In January 2022, Britain's electricity averaged 185 gCO₂/kWh, in the moderate band (140–219 g). That is 4% cleaner than December 2021 (192 g), and 16% cleaner than January 2021 (219 g). Gas made 39.4% of the electricity generated, wind 26.4%, nuclear 14.7% and imports 8.1%; low-carbon sources together made 50.6%. The cleanest half hour was 41 g at 04:30 on Monday 3 January, and the dirtiest 319 g at 07:30 on Friday 14 January. The cleanest day was Saturday 1 January (62 g on average); the windiest was Saturday 29 January (51.8% wind).
Carbon intensity, day by day
Day by day, as a table
| Day | gCO₂/kWh | Low-carbon | Wind | Solar | Gas | Half hours |
|---|---|---|---|---|---|---|
| Sat 1 Jan | 62 | – | – | – | – | 48 |
| Sun 2 Jan | 67 | – | – | – | – | 48 |
| Mon 3 Jan | 89 | – | – | – | – | 48 |
| Tue 4 Jan | 113 | 67.5% | 41.2% | 0.1% | 25.0% | 48 |
| Wed 5 Jan | 141 | 61.5% | 33.4% | 1.5% | 30.5% | 48 |
| Thu 6 Jan | 161 | 56.2% | 31.7% | 0.4% | 34.3% | 48 |
| Fri 7 Jan | 137 | 62.2% | 36.9% | 0.7% | 27.1% | 48 |
| Sat 8 Jan | 120 | 66.3% | 40.3% | 0.2% | 21.3% | 48 |
| Sun 9 Jan | 157 | 56.1% | 28.5% | 1.4% | 30.0% | 48 |
| Mon 10 Jan | 225 | 47.8% | 22.7% | 0.2% | 46.8% | 48 |
| Tue 11 Jan | 235 | 45.7% | 20.8% | 0.5% | 48.9% | 48 |
| Wed 12 Jan | 239 | 43.3% | 20.4% | 1.7% | 51.5% | 48 |
| Thu 13 Jan | 237 | 43.5% | 20.1% | 1.8% | 47.8% | 48 |
| Fri 14 Jan | 277 | 33.1% | 6.9% | 1.7% | 53.7% | 48 |
| Sat 15 Jan | 254 | 36.2% | 10.8% | 0.6% | 51.0% | 48 |
| Sun 16 Jan | 174 | 55.2% | 28.7% | 1.1% | 33.5% | 48 |
| Mon 17 Jan | 239 | 41.9% | 17.1% | 1.9% | 45.6% | 48 |
| Tue 18 Jan | 236 | 42.4% | 20.0% | 1.0% | 49.1% | 48 |
| Wed 19 Jan | 167 | 57.2% | 36.9% | 1.2% | 36.9% | 48 |
| Thu 20 Jan | 214 | 46.3% | 25.2% | 1.7% | 45.3% | 48 |
| Fri 21 Jan | 227 | 43.6% | 21.8% | 0.9% | 47.8% | 48 |
| Sat 22 Jan | 208 | 45.1% | 19.9% | 0.9% | 43.6% | 48 |
| Sun 23 Jan | 219 | 44.1% | 18.7% | 0.3% | 43.3% | 48 |
| Mon 24 Jan | 272 | 36.0% | 11.1% | 0.3% | 51.7% | 48 |
| Tue 25 Jan | 283 | 34.9% | 11.4% | 0.2% | 54.1% | 48 |
| Wed 26 Jan | 201 | 54.6% | 31.5% | 1.1% | 36.9% | 48 |
| Thu 27 Jan | 177 | 58.8% | 37.4% | 1.2% | 32.4% | 48 |
| Fri 28 Jan | 199 | 52.4% | 29.5% | 1.0% | 37.6% | 48 |
| Sat 29 Jan | 90 | 74.5% | 51.8% | 1.4% | 15.0% | 48 |
| Sun 30 Jan | 169 | 55.5% | 29.4% | 2.5% | 28.7% | 48 |
| Mon 31 Jan | 133 | 66.5% | 44.8% | 1.8% | 24.2% | 48 |
What powered the grid
Each fuel's average share of the electricity generated in Great Britain in January 2022, with January 2021 beneath it for comparison. Imports count as one source, as NESO counts them.
Hours in each carbon band
- Very low (under 70 g): 66 hours, 9%
- Low (70–139 g): 134 hours, 18%
- Moderate (140–219 g): 264 hours, 35%
- High (220–299 g): 271 hours, 36%
- Very high (300 g or more): 11 hours, 1%
Records in January 2022
- Cleanest half hour
- 41 g 04:30 on Monday 3 January
- Dirtiest half hour
- 319 g 07:30 on Friday 14 January
- Most wind
- 65.3% 05:00 on Saturday 29 January
- Most solar
- 12.0% 12:00 on Sunday 30 January
- Most low-carbon
- 89.5% 04:00 on Wednesday 5 January
- Least gas
- 5.8% 02:00 on Wednesday 5 January
- Cleanest day
- 62 g Saturday 1 January
- Dirtiest day
- 283 g Tuesday 25 January
- Windiest day
- 51.8% wind Saturday 29 January
- Sunniest day
- 2.5% solar Sunday 30 January
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 26 October 2026.