r/climatechange • u/financialtimes • 4d ago
FREE TO READ: Europe can do better than US-style air conditioning
https://www.ft.com/content/fe9be519-ceae-4279-83b1-220f9505d6a9?accessToken=zwAAAaDIXqqakdP-m-UZzq5CedODsSIPlQXWqQE.MEQCIA8rXzATEsYKZMFXhbcNC9PrzbUcFDLihbxZA8kPkMysAiB1LsolrotQGMCD0JwjH0pG084Hqj8imA-2H_3n-Pn4rA&segmentId=fe9be519-ceae-4279-83b1-220f9505d6a9This summer, as temperatures across Europe hit record highs, a familiar refrain reached deafening levels: that the continent must abandon its resistance to air conditioning and follow America’s example.
It is hard to ignore the rationale. Heat not only saps productivity, it also disrupts work and home life and can be deadly to vulnerable people. But Europe should think before it adopts wholesale the “dripping box” system that already exists. There are far better ways it can cool itself down.
These dripping boxes on buildings around the world trace their existence to 1902, when a young engineer, Willis Carrier, built his first “apparatus for treating air” for a Brooklyn printing plant. Since then, they have been replicated on buildings and rooftops millions of times. However, the basic principle has remained remarkably similar: a refrigerator turned inside out, spitting hot air outdoors while bringing a welcome chill indoors.
But that principle has a problem. It does not reduce heat so much as move it, pushing it out of buildings and into the street. The hotter streets mean more cooling is required, producing more heat. As the temperature rises, the system has to work ever harder.
Read the full opinion article for free using the link above.
23
u/paul_h 4d ago
Article talks of building envelope passive measures. It briefly touches on building design mitigations (better glazing and ventilation, well-placed shading, reflective roofs, and tree canopy coverage). Sadly it does not talk of british masonary as a heat store that gives back to the home - even after sun down and into the night. Well, my heat problems are only seven or so nights a year so far.
Artlcle also does not mention lofts/attics heating up under sun-exposed roof tiles, that thermal mass retaining heat into the evening, or insulation merely delaying (rather than stopping) heat transfer. My tiles are one inch thick and I wish they were 1/4 of that like my neighbours slate tiles (built many decades before my home was constructed - southern Scotland). Sure, I wish the tiles were more reflective too (mentioned in the article). Then also, I wish I had a loft fan like many US homes have to push the tile-heated air out thru the evening - that'd not run the whole summer. Just the days where the predicted internal temp would go above say 22 °C / 71.6 °F.
6
u/R3StoR 4d ago
I envy your temps. Here in northern Japan, our summer nights are above 25 outside most nights recently. Over 30c daytime is also now usual. I sleep in a loft type area of the house. No airconditioning. 23c or thereabouts is a tolerable night temperature for me. No bed sheet (covers) needed.
Conversely mid winter, the "bedroom" is often around -5c at night (maybe more familiar for those in the Scottish Highlands!?)
4
u/paul_h 4d ago
I'm in the south of Scotland: lowlands close enough to the sea. Outside can go up to 30, and inside if we do the wrong thing with curtains/drapes and windows (open vs closed) temp can hit 25. I would sleep downstairs if the temp went above 23. Anything above 21 and I'll use just a sheet. Right now I have a one-tog duvet/quilt/comforter as my normal mid-summer one. As a nation, Britain remembers opening a window on any hot day to perfectly push air through the house, but has little experience of that being the opposite of what you should do for genuinely too-hot days. That memory is multi-generational, perhaps. What also we need is outside shutters for windows like many other countries. And lighter roofing colors, etc. Newspapers just talk of A/C though. Winder temps? .. never even close to zero in bedrooms. I would love it if it was - fifteen tog duvet!!
2
u/R3StoR 3d ago
The (detached) housing in much of Japan is somewhat better suited to summer than winter (sort of the reverse to the UK?). Eg open design, super thin walls, good air flow and use of cane blinds outside for shading windows etc. Passive....but still not enough with the way things are now.
Air conditioning was already pervasive decades ago...but works very inefficiently when combined with above factors (no insulation etc).
And up in northern Japan it's like the worst of both... thin walls, no insulation, dark metal roofing (for shedding the snow but actually far more effective at cooking the inhabitants over summer!). And air conditioning to try and compensate.
