What the heatwave reveals about Europe and what we can do about it
By Stijn Renneboog (Eurovent Deputy Secretary General)
Europe’s latest heatwave has hit a nerve in our collective consciousness. Last week, I received more interview requests than ever before, all asking about the same basic question: what role should air conditioning and other cooling solutions play as Europe faces rising temperatures and more frequent extreme heat events?
Everywhere I look, in the news and on social media, the same debate is playing out. What do these temperatures mean? What should we do about them? Are cooling systems necessary, wasteful, dangerous, inevitable, or overdue?
Cooling seems to have become a culture war issue.
I have reflected a lot on this in recent days, while preparing for interviews and speaking with colleagues and experts. I summarise those reflections here, in my own words and from my own perspective.
40°C: the new normal
The latest heatwave has again pushed Europe into temperatures that used to feel exceptional. Across large parts of the continent, national alerts were issued, infrastructure was disrupted, roads and railways struggled with the heat, and temperature records were broken.
Cities such as Paris, Milan, Prague and Vienna increasingly face summer temperatures approaching or exceeding 40°C. Buildings that were designed for a milder climate are now being used under very different conditions. For many homes, schools, offices, care facilities and hospitals, overheating is becoming a normal design condition.
Europe’s buildings were designed for the climate we used to have, not the summers we are now getting. These temperatures invite an obvious question: how are people supposed to keep cool, and what role should air conditioning and other technical cooling solutions play?
In many parts of the world, this question has already been answered. Air conditioning helped make modern urban life possible at scale in places such as Phoenix and Dubai. In the United States and Japan, more than 90% of households have air conditioning. In Europe, penetration is much lower, around 20% according to the IEA, and heavily concentrated in southern and Mediterranean countries.
This is not because Europeans are immune to heat. It is because, until recently, much of Europe could still treat cooling as optional. That assumption is now breaking down.
Europe’s problem with cooling is cultural, not technical
The big obstacle to mainstreaming air conditioning in Europe is not where to place the outdoor unit. It is the habit of mind of treating cooling as morally suspect.
There can indeed be practical barriers. Some have to do with the design of the building. Others have to do with regulatory restrictions, for example, linked to aesthetic or heritage considerations in cities and historic buildings. That said, these challenges are sometimes overstated. With qualified technical advice, a good solution can usually be found for many homes.
I think the bigger challenge is cultural. Old habits and practices die hard, and it takes time to adapt to new realities. Colleagues have told me, for example, that tenders for building development by the French state can still specify “no AC” as a principle, seemingly oblivious to the need to heat-proof buildings for 40°C-plus summers, which are becoming more and more common in that country.
But increasingly, I suspect that the debate is ideological. The mayor of Paris, for example, recently called individual air conditioning a “scourge” in an interview with Le Monde.
In tips circulating on social media on how to stay cool, I still see a lot of advice to avoid using air conditioning: “Stay hydrated, check in on each other, rub yoghurt on your windows…” But air conditioning? That is still treated in some quarters as a luxury or an extravagance.
Cooling is absolutely not a luxury
Heat is a serious public health risk. There are tens of thousands of heat-related deaths in Europe every year. The IEA has also estimated that access to air conditioning can and does avert such deaths.
In his controversial piece in Quillette, Maarten Boudry points out the contradiction: Europe has fewer hot days than many other parts of the world, yet it has very high heat mortality. One does not need to agree with every line of his argument to recognise the core problem. Europe remains poorly adapted to heat.
And this is not only about mortality. Heat affects the way people live, work, learn and recover. The Lancet Countdown estimates that heat exposure caused a record 512 billion potential work hours to be lost globally in 2023. Studies also show that high classroom temperatures reduce learning, while air conditioning can eliminate that effect. Heat also puts additional pressure on healthcare systems. The European Climate and Health Observatory reports that in Portugal, daily hospital admissions increased by 19% during heatwave days between 2000 and 2018.
To make the contrast even more stark, people do not have the same attitude towards space heating in winter. Heating is understood to be a necessity. In fact, the inability to heat one’s home in winter is termed energy poverty, a serious socio-economic and health risk, and governments take this seriously, including by providing support with energy bills.
Maybe it would be appropriate to have a similar recognition that the inability to keep one’s home safely cool in summer (which is the case for over 1/4th of Europeans according to this JRC report) is also becoming a serious social and public health issue.
Despite the pushback, demand for AC is rising
Reality is forcing the issue. Despite the challenges described above, demand for air conditioning has clearly risen over the past decade. Rising temperatures and more frequent extreme heat events are becoming impossible to ignore.
Eurovent Market Intelligence shows steady growth in the European AC market. This trend is also confirmed by modelling from the European Commission, which shows that the stock of room air conditioners in the EU increased from fewer than 7 million units in 1990 to around 57 million in 2020, and could exceed 100 million by 2030. Even though AC remains much less common in northern and north-western Europe, this is changing there too.
