Electricity generated from renewables almost doubled nuclear as coal fell to a record low in the second quarter of this year, EnAppSys found.
Renewables generated 23.1TWh of power in the second quarter, a rise of 9% compared to generation in Q2 of last year. This is almost double the 12.3TWh produced by nuclear plants in the same period.
The decline in nuclear generation was attributed in part to a period in the middle of June when nine of the 16 active nuclear units suffered an outage, resulting in the generation being down 21% on the levels in the same period last year.
Gas-fired plants took up a 40.6% share of Britain’s power mix over the quarter, followed by 33.1% from renewables, 17.6% from nuclear, 8.1% from imports and 0.5% from coal.
Wind was the biggest contributor of renewable generation, at 49.1% of the total renewable generation, followed by biomass (27.7%), solar (19.1%) and hydro (4.1%). Solar saw an increase of 18% in comparison to Q2 2018.
Paul Verrill, director of EnAppSys, said that “renewables continue to pave the way for a low-carbon future” as levels of clean generation rose above 50% for the third Q2 in a row, even with the fall in nuclear generation.
“Overall, solar, wind, biomass and hydro are combining to play an increasingly important role in Britain’s power mix,” he added.
Coal generation also saw a decline in Q2, hitting a record low 0.32TWh. This is down 60% on generation in Q2 2018. The electricity system ran without coal for a fortnight for the first time, its final total coming in at 18 consecutive days.
The EnAppSys report also pointed to 24 June, which saw system prices spike and Loss of Load Probability – the likelihood of the system being at risk of a blackout – climb to 17%. This was due to coal plants unable to fire up in time, as well as a coal plant tripping and leaving the system short of a reserve margin, Verrill said.
“The consequence was that the price at which parties are penalised for failing to deliver against their contracted position rose to £375/MWh, as coal plants were positioned in the market to be able to provide additional margin if needed. That evening, prices could easily have peaked as high as £1,000/MWh under a slight change in circumstances,” Verrill continued.