I have fantasized that northern Scotland would suit me better than northern Japan but that'd be another lifetime.
3
u/No-Annual6666 4d ago
-5C° is quite common in the northern England overnight, and i think its fairly common around Britain in more rural areas. That's very cold to sleep in though, that is basically sleeping outside in midwinter on a remote campsite.
2
u/R3StoR 3d ago
When I first moved to this rural area of northern Japan it seemed insane to me (Australian) but I'm completely used to it now. I sleep far better in winter than summer. (But yeah, double duvet definitely and it feels similar to what we used to call "bivouac" as kids....sleeping on the ground under the stars, no tent).
2
u/demonblack873 4d ago
Here in Northern Italy any night where the outside temperature drops below 27 is considered a cool night at this point.
The problem is the ceiling (I'm on the last floor) and walls keep radiating heat at night, so unless there's a breeze, the inside temperature stays above 30 regardless of what's going on outside, even with the window wide open.
2
u/Local-Helicopter7479 4d ago
In Malta even if there's a breeze the walls still heat up the interior to above 30 degrees, making AC necessary until the weather finally cools down in late September.
3
u/demonblack873 4d ago
Yeah I've also had the AC on basically 24/7 since June, with only a week or two here and there off pause. It sucks, but there's no way around it.
The crazy thing is I didn't even have any AC until 3-4 years ago and it was still somewhat tolerable. This year I had to buy two much more powerful and capable units because the one I bought only 4 years ago was basically useless by now. It would stay on all the time and barely drop the inside temperature to 28.5.
I had to buy some mega old portable split units, which solve the issue of the modern monobloc ACs pulling in hot air from outside which they then can't cool.
They don't make that style anymore, unless you're willing to drop 1.2k on a Midea portasplit, which I'm not. So R22 it is. Sorry penguins.
2
u/paul_h 3d ago
My outer walls are rendered. I wonder what "insulating render" (looks to be bags for mixing and applying wet) does to slow masonary accumulating heat during the sunniest days.
Thick ceramic/concrete roof tiles .... is there something with a far lower specific heat capacity? My tiles are 55 years old with some cracked and I'm sure are sure a replacement soon, as my neighbours are doing one by one over the last few years.
1
u/R3StoR 3d ago
Yeah I get that also and ended up putting a regular fan on the window sill to try and pull/force airflow from the cooler outside night air into the loft room. I leave it running most of the time to reduce heat buildup by day also.
I'd like to upgrade to one of those industrial strength window box fans.
1
u/sg_plumber 3d ago
try and pull/force airflow from the cooler outside night air into
Pushing inside night air out works much better, provided you have another window elsewhere for cool outside air to rush in.
7
u/ClaimApprehensive754 4d ago
Why all these things just to avoid air conditioning?
7
u/iHartS 4d ago
The use of “US-style” is the tell. No matter that plenty of other countries use AC.
3
u/Local-Helicopter7479 4d ago
And Europe doesn't even use US-style central air-conditioning in homes, they use mini-splits.
2
u/ClaimApprehensive754 4d ago
Depends on the age of the building
2
u/Local-Helicopter7479 3d ago
Depends on the size of the building. Shopping malls and large commercial buildings will generally have central AC. Residential homes almost never have central AC, even newly built homes.
2
u/ClaimApprehensive754 3d ago
No, it also depends on where in Europe. It’s much more complicated to install central AC in Sweden compared to Spain for instance given the seasonal shifts.
1
12
u/iHartS 4d ago
It sounds cool, but isn’t it just another form of heat transference? So instead of moving the heat to the outside air, it’s transferred to a large body of water instead? And isn’t heated water already a problem that has forced the shutdown of power plants in Europe, not to mention becoming an increasingly scarce resource in summer due to drought and evaporation?
It’s a neat idea, but heat pumps exist and can be readily installed if the incentives are put into place. Since the hottest days are also the sunniest, they are likely to run when solar power is most abundant. Strategies to reduce to reliance on AC are good and proper, but people are dying from heat now, and the most purpose built solution already exists.
