Europe’s ongoing heat wave is piling pressure on its electricity system. Surging demand for air conditioning, with temperatures staying high into the evening when solar output falls, combined with the high-pressure system behind the heat wave stilling the air and limiting wind generation, have forced power networks to scramble.

Britain’s national grid issued, then retracted, a call for more power as the buffer between supply and expected demand grew tight; electricity prices hit $740 per megawatt Wednesday evening, up from $100 in the morning. In France, several nuclear plants went offline as they were unable to cool sufficiently. Germany and the UK are on track to see their highest June average electricity prices since the 2022 energy crisis, Bloomberg reported.