How data centers cope with heat waves

Europe is sweltering. The summer of 2026 has seen historic heat waves that have taken a significant toll on infrastructure. In recent weeks, across the continent, problems have been reported in the power grid, telecommunications, and rail transportation. IT infrastructure has not been spared from the situation.

“The heat affects equipment long before anyone notices a problem,” explains Ricardo Román, sales director at Fracttal, in an email. “Every piece of equipment has a temperature range within which it is designed to operate, and when it operates above that range, it begins to degrade silently,” he says. A process of wear and tear begins that will eventually take its toll. With technology, this happens much faster. “In a data center, this effect is amplified because there’s no margin for error,” he notes. When something starts to fail, everything grinds to a halt.

In fact, this latest heat wave has already had negative impacts on data centers outside of Spain. In the United Kingdom, high temperatures shut down hospital data centers and caused the University of Cambridge’s Dawn supercomputer to go offline, as its cooling systems were unable to cope with the temperatures. That’s the crux of the problem. “In IT, heat isn’t a computing problem—it’s a problem of maintaining the assets that support the data center,” explains Román.

Heat thus becomes yet another risk for the IT industry and, in particular, for data centers.

Temperatures are a clear and growing concern when it comes to corporate risk prevention. “I see it in conversations with clients: In the past, the maintenance team was the one monitoring the temperature in a technical room,” Román says. “Today, management also monitors it, because they know that if that goes down, the service goes down—and behind the service is the end customer,” he adds. Maintenance has gone from being a cost “to a lever for business continuity that no one dares to touch.”

As a World Economic Forum analysis warns, we’re experiencing a boom in AI-driven data centers, but the impact of climate risks on them is being overlooked. Their estimates suggest these risks could result in an additional annual cost of $81 billion by 2035 and $168 billion by 2065. These calculations include all kinds of threats, such as floods or droughts, but most of the impact comes from extreme heat.

These projections are confirmed by data from the industry itself: Over the past three years, extreme weather events have accounted for one-third of the losses incurred by the U.S. division of the data center company Zurich. According to projections by the climate risk analysis firm First Street, 79% of global data centers will face increased risks from extreme weather. MapleCroft estimated in 2025 that 56% of major data centers had a high or very high risk rating for extreme heat, and that this figure would rise to 80% by 2080.

These percentages cannot be easily extrapolated to Europe in general—and to Spain in particular—as one might think, although they do make the trend clear. Guillermo Benito, CTO of Nabiax, points out during a video call that these studies are based on global samples and thus place significant weight on the capacity of Asia and the United States. “We represent a small percentage there, but that said, all countries will have to adapt. The two major challenges for data centers are energy and cooling,” Benitonotes.

Spain: A pioneer in heat?

In late June, French Labor Minister Jean-Pierre Farandou proposed taking a training course in Spain to learn how to prevent high temperatures from paralyzing a country. Although Spain’s climate varies by region, high summer temperatures are common in many areas (though climate change has made them more extreme and frequent in recent years), and the infrastructure of knowledge and solutions that Farandou wanted to learn about has been established. The big question is whether this also applies to data centers. Is Spain better prepared than other European regions?

“Heat waves are becoming increasingly intense and frequent. What used to happen once every two years now happens two, three, or four times a year,” Benito says. Speaking from his own experience, he adds: “In Spain, data centers already take these factors into account.” When it comes to redundancy, monitoring, or maintenance, these factors are already factored in. “It’s not like it’s an unforeseen event. It’s already been taken into account, and we build in a lot of redundancy—a wide safety margin,” he says.

The difference compared to central or northern Europe is that some haven’t considered this possibility. Benito points out that the same thing happens with homes. “For many years, they’ve been designing with two assumptions: that they have plenty of water because their climates are humid, and that it never gets hot,” he says. And this is a problem, because their summer temperatures have risen significantly during extreme heat waves. “Temperatures in the UK have gone up by 10 or 15 degrees, and their data centers aren’t prepared for that,” he says. In fact, he shares an anecdote about “a certain hyperscaler that, a few years ago, when its data centers in the United Kingdom went down, held a global conference to figure out how this had happened and draw lessons from it.” The curious thing is that what they learned was something that was already well known in Spain.