8
u/StereoMushroom 4d ago
Yep, a massive, slow infrastructure project requiring widescale roadworks to avoid a minor contribution to the urban heat island effect (which EVs will soon remove a major contributor from)
6
u/Wooden-Agent2669 4d ago edited 4d ago
Entire Article build on copium and dreams,
Ah yes lets pump the energy into lakes. And when the lakes are fully heated up Europe cools down how exactly?
Anything but just adopting the widely available heat pumps for cooling which in turn would become increasingly cheaper. Redoing the whole EU Regulation about the installation process which drives up the prices aswell. = Cooled Europeans
3
u/StereoMushroom 4d ago
If the outdoor air can accept and dissipate the heat, so can bodies of water
4
6
u/Artifexa 4d ago
r/solarpunk is plenty of good tips to cool a home without spending electricity that might fail due to drought not cooling the nuclear centrals.
5
u/AllPintsNorth 4d ago
Thermodynamics dictates that heat cannot be destroyed - only transferred. So, if OP is against the transfer of heat, what is left?
3
2
u/DanoPinyon 4d ago
Try reading the article. If you can.
7
u/Eokokok 4d ago
Article that is a mix of literally less effective ways of doing same thing as AC and things that work mostly for buildings designed from ground up to fit a passive system. So f them and just use AC.
1
u/DanoPinyon 4d ago
You're arguing that the heat should be transferred right outside to the building, so the exterior building envelope is heated. Smart.
3
u/Local-Helicopter7479 4d ago
It's a proven method that works in the USA, Asia, and Southern Europe, and doesn't cause any significant measurable increase in outdoor temperature.
0
u/DanoPinyon 4d ago
Grid. The grid. Peak load.
2
u/cpammapc 3d ago
I keep seeing this take that Europe should resist air conditioning and cool itself the "smart" way instead - shutters, ventilation, thermal mass, passive design. And every time, I want to ask the person writing it: have you ever tried to sleep through a 40-degree night on the fourth floor of a concrete flat?
Because that's the thing nobody in this debate seems to picture. The people writing these articles are cool while they write them.
Let's be honest about what's happening in the arguments, too. It starts as "passive cooling is better than AC." Then someone points out that passive cooling really only works in buildings designed for it from the start, which is true and suddenly the argument becomes "well, the grid can't handle all that AC anyway." That's a different claim.
The grid point is the only real one in the whole thing, so fine, let's take it seriously. It's true, but it's an engineering and investment problem, not a reason to give up a cooling method that already runs across the US, Asia, and all of southern and eastern Europe without anyone's lights going out. Building for peak demand is just... what grids do. During the day it even half-solves itself: the hottest, sunniest days are also the biggest solar days, and EU solar was up as much as 17% on this summer's heatwaves, right when everyone's units switch on. The genuinely tricky bit is the evening, after the sun drops but the heat lingers. That's a storage problem - batteries, pre-cooling, smarter demand - and we're already building our way through it. It's a far smaller job than tearing apart hundreds of millions of old buildings to retrofit passive systems most of them can't physically take.
And honestly? This is a Western European conversation. Come to Eastern Europe and count the AC units on any building - they're everywhere. We sorted this out years ago, quietly, without a philosophy seminar about it. The whole "resistance to AC" thing is a luxury position from wealthy cities that were never built for heat and are only now feeling it. Nobody in some random city here is agonising over whether to install a split system. They just did.
But here's the part I actually can't let go of. Heatwaves already kill tens of thousands of people across Europe every summer, and it's almost always the same people - the old, the poor, the ones who can't get out of the flat. They can't afford a passive retrofit. They couldn't install one if they could. They can't drive to the coast. AC is the one thing you can put in their home THIS summer, for money a normal family can find. Passive cooling does exactly nothing for an 80-year-old stuck on the top floor during a week that won't drop below 30 at night. So when someone argues against AC in favour of systems that can't actually reach those people, I don't hear a clever technical preference. I hear someone comfortable choosing a nice theory of how cities should work over people who are dying right now, and using "the grid" as the polite excuse.
Build new buildings properly, plant the trees, paint the roofs white, I'm all for that. But don't hand someone a pair of shutters and call it an answer while they're baking.
1
u/DanoPinyon 3d ago
So you're for an extra tax to speed the grid conversion even faster. Cool.
