What Europe’s heat wave means for the power grid

Summer is getting hotter, and utilities need to adapt.

June 25, 2026

It’s been hard to look away from headlines about the European heat wave this week. Temperatures are breaking records across the continent, and the weather is threatening lives, shutting down schools, and in one particularly ironic case, forcing the cancellation of a London Climate Action Week event about extreme heat.

As the summer ramps up and we see this kind of weather sweep around the Northern Hemisphere, I’m always keeping my eye on the power grid. And one notable update that caught my attention this week was news that a nuclear power plant in the south of France had to close down because of the heat.

Climate change is squeezing the grid from all sides, affecting both supply and demand. Heat can affect power availability, from generation to transmission infrastructure, as I covered in my latest story. But climate change is also helping push electricity use higher—and countries in Europe and around the world will need to adapt.

In the US, nearly 90% of homes have air-conditioning. That means many grids see their highest demand in the summer months, and the risk of brownouts and blackouts is at its worst.

People are often quick to cast air-conditioning as a villain, and it’s true that the technology will account for a major chunk of the globe’s rising energy demand in the future. But the reality is that heat waves can be incredibly dangerous, and as climate change pushes temperatures higher, that risk is becoming more real in parts of the world that haven’t historically had to worry quite so much about heat.

In Europe, air-conditioning is historically much less common, with about 20% of homes across the continent using it. Some countries, including those getting hit by this heat wave, have even lower rates—the UK comes in at about 5%, and Germany is around 3%.

But those numbers are starting to tick up as people adapt to increasingly brutal summers. As they do, we should expect higher electricity demand, and stress for the grid—just as in the US. And utilities often have to look across borders to buy more power, driving prices up for everyone.

“The main pressure comes from a triple squeeze: Cooling demand rises sharply, while power plants and grids become less efficient, and some thermal and nuclear plants must cut output because cooling water is too warm or scarce,” says Simone Tagliapietra, senior fellow at Bruegel, an economic and policy think tank, via email.

Grid planning in the age of climate change generally means that we need a lot more supply, and quickly. But one interesting facet to this challenge is that in some places, seasonal patterns are shifting, compounding the difficulty of meeting demand.

Generally, grid operators plan maintenance and outages at power plants around expected  peaks in demand. Take nuclear power, for example. In the US, planned outages for maintenance and refueling tend to come in the spring and fall when demand falls below the summer and slightly smaller winter peaks.

Europe, however, has historically seen its grid peak in the winter, because electric heating is more common than air-conditioning. So some planned outages happen in the spring and into the summer, which is affecting the supply right now.

At the Golfech power plant near Toulouse in France, for example, unit two had to shut down this week because of the water temperatures in the nearby river, which is used to cool the reactor. But unit one was already offline because of planned maintenance and refueling, according to EDF, the plant’s operator.

We’re going to continue to see record-high temperatures around the world because of climate change. Communities are adapting, and utilities will have to follow. And if you thought this summer was hot, just wait until next year. With the El Niño weather pattern, 2027 could very well blow these heat waves out of the water.

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

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