In February 2026, Britain's electricity averaged 137 gCO₂/kWh, in the low band (70–139 g). That is 6% cleaner than January 2026 (145 g), and 7% cleaner than February 2025 (148 g). Wind made 39.4% of the electricity generated, gas 30.4%, nuclear 11.5% and imports 9.2%; low-carbon sources together made 60.4%. The cleanest half hour was 39 g at 23:30 on Sunday 22 February, and the dirtiest 250 g at 18:00 on Tuesday 17 February. Sunday 22 February was both the cleanest day (55 g on average) and the windiest (59.8% wind).
Carbon intensity, day by day
Day by day, as a table
| Day | gCO₂/kWh | Low-carbon | Wind | Solar | Gas | Half hours |
|---|---|---|---|---|---|---|
| Sun 1 Feb | 161 | 49.1% | 24.1% | 1.4% | 34.0% | 48 |
| Mon 2 Feb | 131 | 65.0% | 43.3% | 0.7% | 27.0% | 48 |
| Tue 3 Feb | 122 | 66.4% | 47.1% | 0.5% | 26.1% | 48 |
| Wed 4 Feb | 150 | 59.7% | 38.0% | 2.4% | 34.1% | 48 |
| Thu 5 Feb | 106 | 70.7% | 53.7% | 0.6% | 23.9% | 48 |
| Fri 6 Feb | 135 | 62.0% | 43.7% | 0.9% | 31.4% | 48 |
| Sat 7 Feb | 141 | 59.2% | 38.2% | 1.2% | 31.8% | 48 |
| Sun 8 Feb | 164 | 53.0% | 29.2% | 1.8% | 37.8% | 48 |
| Mon 9 Feb | 184 | 49.7% | 28.5% | 1.4% | 44.2% | 48 |
| Tue 10 Feb | 164 | 54.8% | 34.3% | 0.9% | 38.6% | 48 |
| Wed 11 Feb | 165 | 53.7% | 32.2% | 1.6% | 38.3% | 48 |
| Thu 12 Feb | 169 | 51.7% | 29.9% | 1.5% | 38.7% | 48 |
| Fri 13 Feb | 185 | 49.1% | 28.7% | 1.7% | 44.3% | 48 |
| Sat 14 Feb | 195 | 46.0% | 21.5% | 5.5% | 46.7% | 48 |
| Sun 15 Feb | 108 | 68.3% | 47.8% | 1.2% | 23.2% | 48 |
| Mon 16 Feb | 116 | 66.0% | 45.3% | 3.4% | 25.4% | 48 |
| Tue 17 Feb | 165 | 53.8% | 32.2% | 3.8% | 38.2% | 48 |
| Wed 18 Feb | 116 | 66.8% | 47.8% | 1.2% | 25.3% | 48 |
| Thu 19 Feb | 179 | 51.0% | 31.8% | 1.1% | 40.1% | 48 |
| Fri 20 Feb | 118 | 67.6% | 47.6% | 1.7% | 25.0% | 48 |
| Sat 21 Feb | 73 | 75.0% | 55.5% | 2.6% | 12.9% | 48 |
| Sun 22 Feb | 55 | 79.8% | 59.8% | 4.3% | 9.4% | 48 |
| Mon 23 Feb | 102 | 67.9% | 49.8% | 2.6% | 21.3% | 48 |
| Tue 24 Feb | 133 | 59.7% | 39.1% | 4.6% | 32.0% | 48 |
| Wed 25 Feb | 125 | 60.9% | 40.4% | 4.4% | 28.7% | 48 |
| Thu 26 Feb | 64 | 78.6% | 59.2% | 1.6% | 9.9% | 48 |
| Fri 27 Feb | 152 | 52.5% | 29.2% | 2.7% | 32.5% | 48 |
| Sat 28 Feb | 147 | 53.2% | 25.8% | 5.2% | 30.5% | 48 |
What powered the grid
Each fuel's average share of the electricity generated in Great Britain in February 2026, with February 2025 beneath it for comparison. Imports count as one source, as NESO counts them.
Hours in each carbon band
- Very low (under 70 g): 82 hours, 12%
- Low (70–139 g): 249 hours, 37%
- Moderate (140–219 g): 322 hours, 48%
- High (220–299 g): 20 hours, 3%
Records in February 2026
- Cleanest half hour
- 39 g 23:30 on Sunday 22 February
- Dirtiest half hour
- 250 g 18:00 on Tuesday 17 February
- Most wind
- 68.0% 04:30 on Monday 23 February
- Most solar
- 25.0% 11:30 on Saturday 14 February
- Most low-carbon
- 86.0% 04:30 on Monday 23 February
- Least gas
- 5.8% 10:00 on Thursday 26 February
- Cleanest day
- 55 g Sunday 22 February
- Dirtiest day
- 195 g Saturday 14 February
- Windiest day
- 59.8% wind Sunday 22 February
- Sunniest day
- 5.5% solar Saturday 14 February
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 18 October 2026.