The biggest heat pumps in the world
60 comments
·December 16, 2025willvarfar
jack_tripper
Sign of a rich and very developed country.
A lot of buildings in Austrian cities are still heated by burning oil or wood and the whole city smells like a bonfire.
Probably gonna have my lifespan shortened by at least a decade from all that fossil fuel pollution, but at least we banned that dirty nuclear from killing us.
wkat4242
Yes heat pumps are expensive and you need different radiators and more insulation than with traditional gas central heating. That's why it's an issue in Holland too. Not many people have the investment for all that. It's mainly worth it when you have solar panels but that requires another big investment.
I'm lucky to live in Spain where it's not that cold so I just have one little plug in radiator I use a few months a year lol.
hexbin010
Ditto UK.
Gas is relatively cheap, and a replacement boiler is £1,500 to £3,000 and will last ~10 years and there'll be no doubt about whether it can sufficiently heat the home or produce enough hot water etc .
Lucky you living in Spain though lol
stephen_g
Longer term this shouldn’t be the case though - a fridge is just a heat pump, and an air-to-air or air-to-water heat pumps aren’t that much more complicated, nor should they be any less reliable.
It’s something that will become more of a commodity and eventually won’t be any more sign of wealth than owning a fridge.
I mean, we can see it already in air-to-air systems - I’ve had mini-splits supplied and installed here in Australia for something like 10% of the cost I’ve heard quoted for equally sized units in the US, for example - just because basically every electrician has a license to install them here because they are so incredibly common (for cooling even more than heating, but they can basically all so both here). Air-to-water I expect will be the same in cold climates - in 15 years basically any plumber will be able to do it and they’ll be far cheaper than today.
jack_tripper
>Longer term this shouldn’t be the case though
Long term I'll be dead anyway. To me the the actions taken in the present is most important that what maybe might happen 30 years from now since that's why everything is fucked in Europe, because everyone coasts on hopium for the long term instead of fixing the present.
Ekaros
Air-to-Air heat pumps can be quite affordable. Or even cheap if you find no name deals. There is install, but even that is not really that significant. This is at least in Nordics.
jack_tripper
Probably not for entire apartment buildings since most of them run on oil or gas burning here. I only saw heat pumps on apartment buildings built after 2020 or the single family homes in the affluent areas.
moooo99
As a German, I find the popularity of heat pumps in the nordics especially amusing. In Germany heat pumps were an incredibly political topic and people were pushed by some media outlets to really hate heat pumps. One recurring topic was that heat pumps can‘t work at German temperatures.
lnsru
Nothing amusing. Germany is not really rich compared to nordics. And now let‘s do so math! Electricity: 0,3€/kWh and gas 0,1€/kWh. I need ~3x more gas to get same temperature in my room. And gas heating costs €10k while heat pump €40k without subsidies and probably raw €15k material cost if I install it by myself. So why should I pay more by €30k to install experimental thing for a decade when my low cost gas heating will last for 3 decades again. The monthly bill is the same.
stefanfisk
What is the calculus behind 40k? I just checked some Swedish vendors and here they calculate 12k for hardware and installation of a fairly large heat pump.
https://www.polarpumpen.se/kunskapsbanken/varmepump-kunskaps...
pjc50
The problem is the gas (a) emits CO2 and (b) comes from Russia.
looofooo0
Well Norway (Hydro), Sweden (hydro and nuclear) and Finland (Nuclear Wind Hydro) all have cheap electricity which seems to be the main driver for adoption.
mrmlz
Hrm. It might be cheaper than in Germany but its not cheap in Sweden except for the most nordic parts (hydro).
South Sweden - i think the prices are more on par with germany.
hexbin010
From the PDF at your link:
"Heat pumps are more efficient than gas boilers and become competitive when the electricity price is lower than around three times the gas or oil price"
Sweden seems to have quite high domestic gas rates (highest in EU I think?), around £0.18/kWh, with electricity at £0.23/kWh so I can definitely understand the adoption of heat pumps with gas being so high.
In the UK we have lower heat pump adoption, which could largely be explained by gas being ~£0.06/kWh (and electricity is ~£0.27/kWh). There is also the barrier that many houses are draughty and would require significant expensive upgrades
DrScientist
Electricity prices are certainly a factor, and retro-fitting can be very expensive to nigh on impossible.
The real scandal in the UK is how the updates to building regulations to bring in higher energy efficiency have been delayed and delayed - presumably due to lobbying by UK house-builders.
Given the big push to build large numbers of new houses it seems madness not to have the higher standards in place.
jcsager
Planning rules conflict with building regs in the UK. Planning means that most new houses are little boxes made of little more than ticky-tacky. So adding insulation to the walls makes them even smaller inside.
calaphos
> heat-pump equipment costs roughly €500,000 per megawatt of installed capacity
Interestingly enough the price for these giant heatpumps is pretty much in line with domestic ~10kw units.
BoppreH
> The Mannheim heat pump setup will cost €200m ($2.3m; £176m).
Browsing on mobile, I saw no way of contacting them about the mistake.
PunchyHamster
At that rate the article will be eventually correct, give it few years
esskay
Looks like its already been corrected
unwind
Heh came here to post the same comment, I was somewhat shocked by the alleged power of the almighty dollar ... but it's just a typo of course. Phew. :)
According to Google's built-in exchange rate calculator it should say $235m.
looofooo0
Germany at its best, instead of keeping its 20GW+ nuclear power running and get district heating pipes installed to them, they engineer this solution at x times the cost. In this case a 30km pipe from Philippsburg NPP would have done the trick.
