According to an analysis published by energy think-tank Ember, European solar output rose by up to 17 per cent during heatwave days in June and July, providing vital generation as electricity demand spiked by up to a quarter due to heavy air conditioning usage. The data highlights solar’s growing role in grid stability during extreme weather, even as rising temperatures strain other major power sources across the continent.
How European Heatwaves Drive Up Electricity Demand
Scorching summer temperatures across Europe trigger massive spikes in power consumption, largely driven by the sudden need for cooling. According to the International Energy Agency (IEA), space cooling—primarily air conditioning units and fans—consumed roughly seven per cent of global electricity in 2022. Even in regions with historically low air conditioning ownership, grids experience extreme stress during heatwaves.
Due to the widespread operation of air conditioning, France witnessed an evening electricity peak reaching 25 per cent higher than its typical off-season levels amid the early summer heatwaves. Ember’s analysis shows that daily electricity demand jumped significantly during the late-June heatwave. Compared to days prior to the heatwave, Italy saw a 28 per cent surge in demand, Hungary experienced a 23 per cent increase, France went up by 14 per cent, and Spain recorded a 13 per cent rise.
Solar Power Outperforms Other Major Sources During Peak Heat
Amid surging consumption, solar generation proved uniquely resilient. Ember found that solar was the only major power source to perform better than usual during the heatwaves. Compared with other days in June and July, average daily solar generation rose by 17 per cent in France and Hungary, five per cent in Spain, and remained flat in Italy.
“Solar is already doing heavy lifting during heatwaves, but the real challenge starts after sundown,” says senior energy analyst Chris Rosslowe. In the evening, when cooling demand remains high, the grid is most exposed to expensive gas-fired power.
Did You Know? Space cooling accounted for approximately seven per cent of the world’s total electricity consumption in 2022, according to International Energy Agency data, a figure that climbs sharply during multi-day continental heatwaves.
Droughts and Water Shortages Threaten Traditional Power Plants
While solar panels excel under clear, scorching skies, traditional power generation struggles severely during heatwave-induced droughts. Climate scientists note that Europe’s back-to-back heatwaves would have been virtually impossible without climate change, and the resulting weather extremes have severely depleted waterways.
Hungarian nuclear generation had to be scaled back because of dropping water levels on the Danube River, while specialists caution that Alpine hydropower production fell close to historic minimums. Coal-powered electricity also took a hit in Poland, where dwindling water levels in the Vistula River compelled authorities to curtail operations at a major facility.
These supply constraints drove electricity prices sharply upward. During the late-June and early-July heatwaves, average daily electricity prices surged 119 per cent higher in Hungary, 44 per cent in France, 13 per cent in Italy, and seven per cent in Spain compared to preceding weeks.
Why Battery Storage is the Next Frontier for Europe’s Grid
The stark price surges and evening generation gaps highlight an urgent need for grid-scale battery storage. Analysts emphasize that storage systems are essential for capturing excess daytime solar energy that would otherwise go to waste.
“While solar saves the day, battery storage can save the evening,” Rosslowe says. Together, storage and solar form one of the clearest ways to make Europe’s power system more resilient against increasingly severe summer heat. As solar output climbs and traditional sources falter, storage systems can carry cheap daytime electricity over into the peak evening hours.
Frequently Asked Questions
How much did solar output increase during Europe’s heatwaves?
According to Ember’s analysis, solar generation rose by up to 17 per cent on heatwave days in June and July compared to standard operating days.
Why do heatwaves cause electricity demand to spike?
High temperatures cause a sudden surge in the use of energy-intensive cooling systems, primarily air conditioning units and fans, driving up evening electricity peaks.
How do droughts affect nuclear and coal power in Europe?
Low water levels in major rivers like the Danube and Vistula limit the water available for cooling thermal and nuclear power plants, forcing operators to curtail generation.
What role does battery storage play during heatwaves?
Battery storage captures surplus solar energy generated during peak daylight hours and releases it after sundown, helping meet high evening cooling demand without relying on expensive gas-fired power.
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