Great Britain’s energy system operator has warned that “extreme temperatures” could hit power supplies on Thursday night, as the UK entered its third heatwave of the year. The National Energy System Operator (Neso) issued a notice overnight asking for extra supplies from power generators to cope with the added demand from households turning on fans and air conditioners.
The plea comes only weeks after Neso issued similar calls during last month’s heatwave, when the UK recorded a provisional high of 37.7C at Lingwood in Norfolk on Friday 27 June, smashing the previous June record of 35.6C set in 1976. While parts of southern England are likely to hit highs of 34C on Thursday, temperatures are expected to stay below June’s record-breaking levels, but the hot weather is due to last much longer, dragging out over 10 days.
“Neso warns of tight power margins as third heatwave drives demand, with no risk to customer supplies.”
“Our forecasts indicate tight electricity margins during tomorrow [Thursday] evening’s peak period,” Neso said in a statement. “This is due to extreme temperatures across Europe, reducing the availability of some generation.” The government-owned body added that its “electricity margin notice” was a routine tool used to balance the system and that “there is no risk to customer electricity supplies.”
Extreme heat puts pressure on the electricity system by making processes less efficient and because more people want to keep cool. While households are not expected to experience any supply interruptions, the notice raises the prospect of Neso again paying much higher than average prices to gas power plants to ensure demand is met.
Across the Channel, the French state-owned utility company EDF warned that the latest heatwave was putting a strain on its nuclear reactors, which regularly export power to the UK and Germany. Output could be curbed at up to five of its nuclear plants in the coming days, as hot weather affects the temperature of river water used to cool its reactors. It will start by reducing production and using only two reactors this week.