GREAT BRITAIN — The National Energy System Operator issued a notice requesting additional electricity supplies from power generators to meet increased demand on Thursday night. This action occurred as the UK experienced its third heatwave of the year.

The National Energy System Operator stated it was giving participants the opportunity to make any additional generation or flexibility available during the forecast period. The operator said: "Our forecasts indicate tight electricity margins during tomorrow [Thursday] evening's peak period."

The operator attributed the tight margins to external factors, stating: "This is due to extreme temperatures across Europe, reducing the availability of some generation." Despite this, the National Energy System Operator stated: "There is no risk to customer electricity supplies." It described its electricity margin notice as a routine tool used to balance the electricity system.

The operator added: "We will continue to monitor conditions closely and take any actions necessary to maintain secure electricity supplies."

The UK recorded a provisional high temperature of 37.7C at Lingwood in Norfolk on Friday, June 27. The previous June record temperature was 35.6C, set in 1976. Parts of southern England were expected to reach highs of 34C on Thursday, with the hot weather predicted to last over 10 days.

EDF warned that the latest heatwave was putting a strain on its nuclear reactors. The power supplier said output could be curbed at up to five of its nuclear plants in the coming days. Hot weather affects the temperature of river water used to cool EDF's nuclear reactors.