
£580
7 March 2023, period 38
Lowest half hour
£-77.29
25 September 2023
Negative price hours
214
price below £0/MWh
Electricity demand in 2023
GB initial national demand outturn (INDO/INDOD), ElexonGreat Britain used 227.9 TWh of electricity in 2023. The hungriest day was 1 December 2023 (862.1 GWh); the quietest, 2 July 2023 (425.2 GWh). Demand peaked at 44 GW on 23 January 2023 (settlement period 36).
Total demand
227.9 TWh
national demand outturn
Peak half hour
44 GW
23 January 2023
Highest day
862.1 GWh
1 December 2023
Quietest day
425.2 GWh
2 July 2023
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 2023 compares
- Versus 2022: renewables +2.5 points, carbon intensity -32.1 g.
- Versus 2009, the first year on record: renewables up 32.1 points (from 3.4%), and each unit of electricity 66.5% cleaner (445 g to 149 g).
- Explore the neighbouring years: 2022 · 2024 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 2023", purelyenergy.co.uk/grid-report/2023. Derived from NESO historic generation mix data.
2023 grid questions, answered
How green was UK electricity in 2023?
In 2023, wind, solar and hydro supplied 35.5% of GB generation (40.3% including biomass), low-carbon sources supplied 54.3%, and the average carbon intensity was 149 gCO2 per kWh.
What was the biggest source of UK electricity in 2023?
Gas was the largest single source in 2023, supplying 31.6% of GB generation. The full fuel-by-fuel breakdown is on this page.
How much coal did the UK burn for electricity in 2023?
Coal supplied 1% of GB generation in 2023 (2.76 TWh), and the grid ran coal-free for 4,282 hours.
What was the average UK wholesale electricity price in 2023?
The average UK wholesale electricity price in 2023 was £96.71 per MWh on the market index (MID) basis, volume-weighted across the year's half-hourly trading.
How many hours were UK power prices negative in 2023?
UK wholesale power prices (market index basis) were negative for 214 hours in 2023.
How much electricity did Great Britain use in 2023?
Great Britain used 227.9 TWh of electricity in 2023, on the national demand outturn basis (Elexon INDOD).
What was GB peak electricity demand in 2023?
GB electricity demand peaked at 44 GW in 2023, on 23 January 2023 (settlement period 36), on the national demand outturn basis.
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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