How clean the electricity is right now
Carbon intensity is the amount of CO₂ released to produce a unit of electricity. It falls when wind and nuclear dominate the mix, and rises when gas has to fill the gap.
Right now · 01:00–01:30 · forecast, not yet settled
208gCO₂/kWh
High intensity
12% higher than yesterday · 69% higher than a year ago
Cleanest time left today
23:00
73 gCO₂/kWh
A good window for heavy appliances
Cleanest half hour today
73gCO₂/kWh
At 23:00
Dirtiest half hour today
222gCO₂/kWh
At 00:00
Carbon intensity across today
Measured figures where the half hour has settled, alongside the forecast for the whole day.
View as table
| Half hour | Measured | Forecast | Index |
|---|---|---|---|
| 00:00–00:30 | - | 222 | High |
| 00:30–01:00 | - | 216 | High |
| 01:00–01:30 | - | 208 | High |
| 01:30–02:00 | - | 203 | High |
| 02:00–02:30 | - | 196 | High |
| 02:30–03:00 | - | 192 | High |
| 03:00–03:30 | - | 182 | High |
| 03:30–04:00 | - | 173 | High |
| 04:00–04:30 | - | 166 | Moderate |
| 04:30–05:00 | - | 169 | Moderate |
| 05:00–05:30 | - | 178 | High |
| 05:30–06:00 | - | 190 | High |
| 06:00–06:30 | - | 189 | High |
| 06:30–07:00 | - | 186 | High |
| 07:00–07:30 | - | 182 | High |
| 07:30–08:00 | - | 182 | High |
| 08:00–08:30 | - | 178 | High |
| 08:30–09:00 | - | 168 | Moderate |
| 09:00–09:30 | - | 167 | Moderate |
| 09:30–10:00 | - | 168 | Moderate |
| 10:00–10:30 | - | 162 | Moderate |
| 10:30–11:00 | - | 152 | Moderate |
| 11:00–11:30 | - | 141 | Moderate |
| 11:30–12:00 | - | 133 | Moderate |
| 12:00–12:30 | - | 127 | Moderate |
| 12:30–13:00 | - | 120 | Moderate |
| 13:00–13:30 | - | 112 | Moderate |
| 13:30–14:00 | - | 100 | Moderate |
| 14:00–14:30 | - | 89 | Low |
| 14:30–15:00 | - | 88 | Low |
| 15:00–15:30 | - | 86 | Low |
| 15:30–16:00 | - | 89 | Low |
| 16:00–16:30 | - | 90 | Moderate |
| 16:30–17:00 | - | 92 | Moderate |
| 17:00–17:30 | - | 99 | Moderate |
| 17:30–18:00 | - | 104 | Moderate |
| 18:00–18:30 | - | 105 | Moderate |
| 18:30–19:00 | - | 104 | Moderate |
| 19:00–19:30 | - | 101 | Moderate |
| 19:30–20:00 | - | 97 | Moderate |
| 20:00–20:30 | - | 94 | Moderate |
| 20:30–21:00 | - | 89 | Low |
| 21:00–21:30 | - | 82 | Low |
| 21:30–22:00 | - | 77 | Low |
| 22:00–22:30 | - | 78 | Low |
| 22:30–23:00 | - | 77 | Low |
| 23:00–23:30 | - | 73 | Low |
| 23:30–00:00 | - | 73 | Low |
The next 48 hours
Forecast intensity ahead, for planning further out than the end of today.
