A severe European heatwave has placed unprecedented strain on the continent’s electricity system, driving electricity prices sharply higher as soaring temperatures increase demand for cooling while simultaneously reducing power generation. Millions of people across Europe have relied on air conditioners and electric fans to cope with record-breaking temperatures, causing electricity consumption to surge during peak hours. At the same time, extreme weather has disrupted several major sources of electricity generation, creating supply shortages that have pushed wholesale energy markets to multi-year highs.
Great Britain has been particularly affected by the combination of rising demand and declining domestic generation. To maintain a stable electricity supply, the country imported electricity from continental Europe at prices more than six times higher than normal during peak evening demand. The National Energy System Operator paid approximately £470 per megawatt-hour for imported electricity to ensure that sufficient power remained available between 5 p.m. and 7 p.m. These emergency purchases highlight how rapidly electricity prices can increase when weather conditions affect both electricity production and consumer demand simultaneously.
The heatwave has reduced output from several key energy sources across Europe. High-pressure weather systems have weakened wind speeds, significantly lowering electricity generation from wind farms in both the United Kingdom and mainland Europe. In France, unusually warm river water has limited the output of some nuclear power plants because reactors depend on cooler river water for safe and efficient cooling. Meanwhile, several British gas-fired power stations experienced unplanned outages as extreme ambient temperatures reduced operating efficiency, forcing five facilities to cut approximately 2.5 gigawatts of generating capacity—enough electricity to supply around 2.5 million homes.
Germany, Europe’s largest electricity market, experienced some of the most dramatic market movements, with wholesale power prices projected to exceed €545 per megawatt-hour, their highest level since mid-2024. France also recorded substantial increases, with electricity prices rising above €268 per megawatt-hour as temperatures approached 43°C. These developments demonstrate how weather extremes can rapidly influence electricity prices across interconnected European energy markets.
Renewable energy production has also faced challenges during the heatwave. Solar panels generally become less efficient as temperatures increase because excessive heat reduces their electrical performance. However, abundant sunshine across the United Kingdom largely offset these efficiency losses, allowing solar farms to continue producing approximately 14 gigawatts of electricity, representing about 35% of total national generation. Wind generation, however, declined much more significantly because the stagnant high-pressure system greatly reduced wind speeds. Wind supplied only 13% to 15% of the UK’s electricity during the heatwave, compared with an average of roughly 30% during a typical June.
To maintain system reliability, the UK energy operator secured an additional 1.5 gigawatts of electricity imports from neighboring countries while also encouraging households to reduce electricity consumption during peak periods through incentive programs. Consumers who voluntarily lowered their electricity use helped reduce demand by approximately 115 megawatts, easing pressure on the national grid.
The event illustrates the growing vulnerability of modern electricity systems to prolonged periods of extreme heat. Higher cooling demand, reduced renewable output, power plant limitations, and greater dependence on electricity imports all contributed to rising electricity prices. As climate change increases the frequency and intensity of heatwaves, energy systems across Europe may need greater grid flexibility, expanded storage capacity, more resilient power infrastructure, and diversified generation sources to better withstand future periods of extreme weather.