In April 2022, Britain's electricity averaged 181 gCO₂/kWh, in the moderate band (140–219 g). That is 3% cleaner than March 2022 (186 g), and 10% cleaner than April 2021 (200 g). Gas made 40.3% of the electricity generated, wind 24.1%, nuclear 17.9% and solar 5.3%; low-carbon sources together made 53.9%. The cleanest half hour was 40 g at 13:30 on Saturday 23 April, and the dirtiest 293 g at 19:30 on Saturday 2 April. Saturday 23 April was both the cleanest day (67 g on average) and the windiest (51.3% wind).
Carbon intensity, day by day
Day by day, as a table
| Day | gCO₂/kWh | Low-carbon | Wind | Solar | Gas | Half hours |
|---|---|---|---|---|---|---|
| Fri 1 Apr | 206 | 49.6% | 23.5% | 4.8% | 40.9% | 48 |
| Sat 2 Apr | 259 | 35.6% | 7.9% | 5.1% | 53.3% | 48 |
| Sun 3 Apr | 204 | 49.2% | 20.0% | 4.9% | 43.4% | 48 |
| Mon 4 Apr | 131 | 68.3% | 45.0% | 1.7% | 24.7% | 48 |
| Tue 5 Apr | 130 | 66.7% | 41.1% | 2.8% | 25.2% | 48 |
| Wed 6 Apr | 109 | 71.5% | 46.7% | 3.3% | 19.6% | 48 |
| Thu 7 Apr | 112 | 71.6% | 46.8% | 4.5% | 19.3% | 48 |
| Fri 8 Apr | 188 | 53.0% | 26.7% | 4.9% | 39.5% | 48 |
| Sat 9 Apr | 173 | 55.0% | 25.4% | 6.8% | 33.5% | 48 |
| Sun 10 Apr | 212 | 41.0% | 9.3% | 7.0% | 45.7% | 48 |
| Mon 11 Apr | 120 | 66.4% | 38.7% | 4.8% | 24.9% | 48 |
| Tue 12 Apr | 182 | 53.4% | 28.8% | 2.5% | 39.3% | 48 |
| Wed 13 Apr | 217 | 46.0% | 18.0% | 3.5% | 49.3% | 48 |
| Thu 14 Apr | 254 | 36.2% | 5.7% | 4.4% | 58.2% | 48 |
| Fri 15 Apr | 198 | 49.6% | 15.3% | 6.4% | 48.8% | 48 |
| Sat 16 Apr | 120 | 66.6% | 26.5% | 7.9% | 26.5% | 48 |
| Sun 17 Apr | 90 | 74.1% | 32.4% | 7.6% | 18.2% | 48 |
| Mon 18 Apr | 150 | 60.9% | 21.2% | 7.0% | 34.4% | 48 |
| Tue 19 Apr | 244 | 39.4% | 9.7% | 5.1% | 57.3% | 48 |
| Wed 20 Apr | 213 | 47.1% | 16.9% | 7.0% | 51.3% | 48 |
| Thu 21 Apr | 177 | 55.9% | 26.3% | 7.3% | 42.0% | 48 |
| Fri 22 Apr | 136 | 64.2% | 41.4% | 4.6% | 33.6% | 48 |
| Sat 23 Apr | 67 | 78.4% | 51.3% | 5.8% | 14.7% | 48 |
| Sun 24 Apr | 96 | 72.3% | 40.6% | 8.1% | 21.4% | 48 |
| Mon 25 Apr | 216 | 46.8% | 15.4% | 5.1% | 50.7% | 48 |
| Tue 26 Apr | 239 | 41.7% | 10.3% | 5.8% | 57.1% | 48 |
| Wed 27 Apr | 240 | 40.1% | 9.3% | 4.0% | 57.3% | 48 |
| Thu 28 Apr | 254 | 37.2% | 6.3% | 4.0% | 58.8% | 48 |
| Fri 29 Apr | 254 | 36.8% | 5.8% | 5.6% | 61.7% | 48 |
| Sat 30 Apr | 235 | 41.5% | 10.7% | 7.0% | 58.1% | 48 |
What powered the grid
Each fuel's average share of the electricity generated in Great Britain in April 2022, with April 2021 beneath it for comparison. Imports count as one source, as NESO counts them.
Hours in each carbon band
- Very low (under 70 g): 33 hours, 5%
- Low (70–139 g): 190 hours, 26%
- Moderate (140–219 g): 223 hours, 31%
- High (220–299 g): 274 hours, 38%
Records in April 2022
- Cleanest half hour
- 40 g 13:30 on Saturday 23 April
- Dirtiest half hour
- 293 g 19:30 on Saturday 2 April
- Most wind
- 57.4% 04:30 on Thursday 7 April
- Most solar
- 24.9% 13:00 on Saturday 16 April
- Most low-carbon
- 86.7% 13:30 on Saturday 23 April
- Least gas
- 7.1% 15:00 on Sunday 17 April
- Cleanest day
- 67 g Saturday 23 April
- Dirtiest day
- 259 g Saturday 2 April
- Windiest day
- 51.3% wind Saturday 23 April
- Sunniest day
- 8.1% solar Sunday 24 April
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.