But while both sides of the Atlantic face the heat, the reality for families and businesses could not be further apart.

The difference, once again, is air conditioning.

Find yourself in the U.S. this week and you’ll likely move seamlessly between air-conditioned offices, malls, and homes, barely registering the heat outside.

In Europe, that same week means hunting for a desk fan or racing to one of the few public spaces with real cooling.

Around 90% of U.S. homes have air conditioning; in parts of Europe, that figure is closer to 20%. While America was built to cope with high temperatures, vast areas of Europe remain woefully unprepared.

To a certain extent, this makes sense. America has traditionally experienced higher temperatures and its homes and buildings were deliberately built to withstand them. Much of Europe, on the other hand, was built for a different climate entirely.

The heat has been rising in Europe for years. This latest heatwave is not an isolated event — each summer brings higher temperatures and greater risks for infrastructure and public health.

A year ago, I wrote about the economic cost of Europe’s cooling gap. That liability has hardened into an unavoidable threat. The heat is on, and adaptation is critical.

Figures suggest Europe could be at risk of losing up to 7% of its collective GDP in the next four years due to heat-related losses. That’s separate from the even greater cost to human life. More than a thousand deaths have already been recorded from this heatwave alone.

So why are we still so far behind the U.S. when it comes to protecting against extreme heat?

Demand for cooling infrastructure has surged in recent months. In the U.K., widespread AC installation was a key recommendation in plans for adapting to extreme heat. And in France, Marine Le Pen is gaining ground with some of the opposition to her plans for subsidized AC across the country.

It’s the right ambition — yet a significant hurdle remains: the grid.

A Grid Suffering From Heatstroke

Europe’s aging grid infrastructure was not designed to cope with the heat.

This week demonstrated the impact. Tens of thousands of homes were left without power in France as the grid buckled under the heat. In the U.K., the national grid operator made its first-ever summertime plea for more power, as forecasts predicted an imbalance between supply and demand. Meanwhile, sagging electrical lines threatened to bring some rail services to a standstill.

America’s grid faces similar physical stress from heat — overheating cables, sagging lines — but Europe faces an additional layer: a critical lack of capacity to absorb new demand from cooling infrastructure.

This “thermal squeeze” — outsized demand colliding with an overheating grid — is Europe’s defining vulnerability. While the U.S. has widespread AC already connected to its networks, Europe is attempting to build it on top of an already overwhelmed grid. Plugging in hundreds of thousands of electricity-intensive AC units could push ailing networks over the edge.

The solution lies in faster, smarter infrastructure planning — investment is underway, but the pace must accelerate.

Modeling a Cooler Europe

Addressing this challenge starts with more advanced, intelligent modeling of the infrastructure to pinpoint exactly where grids are most vulnerable, how installation would impact supply, and where targeted adaptations could unlock the capacity needed for new connections.

This gives planners a clearer picture of existing infrastructure and enables smarter decisions that minimize cost and disruption.

The same technology can safely simulate future weather conditions, allowing us to see how energy networks will react and take preventative action. Understanding which power lines are likely to fail at which temperatures allows targeted repairs or supply adjustments to keep local homes and businesses connected. This kind of future-proofing matters on both sides of the Atlantic.

Better modeling could also accelerate solar connections — solar flourishes in the heat and could sustainably power energy-hungry AC systems. Right now, Europe’s grid cannot safely absorb a solar surge, as the Iberian blackout demonstrated with devastating clarity. Any sudden spike in supply or demand risks cascading failures.

The U.S. faces a parallel problem: grid bottlenecks and permitting delays threaten to stall solar’s potential. On both sides of the Atlantic, the renewable energy exists to power cooling adaptations — but grids need their own significant upgrades to handle it.

As extreme weather intensifies, Europe needs data-led planning to build the cooling capacity that America’s example proves is achievable — without letting the infrastructure collapse in the process.

Europe can’t simply copy the American blueprint, but it has no choice but to act. Fail to adapt, and as temperatures climb, Europe will sweat the consequences while its neighbors across the Atlantic keep their cool.

The opinions expressed in Fortune.com commentary pieces are solely the views of their authors and do not necessarily reflect the opinions and beliefs of Fortune.