Extreme heat drove electricity demand higher across Europe this summer, while drought and low river levels constrained nuclear, hydropower and thermal generation.
Temperatures exceeded 40 degrees Celsius (104 Fahrenheit) in many parts of Europe in June and July, leading to a surge in air conditioning use, according to international energy think tank Ember.
During heat waves in late June and July, daily electricity demand increased by as much as 28% in Italy, 23% in Hungary, 14% in France and 13% in Spain, compared to the week preceding heatwaves on June 13-19.
Low water levels and high water temperatures reduced electricity generation in several countries.
Two reactors at Romania's Cernavoda Nuclear Power Plant were taken offline, while generation at Hungary's Paks Nuclear Power Plant was gradually reduced, with several units temporarily shut down due to insufficient cooling water, due to record-low water levels in the Danube River.
In France, 29 gigawatts of nuclear capacity was unavailable on July 12, although most of the loss was related to planned maintenance and other factors. Ember estimated that up to 11 gigawatts was affected by forced outages or environmental constraints.
- Tighter supplies lift electricity prices
Drought also reduced coal and gas-fired generation in Britain, Italy and Poland and took a toll on hydropower generation across Europe. EU hydropower output in May, June and July fell to its lowest level in at least a decade.
In the UK, declining output from five gas-fired power plants took 2.5 gigawatts of capacity offline, while low water levels in Italy's Po River affected around a third of the country’s thermal power plants.
In Poland, falling water levels forced around 1.3 gigawatts of coal-fired generation capacity offline.
Tighter power supplies also pushed electricity prices higher.
During heat waves in late June and early July, average daily prices rose 119% in Hungary, 44% in France, 13% in Italy and 7% in Spain compared with comparable days in the previous week.
On Aug. 11, the European Commission said that the system remained stable and faced no short-term supply risks, although conditions were expected to remain tight.
- 'Solar helped prevent worse price increases'
Chris Rosslowe, senior energy analyst at Ember, told Anadolu that all forms of electricity generation could be disrupted when extreme heat is accompanied by drought.
Plants that require water for cooling were particularly vulnerable, Rosslowe said.
Solar was the exception, Rosslowe said. "Solar is the only major power source that performs better than usual during heatwaves, which often bring clear and sunny conditions."
EU solar generation reached records of 52 terawatt-hours in June and 55 terawatt-hours in July, supplying 25% of the bloc's electricity in both months.
Solar power helped offset some of the strain as it provided stability to Europe's grids and "prevented worse price increases, especially during daylight hours," Rosslowe stated.
He said that price spikes typically occurred in the early evening hours and combined with supply tightness, exposed a lack of flexibility and storage in Europe's power system.
"They have been intensified by high gas prices, which remain about double their level before the US-Israel war with Iran," he said.
- 'This summer should be turning point for storage'
Rosslowe said Europe's power system needs to be designed for the possibility of frequent heat waves and other climate-related extremes.
"The power system needs to be planned not for the weather today, but for a hotter future with increasingly common heatwaves," he said. "Assumptions about thermal power plant availability need to be updated."
With solar set to play a growing role in Europe's electricity mix, Rosslowe said additional storage capacity could allow more of its output to be used after daylight hours.
"Additional storage could shift this growing low-cost solar power into the evening, better aligning supply with cooling demand and reducing reliance on expensive and vulnerable thermal generation," he said.
"This summer should be a turning point for energy storage," he said. "Not only can storage add resilience for heatwaves, but it can help to decarbonise the energy system more deeply."
By Firdevs Yuksel and Handan Kazanci
Anadolu Agency
energy@aa.com.tr
