A record heatwave in Western Europe during the final week of June triggered a sharp surge in electricity prices and added more than €700 million to consumer bills in France and Germany alone, according to a new analysis by climate group 350.org published Monday. The extreme heat is already taking a tangible toll on power systems and household budgets across the continent.

350.org's analysis, first shared with Euronews, compares the peak heat week (21–27 June) with a baseline week (14–20 June) and shows sizable extra costs. In that single week, electricity costs rose by roughly €371 million in Germany and about €360 million in France — a combined total of more than €700 million in additional spending.

Price shocks were particularly severe in the evenings, when solar output falls but cooling demand remains high. In Germany, wholesale power prices jumped from about €86/MWh at midday to €566/MWh by 20:00, the analysis shows.

Industry reports point to extreme local spikes: Montel News reported that on the evening of 23 June, prices in Belgium exceeded the EU average wholesale price by more than ten times.

Grid stress rose in step with the heat. Citing Eurelectric data reported by Yahoo Finance, daily electricity consumption in Germany increased from 1,267 GWh on 11 June to 1,396 GWh on 25 June, while France saw an even larger proportional rise. Energy News Pro recorded German prices reaching €545/MWh on 24 June.

The impacts extend beyond energy. On 28 June, the World Health Organization said Europe had recorded more than 1,300 excess deaths since 21 June. France's national public?health agency reported roughly 1,000 deaths linked to the heatwave.

Scientific assessments tie the anomaly to climate change: a World Weather Attribution study published during the heatwave concluded that an event of this magnitude would have been "practically impossible" without climate change driven by fossil?fuel burning.

The extra energy costs are being compounded by the wider external environment: elevated oil and gas prices are being fuelled by the ongoing crisis in the Strait of Hormuz. In this context, Andreas Zieber, head of political strategy at 350.org, urged governments to introduce a permanent windfall tax on fossil?fuel companies.

"Fossil?fuel companies continue to profit from crises they helped create," Zieber said. "Governments should permanently tax their excessive profits and direct the proceeds to protect citizens from heat, high bills and energy shocks."

350.org pointed to the precedent of the EU's temporary "solidarity contribution" introduced after Russia's 2022 invasion of Ukraine, which raised €28 billion that was largely used to help vulnerable households. The organization argues that similar mechanisms should be made permanent to help mitigate the economic and humanitarian impacts of future climate extremes.