Cooling can be done sustainably, and we are well on our way to doing so in Europe
Some of the resistance to air conditioning has to do with concerns over sustainability and cost. I understand those concerns, but I think they are not well founded. Or at least, they are not arguments against cooling. They are arguments for doing cooling properly.
Cooling can be done in cost-effective and sustainable ways, by (1) using highly efficient cooling technologies, (2) with low climate impact from refrigerants, and (3) powered with clean electricity. Across those 3 dimensions, the trends in Europe are encouraging.
On efficiency, the industry continues to improve its cooling technologies. When the EU energy label was introduced for air conditioners, the scale ran from A to G. Today, it runs up to A+++, because new classes had to be added to keep up with improving efficiencies. According to an analysis of models registered in the EPREL database, 73% are now either A+++ or A++.
Of course, buyers do not always choose the best-performing solutions. Upfront cost often dominates. But better incentives, clearer information and qualified technical advice can help shift the market towards the higher-efficiency systems already available today.
On refrigerants, the industry is reducing leakage and moving away from high-GWP HFCs in line with the EU F-Gas Regulation. Recent VDKF data from Germany, for example, shows that average refrigerant leak rates fell to around 1% in 2025.
On electricity, the trend is also positive. Europe’s power mix is becoming cleaner. Eurelectric’s Power Barometer 2025 reports that clean electricity reached 72% of total EU generation in 2024, while fossil fuel generation fell to a historic low.
It is true that electricity demand is likely to increase, so grids and generation need to adapt. But the picture is more complex than simply “more AC means more electricity demand”. Many cooling systems are also heating technologies that can help reduce reliance on fossil fuel heating systems.
At the same time, Europe is seeing a seasonal shift: cooling degree days are increasing, while heating degree days are decreasing. In other words, yes, we will spend more energy on cooling, but we are likely to spend less on heating.
Moreover, demand for air conditioning often overlaps with peak solar generation. That makes cooling different from winter heating demand, and means efficient cooling can fit well into a cleaner, more flexible electricity system.
The idea that cooling is unaffordable does not survive contact with the numbers
On costs too, the concerns may be overstated. Yes, cooling a home during the hottest weeks of the year costs money. But in most European climates, this cost is still usually dwarfed by the cost of heating through winter.
The cost of cooling a home on a hot day may be in the order of €1 to €5, depending on the electricity price, system efficiency, weather, building condition and user behaviour. That is not nothing, especially for low-income households. But it is comparable to many other small expenses people accept in hot weather, such as buying ice cream, cold drinks, or going to a swimming pool.
And as mentioned earlier, many cooling systems are reversible heat pumps – they can also help reduce heating bills in winter. If governments taxed electricity as favourably as they did natural gas, the value proposition of reversible cooling technologies would look even better.
Air conditioning treats poor urban planning, doesn’t cause the disease
Some studies have shown that air conditioners can add urban heat, but I see that often these findings are not kept in proportion.
Yes, condensers reject heat outdoors. But most of that heat was already inside the building and is just being moved outside. Only the electricity used to run the system is additional heat added to the urban environment. That may be roughly 20-30% of the total heat rejected.
Moreover, air conditioning should not be portrayed as the main cause of urban overheating. Urban form, lack of vegetation, dark surfaces, heat-absorbing materials, poor airflow and bad building design are much, much bigger drivers.
In that sense, air conditioning is often treating the symptoms of poor urban planning, not causing the disease.
Cooling is not just split air conditioning
Another reason the debate is often confused is that people hear “cooling” and think only of split air conditioning units on façades. Those systems have an important role, especially in homes and apartments, but they are not the whole story.
There is a wider set of technical solutions. Air-to-air heat pumps can provide efficient cooling in summer and heating in winter. Reversible hydronic heat pumps can provide heating and cooling through water-based systems. Chillers and centralised systems can serve larger buildings very efficiently, and without needing many outdoor units. Smart ventilative cooling can use outdoor air, controls and night-time temperature differences to reduce overheating. Solar shading, better glazing, thermal insulation, reflective surfaces and building automation can all reduce cooling loads before active cooling is even needed.
The right answer depends on the building. There is no one-size-fits-all solution. But that is precisely why the debate should move away from slogans for or against air conditioning, and towards serious technical assessment of what each building needs.
Active cooling must become part of heat resilience strategies
There is just no way around this. Yes, Europe should absolutely reduce avoidable cooling demand through better buildings, shading, ventilation and urban design. But we are not going to solar-shade our way out of 40°C summers without continuing to incur the kinds of heat-related deaths we now see summer after summer.
The bottom line is simple. Make it easier to install efficient cooling in existing buildings. Support high-efficiency systems through incentives and standards. Integrate cooling into renovation policy, heat pump policy, grid planning and climate adaptation. Treat summer energy poverty seriously.
Europe does not need an air-conditioning free-for-all. It needs a serious cooling strategy.
Disclaimer: This article is an opinion piece intended to stimulate discussion. The views expressed are those of the author and do not necessarily represent the position of Eurovent, its members, or any Eurovent working group.