After last quarter’s role reversal, gas overtook wind again to be the largest source of electricity produced. This was in part driven by low wind speeds, meaning wind farms produced one-sixth less electricity than they did last year, despite capacity growing by 10%.
Nuclear, biomass, hydro and gas power stations all produced around one-fifth less electricity than during the same quarter last year. Various reasons were at play: retirements and outages for refuelling for nuclear, high fuel prices kept biomass plants offline, low rainfall reduced hydro output, and less gas was needed as imports from Europe surged. Solar was the only technology to go against this downwards trend. In June, National Grid updated its estimate of installed solar PV capacity for the first time in 4 years.
Coal power stations registered their lowest ever output over a quarter. At just under 0.1 TWh, this was equivalent to the consumption of a medium-sized town or city such as Blackpool or Worcester. May came very close to being the first ‘zero coal’ month in nearly 3 years. One coal power station operated for a single hour to cover for an unexpected outage in a nuclear plant. Over the month, coal generation averaged less than 1 MW.
1 Other sources give different values because of the types of plant they consider. For example, BEIS Energy Trends records an additional 0.7 GW of hydro, 0.6 GW of biomass and 3 GW of waste-to-energy plants. These plants and their output are not visible to the electricity transmission system and so cannot be reported on here.
2 We include an estimate of the installed capacity of smaller storage devices which are not monitored by the electricity market operator. Britain’s storage capacity is made up of 2.9 GW of pumped hydro storage, 0.6 GW of lithium-ion batteries, 0.4 GW of flywheels and 0.3 GW of compressed air.