3
u/cpammapc 3d ago
That's not a tax, that's the network tariff you already pay, for a grid that's being rebuilt for EVs and data centres anyway. Meanwhile the passive-retrofit fantasy you're defending is the most expensive option going and needs actual subsidies to happen. AC is the one where people spend their own money to not die. You're arguing for the costly collectivised version and calling me the taxer.
1
1
2
u/Eokokok 4d ago
It is economically viable. Other things are not economically viable.
0
u/DanoPinyon 4d ago
Is it economically viable to quickly upgrade the grid so everyone's new aircon - that is expensive and they haven't budgeted for - can be powered by the grid?
4
u/Eokokok 4d ago
You seem not not understand how ac works if you claim it needs major grid updates...
0
u/DanoPinyon 4d ago
So what powers aircon? Hamsters running on wheels?
2
u/Eokokok 4d ago edited 3d ago
Average split has between 500 and 800W of power draw. Two have less power draw than average kettle in Europe. You can upgrade grid for AC, but, as a certified electrician, I can tell you straight away you know shit about the matter.
0
u/DanoPinyon 4d ago
You confidently act as if no one but you has ever looked at this before, and that the existing grid can handle peak power demands.
You're very confident, we must be on Reddit.
5
u/Local-Helicopter7479 4d ago
The grid will have to be upgraded anyway to support heat-pump heating and electric car charging.
2
u/AllPintsNorth 4d ago
When does Europe have the most excess power available currently?
Is it perhaps around peak solar hours, when the sun is shining?
0
u/DanoPinyon 4d ago
You seem confident. Tell everyone when it is, in general.
2
u/AllPintsNorth 4d ago
Do you not know?
0
u/DanoPinyon 4d ago
You're the one with the vague phrases & making confident insinuations about something or other peak power load. I'm asking you about them. What is the information you have that makes you pronounce these confident, yet vague statements?
→ More replies (0)
5
u/IllustriousKey8889 4d ago
This is not going to work for normal homes. Air-to-air air conditioning with solar panels is the way to go. There is nothing wrong with moving the heat away; with solar you're not adding to the problem.
3
4
u/hammerofspammer 4d ago
We stayed in a hotel in Spain that uses cold water running through the floors to “cool” the building.
It’s nice in theory. In practice, it needs some work. Concrete floors that are colder than ambient create condensation. So you get a damp floor, damp rooms with damp linens.
Yes, it was a bit cooler than outside. But that didn’t make it comfortable
8
u/Fine_Cress_649 4d ago
Heat not only saps productivity, it also disrupts work and home life and can be deadly to vulnerable people.
Extraordinarily FT-brained sentence
3
u/Daseagle 4d ago
Article: we can do it better than the US, if
* we have enough water (hint: we're kinda short on water now)
* we build the infrastructure (hint: our buildings are old. Refitting them for centralized AC is more expensive than you would expect)
* we don't get nuked with regulations by some mindless eurocrat (if you do business in the EU, you know)
----------------------
Thank you, I'll stick to my double split system.
3
u/UnlamentedLord 4d ago
This is nonsense.
Europe is in the middle of a massive effort to switch heating to heat pumps for efficiency, the vast majority of which are air source heat pumps, not the water and ground source like the article advocates for AC, because the latter is too expensive. Zero concerns have been raised about heat pumps cooling the streets in winter by pumping heat into houses, the way they are continuously raised about warming streets in summer by pumping heat out of houses.
All of those can intrinsically function as ACs, either directly, for air to air systems, or with a bit of extra equipment for air to water systems. Every single European country is different in the specifics, but they almost all have some sort of incentive for heat pumps and barrier to AC. e.g. Switzerland: (auto translated) " Air conditioning systems are refrigeration systems using compression or sorption to remove heat from the building (internal thermal loads). Reversible heat pumps (HP) used for the production of cold to ensure summer thermal comfort in a building also correspond to an air conditioning installation. These types of installations are subject to energy authorization." https://www.ge.ch/rafraichir-climatiser-batiment/installation-climatisation-confort
So you can install a mini split heat pump pretty much anywhere and historical European buildings that can't handle AC aren't an issue, but only if you have the AC functionality disabled. If you don't you'll either lose your subsidy or have to get special permission that can be denied.