İsmail Enes Ayhan | Unsplash

It was already getting hot in southern Europe, and preparations were needed. Now, temperatures are becoming a topic of conversation outside the region, and climate change has made its way into IT strategy. Benito confirms that, yes, the conversation is more visible in global settings. “For several reasons. The first is because, obviously, it affects operations. Another is the market. Customers also demand that you address this.” Before, the focus was on power capacity and square meters. Now, the expert points out, people are asking where the electricity comes from and whether it’s clean, and they’re demanding emissions guarantees. The sector is making significant investments to become sustainable, he argues.

Beyond consumption data and the improvements that can be made, the big question is whether these high temperatures are already impacting decision-making—whether decisions on where to locate data centers (or not) are already being made with heat in mind.

Industry representatives explain that while the climate can have an impact and is already taken into account when deciding where to locate a data center, it is not yet the sole factor or the most decisive one. In other words, many other factors must be considered, and these carry much more weight in the decision-making process. One such factor is energy, which is essential for these infrastructures and must be constant, resilient, and have a low carbon footprint. It is also an area where cooling plays a major role. As Román points out, cooling can account for between 30 and 40% of energy consumption, “and in poorly managed facilities, that figure approaches 50%.” Energy efficiency and cooling efficiency are thus essential—and not just for sustainability reasons. “It’s a matter of the bottom line.”

Another factor is space. As Benito says, you need “stable locations where you can grow.” This isn’t just about whether the infrastructure fits, but also about how it aligns with the needs of its customers. As this expert points out, the concentration of data centers near Madrid or Barcelona isn’t “just a whim,” but because you need to be close to large population centers to provide them with low latency. “Other supercomputing applications can be located farther away, and that’s already happening,” he explains, but generally speaking, you can’t just put data centers anywhere. You have to strike a balance between needs and available space.

How to survive the heat

So, how can we survive the heat, especially when projections suggest that the future will bring even higher temperatures? The key is to understand that this is no longer a curiosity or an occasional incident. As Román points out, air-conditioning systems are running longer and longer. What worked 10 years ago will now barely suffice—it’s “pushed to its limits.” “Heat is shifting from being an August blip to a variable that must be monitored year-round. One you endure; the other you manage.”

“By the time the room’s thermometer rises, it’s already too late. What you need to monitor isn’t the room—it’s the equipment—and you have to do it sooner,” he says. Román recommends a three-step strategy. First, don’t measure the environment; instead, measure the equipment and its variations in temperature, vibrations, and energy consumption. Next, take action on any deviations: Don’t wait for a failure, but instead act on early indicators that things aren’t normal. And finally, keep a comprehensive record of historical data, which will be key to anticipating issues and learning from them. “And here I’m going to be honest, because this is what I see every day: The technology to do all this already exists and isn’t expensive,” he asserts. “Many critical facilities are still managed using an Excel spreadsheet and the memory of a technician who’s been there for twenty years,” he warns. And that’s a problem.

In the specific case of data centers, Spain has done its homework. The high temperatures (which exceeded those recorded in the United Kingdom, where some data centers did shut down) did not bring them to a halt during this heat wave.

Unlike what might happen in other countries, Spain has optimized its cooling systems to be efficient and sustainable, as Benito explains, noting that the country must also contend with water stress. “In other countries, I can use water and let it evaporate as I please because I know it’s going to rain again—or at least that was the case until recently. In Spain, we’ve known for a long time that this isn’t the case,” he says. That’s why we work with closed-loop systems. “Most of us operators don’t use any water,” he says. The same water, mixed with certain cooling agents, circulates continuously. “Once the loop is filled, we don’t lose a single drop,” he asserts.

What this expert is now seeing at international conferences is that in other countries where water wasn’t an apparent problem, people are starting to talk about working this way—”as a technical innovation.” “That’s where we say, ‘Yes, just like the ones we have in Spain or Portugal,’” he remarks with a touch of humor. “Water, like energy, is a challenge,” he says, so everything has already been designed with that in mind. It isn’t wasted, it doesn’t evaporate, and it isn’t consumed, he says.