In October 2022, Britain's electricity averaged 156 gCO₂/kWh, in the moderate band (140–219 g). That is 26% cleaner than September 2022 (210 g), and 4% dirtier than October 2021 (150 g). Wind made 37.5% of the electricity generated, gas 36.1%, nuclear 14.8% and biomass 3.1%; low-carbon sources together made 60.5%. The cleanest half hour was 47 g at 14:30 on Saturday 1 October, and the dirtiest 290 g at 08:00 on Thursday 13 October. Saturday 1 October was both the cleanest day (74 g on average) and the windiest (55.9% wind).
Carbon intensity, day by day
Day by day, as a table
| Day | gCO₂/kWh | Low-carbon | Wind | Solar | Gas | Half hours |
|---|---|---|---|---|---|---|
| Sat 1 Oct | 74 | 80.0% | 55.9% | 4.9% | 14.8% | 48 |
| Sun 2 Oct | 140 | 62.9% | 35.6% | 5.3% | 30.2% | 48 |
| Mon 3 Oct | 233 | 42.6% | 20.7% | 3.1% | 50.4% | 48 |
| Tue 4 Oct | 144 | 65.6% | 44.8% | 1.4% | 32.0% | 48 |
| Wed 5 Oct | 101 | 74.1% | 51.7% | 1.7% | 21.6% | 48 |
| Thu 6 Oct | 105 | 71.9% | 52.2% | 4.1% | 24.4% | 48 |
| Fri 7 Oct | 86 | 76.6% | 54.3% | 3.1% | 18.6% | 48 |
| Sat 8 Oct | 128 | 64.6% | 35.4% | 5.7% | 28.6% | 48 |
| Sun 9 Oct | 93 | 74.7% | 47.3% | 4.0% | 19.5% | 48 |
| Mon 10 Oct | 129 | 66.8% | 38.9% | 4.7% | 29.3% | 48 |
| Tue 11 Oct | 221 | 44.8% | 17.9% | 3.9% | 49.3% | 48 |
| Wed 12 Oct | 197 | 51.5% | 27.9% | 1.9% | 45.4% | 48 |
| Thu 13 Oct | 244 | 38.5% | 14.7% | 3.5% | 57.7% | 48 |
| Fri 14 Oct | 230 | 44.0% | 19.3% | 1.9% | 53.7% | 48 |
| Sat 15 Oct | 115 | 71.9% | 46.0% | 3.4% | 26.5% | 48 |
| Sun 16 Oct | 107 | 72.3% | 44.9% | 4.1% | 23.4% | 48 |
| Mon 17 Oct | 122 | 70.4% | 47.1% | 3.5% | 28.8% | 48 |
| Tue 18 Oct | 236 | 40.4% | 13.9% | 4.0% | 57.2% | 48 |
| Wed 19 Oct | 156 | 60.3% | 42.1% | 1.9% | 38.8% | 48 |
| Thu 20 Oct | 207 | 48.1% | 29.6% | 1.3% | 49.2% | 48 |
| Fri 21 Oct | 215 | 45.4% | 26.6% | 1.5% | 52.2% | 48 |
| Sat 22 Oct | 179 | 55.0% | 33.6% | 2.6% | 44.2% | 48 |
| Sun 23 Oct | 172 | 53.7% | 30.0% | 1.9% | 43.4% | 48 |
| Mon 24 Oct | 163 | 57.8% | 36.4% | 2.4% | 39.2% | 48 |
| Tue 25 Oct | 193 | 52.4% | 32.0% | 2.4% | 45.8% | 48 |
| Wed 26 Oct | 120 | 70.4% | 51.5% | 2.6% | 27.3% | 48 |
| Thu 27 Oct | 172 | 58.2% | 38.5% | 1.5% | 39.8% | 48 |
| Fri 28 Oct | 144 | 64.3% | 43.3% | 2.6% | 34.6% | 48 |
| Sat 29 Oct | 166 | 58.2% | 35.7% | 1.6% | 38.9% | 48 |
| Sun 30 Oct | 108 | 73.4% | 51.6% | 1.6% | 23.4% | 50 |
| Mon 31 Oct | 137 | 65.4% | 43.9% | 1.8% | 32.0% | 48 |
What powered the grid
Each fuel's average share of the electricity generated in Great Britain in October 2022, with October 2021 beneath it for comparison. Imports count as one source, as NESO counts them.
Hours in each carbon band
- Very low (under 70 g): 65 hours, 9%
- Low (70–139 g): 256 hours, 34%
- Moderate (140–219 g): 277 hours, 37%
- High (220–299 g): 149 hours, 20%
Records in October 2022
- Cleanest half hour
- 47 g 14:30 on Saturday 1 October
- Dirtiest half hour
- 290 g 08:00 on Thursday 13 October
- Most wind
- 66.1% 01:30 on Friday 7 October
- Most solar
- 21.0% 12:30 on Sunday 2 October
- Most low-carbon
- 88.1% 13:30 on Saturday 1 October
- Least gas
- 8.9% 14:30 on Saturday 1 October
- Cleanest day
- 74 g Saturday 1 October
- Dirtiest day
- 244 g Thursday 13 October
- Windiest day
- 55.9% wind Saturday 1 October
- Sunniest day
- 5.7% solar Saturday 8 October
About these figures
GridMonkey records NESO's carbon intensity and generation mix for Great Britain every half hour: the actual figure where NESO has published one, otherwise its forecast. They are added up by UK calendar day and month. Percentages are shares of the electricity generated, imports included, so the fuels add up to 100%. Low-carbon means wind, solar, nuclear, biomass and hydro. The carbon bands are GridMonkey's: very low under 70 g, low 70–139 g, moderate 140–219 g, high 220–299 g and very high 300 g or more, per kWh. Northern Ireland has its own grid and isn't included.
To see the grid now, open GridMonkey. For the wind farms that ran hardest this week, see the wind farm league table.
Data: NESO Carbon Intensity API (carbonintensity.org.uk), licensed under CC BY 4.0, recorded and summarised by GridMonkey. Figures as of 25 October 2026.