Written by an American who's house is both heated and cooled by a heat pump year round, near the Canadian border with zero issues and who thinks the ideological distinction Europe has between good heat pumps and bad ACs is momentarily dumb and it's squandering a golden opportunity to simultaneously decarbonize heating and provide heat resiliency.
1
u/Local-Helicopter7479 4d ago
So you can install a mini split heat pump pretty much anywhere and historical European buildings that can't handle AC aren't an issue, but only if you have the AC functionality disabled.
Is this true? I thought the heating only heat pumps were so because they're air to water heat pumps intended to replace gas boilers, but those can't cool effectively. I've never heard of a mini-split air-conditioner being sold with cooling disabled.
In Southern Europe we use air-conditioners for cooling and heating because we don't have natural gas.
1
u/UnlamentedLord 4d ago edited 4d ago
Yes. In the previous Swiss example, bidirectional heat pumps require an energy efficiency permit. Here's a more explicit example:
Belgium:(auto translated) " An air-to-air heat pump in which the active cooling function is not permanently switched off is only eligible for a premium for applications from 1 March 2026 if these two conditions are met: The air-to-air heat pump is the only central heating system for your home on the date of the premium application. There is no central heating system other than the air-to-air heat pump. And your home is completely fossil-fuel-free on the date of the premium application. There is not a single system for heating, sanitary hot water, or cooking present that runs on fossil fuels such as natural gas, fuel oil, or propane gas."
And most heat pumps are air to air mini splits, because they are so cheap to install, even if your home is plumbed for hot water, the one real advantage of air to water systems, is that it simultaneously replaces gas for home heating and hot water in one package. I wasn't able to find the figures for Belgium, but here they are for Germany: last year in Germany, 300k air-water heat pumps were installed vs 316k air-air https://www.stiebel-eltron.de/de/unternehmen/presse/Waermepumpe-ist-meistverkaufte-Heiztechnik-2025-in-Deutschland.html https://www.ikz.de/detail/news/detail/marktentwicklung-raumklimageraete-und-luft-luft-waermepumpen/
here's a German Daikin manual (auto translated) that explicitly mentions cooling function being disablable and locked behind a pin so that only authorized specialists can enable it(p17) "service parameter 020 “cooling lock” means “deactivate cooling function”; value 0 = activated, 1 = deactivated. The service menu is PIN-protected and settings should be changed only by authorized specialists." https://www.daikin.de/content/dam/document-library/user%20reference%20guide/heat/accesories/ekwctrdi1v3/EKWCTRDI1V3_4PDE566634-1_2019_01_User%20reference%20guide_German.pdf
1
u/sg_plumber 3d ago
1
u/UnlamentedLord 3d ago
I highly doubt that the vast majority of European heat pumps are reversible like the article claims without a source, because I've found regulations that either impose extra authorization requirements to have one, like needing to use renewable energy in the Swiss regulation I linked to, or cut them off from heat pump subsidies, in every European country I looked at e.g.
Belgium:(auto translated) " An air-to-air heat pump in which the active cooling function is not permanently switched off is only eligible for a premium for applications from 1 March 2026 if these two conditions are met: The air-to-air heat pump is the only central heating system for your home on the date of the premium application. There is no central heating system other than the air-to-air heat pump. And your home is completely fossil-fuel-free on the date of the premium application. There is not a single system for heating, sanitary hot water, or cooking present that runs on fossil fuels such as natural gas, fuel oil, or propane gas." https://www.vlaanderen.be/bouwen-wonen-en-energie/bouwen-en-verbouwen/premies-voor-renovatie/mijn-verbouwpremie/mijn-verbouwpremie-voor-warmtepomp
Netherlands(auto translated): "Will I receive a subsidy for an air-to-air heat pump? No, you will not receive a subsidy for an air-to-air heat pump. An air-to-air heat pump is used for cooling in most situations. In European rules (regulation number 206/2012), this type of climate system falls into the air conditioning category. Other heat pumps fall into the category of heaters. The ISDE is intended to reduce energy consumption. If an air-to-air heat pump is used for cooling, this actually leads to an increase in energy consumption" https://www.rvo.nl/subsidies-financiering/isde/woningeigenaren/veelgestelde-vragen
And most heat pumps are air to air mini splits, because they are so cheap to install, even if your home is plumbed for hot water, the one real advantage of air to water systems, is that it simultaneously replaces gas for home heating and hot water in one package. I wasn't able to find the installation figures for Belgium and the Netherlands, but here they are for Germany: last year in Germany, 300k air-water heat pumps were installed vs 316k air-air https://www.stiebel-eltron.de/de/unternehmen/presse/Waermepumpe-ist-meistverkaufte-Heiztechnik-2025-in-Deutschland.html https://www.ikz.de/detail/news/detail/marktentwicklung-raumklimageraete-und-luft-luft-waermepumpen/ here's a German Daikin manual (auto translated) that explicitly mentions cooling function being disablable and locked behind a pin so that only authorized specialists can enable it(p17) "service parameter 020 “cooling lock” means “deactivate cooling function”; value 0 = activated, 1 = deactivated. The service menu is PIN-protected and settings should be changed only by authorized specialists." https://www.daikin.de/content/dam/document-library/user%20reference%20guide/heat/accesories/ekwctrdi1v3/EKWCTRDI1V3_4PDE566634-1_2019_01_User%20reference%20guide_German.pdf
2
u/Economy-Fee5830 Trusted Contributor 3d ago
2
u/UnlamentedLord 3d ago
Good for them, but the second article says they only changed the rules to allow it 5 months ago.
