Britain's grid since 2020
This site holds a reading of Britain's electricity system for every day since January 2020: what was generated, what it cost, and how much carbon it produced. That is long enough to watch a power system change.
Coal ended on 30 September 2024. On that last day Britain's remaining coal station averaged 179 MW, a rounding error beside the 1,400 MW that was an ordinary day in early 2020, and the 3,400 MW of its highest. Nothing since. The country that opened the world's first coal-fired power station in 1882 stopped burning it for electricity after 142 years, and in the data it simply stops.
Nuclear has quietly fallen by about a third, from an average of around 5,400 MW through 2020 to around 3,600 MW across the past twelve months, as the ageing advanced gas-cooled reactors retire faster than replacements arrive. Both figures are averages over a whole period on purpose: month to month the output swings widely, between roughly 2,900 and 5,200 MW during 2026 alone, so a single month proves very little either way. It is the least discussed line on the chart and one of the largest changes.
Wind now routinely does what nothing else can. The windiest day we hold is 22 December 2024, when wind averaged 21.7 GW across the whole day, more than Britain's entire demand on a mild summer night. The cleanest day was 5 April 2024 at 38 gCO₂/kWh; the dirtiest was 24 January 2020 at 342, nearly nine times higher. Both are in the same run of data.
And prices did something extraordinary. On 28 June 2020, during lockdown, the wholesale price averaged minus £12.54 per MWh: generators paying to keep running because demand had collapsed and it was sunny and windy. Fourteen months later, on 9 September 2021, the same measure averaged £667.65. A spread of £680 per MWh between the two days, little more than a year apart, on a market most people never see.
Why our figure differs from National Grid's
"Electricity used" above includes power generated behind the meter: rooftop solar and small wind on local networks. NESO's published National Demand deliberately excludes that, because to the transmission system a house running on its own solar simply looks like less demand.
Ours runs about 5 GW higher on average, though the gap varies from day to day and is typically somewhere between 3 and 7 GW. Most of it is embedded solar and wind, which averages around 4.3 GW, plus about 1 GW of power stations' own consumption and pumped-storage pumping which National Demand also leaves out. Both figures are correct; they answer different questions. If you are checking us against an official source, that is why they differ.