Maledictus
Guess who supplies all the nuclear fuel? Russia, and we don't want to buy from them anymore. The same is true for pretty much all nuclear power plants.
looofooo0
No, this is a lie. It is also funny because Germany was so depended on Russian Gas that nuclear fuel even if fully depend on would be laughable.
Germany has its own fuel enrichment and production, and it is still running https://de.wikipedia.org/wiki/Urananreicherungsanlage_Gronau
And no Uranium ore does not stem from Russia, they might still produce some of the UF6, but this can be much more easily shifted because unclear fuel cost are only a small fraction of the total cost!
octocop
Dumb question, why is the water in the Rhine warm?
Someone
It not warm as in ”warmer than the typical living space”, but it is warmer than zero Kelvin, so heat can be extracted from it.
Doing that takes energy, that’s why it is called a heat pump. That moves heat from the water to an already warmer place, against a heat gradient, just as a water pump moves water against a gravity gradient.
If the water were warmer than your typical living space, they wouldn’t need a heat pump; a water pump to pump the water closer to where heat is needed would be sufficient.
kijin
Practically, the water would need to be somewhat warmer than 0℃ because you don't want it to freeze and clog the plumbing after you have extracted a useful amount of thermal energy. :)
consp
Depending on the contaminants, it's more likely a few degrees below 0C but you point still stands. Fish are removed as contaminant but minerals and pollution likely is not.
And normal water takes quite a bit of heat extraction to actually freeze if at 0C, maybe the device does not even extract enough. But you want to be on the safe side of course since clogging up your heat exchanger with ice (which expands) is not great.
(edit: and as noted in other reply pressure is a thing)
ahofmann
Moving water will get much colder than 0℃ before turning solid. -10℃ or even -25℃ are easily possible. If the water is also under pressure, it can get even colder.
greazy
The river is not warm or warmer than the air. Heat pumps are amazing at extracting thermal energy. I think water is very dense compared to air, thus making the processes more efficient in such a large scale.
alextingle
The best thing about using watercourses as your heat source for heat-pumps - the water flow naturally takes away your "colder" output and brings you more "warmer".
Ground source heat pumps are limited because the ground they have chilled stays stubbornly in the same place, so the only way you can extract more heat from it is to make it even colder, which gets less efficient. Watercourses don;t have that problem.
georgefrowny
The opposite effect is also why thermal stations (including but not only nuclear) are usually on the coast or near large rivers: you can dump a lot of water heat into water and have it carried away.
Not always good for the local ecosystem without mitigation, but at least one Japanese reactor allowed local colonisation by tropical fish and local legend said the same about Sizewell.
Sizewell C claims to plan recover waste heat and use it for carbon capture somehow, about which all I can say is a big old hmmmmm.
crote
It has a decent bunch of thermal mass, so it takes quite a long time for it to reach air temperature during a cold snap or heat wave. This makes it a decent heat source during the winter and cold source during the summer - especially for short-term peaks.
You could get an even better result using the earth itself, but that is way harder to scale.
PunchyHamster
It isn't. It's just warmer than air in winter
alextingle
The air temperature isn't relevant.
pbmonster
It is, since the obvious alternative to taking the heat from water would be taking the heat from the air or from the ground.
The air is colder in winter than the water, and the ground only provides a limited amount of heat before you can't extract any more. So water beats both.
georgefrowny
It is a bit relevant because if the air was warm enough you would be better building huge air source heat pumps.
And if it was really warm enough you wouldn't need heating in the first place.
null
ErroneousBosh
> ... modelling suggests the system will affect the average temperature of the river by less than 0.1C.
Okay, so that clears up the question I had, then. Not enough to make any appreciable difference.
There used to be a coal-fired power station on the east coast of Scotland, a little south of Edinburgh, Cockenzie, where the cooling loops dumped a huge plume of warm water into the sea. It was well-known as a local fishing spot, with surprisingly clean water flow detectable even a mile or so out from shore. That was several degrees warmer and definitely had a (possibly positive) influence on the ecology of the area - there were certainly a lot of interesting things swimming around there.
cyberax
So $235 million for 162MW, or $2.35B for 1.6GW
A 1.6GWe nuclear reactor is around $8B.
masklinn
These are… completely unrelated ratings?
The heat pump generates 162MWt, at the cost of around 50MWe.
The nuclear reactor produces 1.6GWe alongside 4.5GWt.
Furthermore the listed costs are also unrelated: the 235 millions are for the bare units (and an estimate for something a few years out), while the 8bn are turnkey (of what exactly I’m not sure: the beleaguered Olkiluoto 3 and flamanville 3 cost 11~12bn, while Taishan is estimated at under 8 for two reactors).
pjc50
.. those are somewhat unrelated things, though?
willvarfar
A heatpump needs power to operate, but will generate at least 3x more heat than the electricity to power it.
The article describes how there will be a water battery.
So it can be thought of as a part of a bigger countrywide or europe-wide plan and grid?
pjc50
Sure, but if you build a nuclear reactor suitably close to your city (!) it produces hot water directly in addition to electricity. It's just a much bigger pain to ship hot water over long distances than electricity.
In the nordics we love heat-pumps! Something like 70% of houses are heated by heat-pumps, and 90% of apartment buildings are heated by district heating and that is often generated by huge heatpumps.
Apparently 95% of new heating installations in Swedish houses are heat-pumps these days: https://publications.jrc.ec.europa.eu/repository/handle/JRC1...
Heatpumps have been heating nordic homes for decades. Even in the countryside where many houses have small woodland attached, people I know have moved to heatpumps for convenience and because its affordable.
PS: shoutout to to the JRC, found their reports when doing a super quick dig for stats. Those reports were super easy to read :D