View as table
| Half hour | Forecast | Band |
|---|---|---|
| Wed 01:00 | 208 | High |
| Wed 01:30 | 203 | High |
| Wed 02:00 | 196 | High |
| Wed 02:30 | 192 | High |
| Wed 03:00 | 182 | High |
| Wed 03:30 | 173 | High |
| Wed 04:00 | 166 | Moderate |
| Wed 04:30 | 169 | Moderate |
| Wed 05:00 | 178 | High |
| Wed 05:30 | 190 | High |
| Wed 06:00 | 189 | High |
| Wed 06:30 | 186 | High |
| Wed 07:00 | 182 | High |
| Wed 07:30 | 182 | High |
| Wed 08:00 | 178 | High |
| Wed 08:30 | 168 | Moderate |
| Wed 09:00 | 167 | Moderate |
| Wed 09:30 | 168 | Moderate |
| Wed 10:00 | 162 | Moderate |
| Wed 10:30 | 152 | Moderate |
| Wed 11:00 | 141 | Moderate |
| Wed 11:30 | 133 | Moderate |
| Wed 12:00 | 127 | Moderate |
| Wed 12:30 | 120 | Moderate |
| Wed 13:00 | 112 | Moderate |
| Wed 13:30 | 100 | Moderate |
| Wed 14:00 | 89 | Low |
| Wed 14:30 | 88 | Low |
| Wed 15:00 | 86 | Low |
| Wed 15:30 | 89 | Low |
| Wed 16:00 | 90 | Moderate |
| Wed 16:30 | 92 | Moderate |
| Wed 17:00 | 99 | Moderate |
| Wed 17:30 | 104 | Moderate |
| Wed 18:00 | 105 | Moderate |
| Wed 18:30 | 104 | Moderate |
| Wed 19:00 | 101 | Moderate |
| Wed 19:30 | 97 | Moderate |
| Wed 20:00 | 94 | Moderate |
| Wed 20:30 | 89 | Low |
| Wed 21:00 | 82 | Low |
| Wed 21:30 | 77 | Low |
| Wed 22:00 | 78 | Low |
| Wed 22:30 | 77 | Low |
| Wed 23:00 | 73 | Low |
| Wed 23:30 | 73 | Low |
| Thu 00:00 | 73 | Low |
| Thu 00:30 | 71 | Low |
| Thu 01:00 | 70 | Low |
| Thu 01:30 | 70 | Low |
| Thu 02:00 | 69 | Low |
| Thu 02:30 | 69 | Low |
| Thu 03:00 | 70 | Low |
| Thu 03:30 | 70 | Low |
| Thu 04:00 | 71 | Low |
| Thu 04:30 | 70 | Low |
| Thu 05:00 | 72 | Low |
| Thu 05:30 | 74 | Low |
| Thu 06:00 | 78 | Low |
| Thu 06:30 | 81 | Low |
| Thu 07:00 | 88 | Low |
| Thu 07:30 | 88 | Low |
| Thu 08:00 | 96 | Moderate |
| Thu 08:30 | 94 | Moderate |
| Thu 09:00 | 93 | Moderate |
| Thu 09:30 | 93 | Moderate |
| Thu 10:00 | 85 | Low |
| Thu 10:30 | 75 | Low |
| Thu 11:00 | 73 | Low |
| Thu 11:30 | 72 | Low |
| Thu 12:00 | 70 | Low |
| Thu 12:30 | 78 | Low |
| Thu 13:00 | 81 | Low |
| Thu 13:30 | 84 | Low |
| Thu 14:00 | 89 | Low |
| Thu 14:30 | 96 | Moderate |
| Thu 15:00 | 104 | Moderate |
| Thu 15:30 | 117 | Moderate |
| Thu 16:00 | 127 | Moderate |
| Thu 16:30 | 139 | Moderate |
| Thu 17:00 | 154 | Moderate |
| Thu 17:30 | 164 | Moderate |
| Thu 18:00 | 172 | High |
| Thu 18:30 | 173 | High |
| Thu 19:00 | 173 | High |
| Thu 19:30 | 166 | Moderate |
| Thu 20:00 | 160 | Moderate |
| Thu 20:30 | 159 | Moderate |
| Thu 21:00 | 152 | Moderate |
| Thu 21:30 | 140 | Moderate |
| Thu 22:00 | 134 | Moderate |
| Thu 22:30 | 119 | Moderate |
| Thu 23:00 | 108 | Moderate |
The cleanest window in the next two days starts Tomorrow at 2:00 AM at 69 gCO₂/kWh. Running a wash, a dishwasher or an EV charge then does the least damage.
What this means
Carbon intensity measures how much CO₂ is released to produce each unit of electricity, in grams per kilowatt-hour. It rises and falls constantly, because the mix of generators running changes with the weather and with demand.
A windy night with strong nuclear output can drop below 50. A still, cold evening that needs every gas plant running can pass 300. The same kettle, boiled at different times of day, can be responsible for several times more emissions - which is what makes shifting flexible use worthwhile.
Figures cover Great Britain and account for imports across the interconnectors. Periods still to come are forecast, so they carry no measured value until the half hour has settled.
Updated at 01:50. This page keeps itself current.