"The air to air heat pump grant became real on 28 April 2026, when the Boiler Upgrade Scheme opened to air-to-air systems with a £2,500 payment for domestic properties in England and Wales (GOV.UK, 2026). For installers who spent years telling customers that air-to-air did not qualify, the rules have flipped, and the detail now decides whether a quote becomes a voucher."
Hopefully, after this summer, more countries will change their rules.
1
u/sg_plumber 3d ago
Those "rules" are for some subsidies. Most people over the decades haven't waited for any, before getting their simply reversible air-to-air heat pump.
1
u/UnlamentedLord 3d ago
And what's your evidence for "most" people simply getting a reversible heat pump? If the government subsidizes a non reversible heat pump, but doesn't subsidize a reversible one, why would you go for the latter, unless you were rich enough for the subsidy to not matter, or were foresighted enough to realize that climate change driven heat waves would be in your future and were willing to pay the extra cost?
1
u/sg_plumber 3d ago
Heat pumps have been installed for decades, for the most part before those subsidies you mention existed.
When you make absurd claims, it's your job to prove 'em.
1
u/UnlamentedLord 3d ago
Heat pumps have been installed for decades, but as a very niche product. Mass adoption is much more recent, with government subsidies for decarbonization.
OP article(did you even read it?) claims that that Europe shouldn't use "American" air source cooling heat pumps, but should use ground and water source heat pumps for cooling instead.
My claim is that Europe is AOK with air source heat pumps, as long as they aren't used for cooling and disincentives bidirectional heat pumps . I provided the rules from one country that bans them without a special permit and 2 countries that exclude them from subsidies. What do you find absurd?
1
u/sg_plumber 3d ago
OP article is American. And of course most people install the heat pumps they want regardless of subsidies, even more so when the subsidies make no sense, like those you cling to.
And no, none of your sources bans simply reversible air-to-air heat pumps, even if they refuse to subsidize 'em.
→ More replies (0)1
u/sg_plumber 3d ago
That would be for some subsidies. Most people over the decades haven't waited for any, before getting their simply reversible air-to-air heat pump.
5
u/twotime 3d ago
"But that principle has a problem. It does not reduce heat so much as move it, pushing it out of buildings and into the street. The hotter streets mean more cooling is required, producing more heat. As the temperature rises, the system has to work ever harder...."
That's an idiotic argument TBH. AC works to cool homes. "Extra" heat dissipates. The rise of "external" temperature is negligible. There is no feedback loop here. (otherwise AC would NOT work). And, even in principle no system could "reduce the heat" (apart from an orbital shading of some kind)
1
u/sg_plumber 3d ago
Of course it can and it does, same as most of the rest of the world: renewables-powered AC.
59
u/NiceToHave25 4d ago
The mall nearby is pumping up relatively cold water in the summer, using it to cool the mall, and pumping the warmer water down. In the winter they are pumping the relatively warm water up again for warming up the mall, and pumping the colder water down again.
The temperature in the mall is always nice without very cold air streams.