The biggest heat pumps
bbc.com
bbc.com
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
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.
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.
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
Norway is really a different kind of rich compared to the rest of europe, they have tons of oil rights all over the world (and as such they still contribute a lot to global warming even though they have a lot of money for 'green' tech at home).
PS yeah Spain is good for heating but not for AC though (which I don't have, sadly). But I do enjoy life here a lot more even though I would make much more money in Holland.
Are the boilers typically connected to water-radiators?.. I assume so based on the word "boiler".
There are heatpumps that are used to heat water so it would be a slot in replacement..
You don't see them on new builds, I think, probably because the pipe going from inside to outside would reduce insulation effectiveness.
Otherwise people try to retrofit narrow drain pipes in the walls which are prone to clogging or give you poor flushing performance. Or outside big enough pipes outside interior walls where you get to hear every flush/shower unless you build a box around that. Easier to just run it outside if you can configure your bathrooms that way.
The pump is a drop in replacement unless you have 8mm "microbore" piping, at which point the lower temperature times restricted flow rate becomes a problem in terms of getting enough heat through.
And a dirty tank of water in the attic to act as a "in-house water tower" because only one tap may be connected directly to the mains. Really archaic.
Would you say modern (i.e. <10 years) are properly insulated and built or are there still... shortcuts?
and that house still has the sewage stacks on the outside of the house, as do almost all homes in Bath and environs.
I had a quote for a heat pump - £20k, plus the cost to replace 13 radiators, plus cost to replace pipework to support heat pump rads.
Pretty sure the government ‘incentive’ was £3k at the time. Doesn’t come remotely close!
Modern condensing combis I think are designed to be more complex and not last as long. I'm not sure all the complexity and fancy modulation etc is really worth it myself. I'd rather have a boiler that lasts 20 years and that any half-competent gas engineer can fix with a spanner and some spare parts.
£20k, jesus!
Far from ideal solution, but it is mostly green, somewhat offset by the solar panels, and actually more comfortable than the old system because of the more even heating. Set to 20C and forget about it for the season. I'm hoping that it will last until the actual gas phaseout when a solution compatible with 8mm piping will exist.
This is why they need to be mandated on new houses, because it's so much better than trying to retrofit it.
It was £2500 to replace the oil tank, or I could opt for £2250 to install a heat pump with the government grant. This included all plumbing, electrical work, installation, and 6 new radiators all over my house.
Honestly to me it seemed like a no-brainer. It’s a tad more expensive to run, but it works really quite well and is a lot less invasive than a big smelly tank of kerosene. I gained another 90cm of width in my garden, it’s actually quieter than the oil boiler, and it doesn’t stink in the summer- win win.
Otherwise the heatpump just can't catch up.
And currently I have the opposite problem. The house is too well insulated for the heater (or the heater is too powerful). The heater only runs for a couple of minutes and huts off.
There have been a few cold snaps here where the weather has been down to -2 some days, but it’s been fine. I had a couple of minor installation issues (eg 3 way valve set incorrectly) but once those were fixed my house hasn’t dropped below 19C.
Nothing to do with a heat source.
In that regard, an air-to-water heat pump is much lower temperature than a gas or oil boiler can efficiently produce.
That can cause a need for larger radiators to compensate and sometimes for insulation if the radiators can’t be further increased in size. (Or if the heat loss at design temp is too high for available or sensible sized equipment.)
This means that people now really need to improve insulation of their homes big time, before even being able to consider switching to a heat pump.
My house has a 30kW gas heater. When I switched to a heat pump, first I had to replace the entire roof with PIR insulation. It was previously just uninsulated wood. Now I can easily heat my home with a 7kW heat pump (which most of the time doesn't even need to produce 7kW of heat).
I was lucky, my house already had insulated walls and floors, and used floor heating (low temperature heating). Most homes here use high temperature radiators, which become way less efficient when used with low temperatures produced by heat pumps.
So for many people here, it is cost prohibitive to switch to a heat pump, as they first need to improve isolation and replace their radiators for a heat pump to even work.
Switching to a heat pump can be anywhere from 10-25k depending on the existing plumbing, size of heat pump etc.
Why is this ? (Sorry if it's a stupid question.)
You might need other radiators if your current radiators are very small. But you also might not in a recent house, or in a recently renovated house (e.g. the radiator are still sized on single-glazing-glass when having double glazing installed).
You can also choose in-foor heating with the next renovation, a lot of homes already have in-floor heating and it's very comfortable. You can probably also boost existing radiators with small fans on the bottom or choose an electronic back-up module which boost the temperature a bit on the coldest days.
Tldr: it really isn't that hard. The focus on hybrid systems in NL is purely thanks to a lobby from gas-boiler installers and manufacturers. Air/water heatpumps are a drop-in replacement in a lot of cases.
But then neighbours start complaining about the look of the outdoor units and causing hassle with court orders etc. Really if they want people to move they should make it easy and cheap, so invalidate cosmetic complaints automatically.
The install itself isn't that hard they come pre-charged with refrigerant. I have installed a few of the air-to air myself and had no issues. All you need is a vacuum pump and proper refrigerant manifold or adapters. Vacuum out the lines for at least an hour to draw out all the air and moisture, close valve and let sit for an hour, if the gauge shows no leak, open the heat pump zone valves and you're in business.
A friend did it and had all the refrigerant leak out after a year but he realized the flared end that came from factory was malformed so he cut and re-flared the end, vacuumed out the system, left it overnight, saw no leak, and had an AC tech do the charge. Was solid after that. A from zero charge requires some knowledge of the systems capacity and a scale to weigh the charge so he hired someone to do it.
Example: https://www.highseer.com/products/pioneer-kwik-e-vac
I think I spent $200 in parts on Amazon and have done 4 heat pumps now. It's a vacuum pump, a scale, and a digital manifold/guage. Punch the numbers for subcool/superheat into a calculator and use the temp probes on the lines where they connect to the condenser and you can even skip the scale.
In the US, you can get your EPA 508 cert online in a couple hours and buy the refrigerant online. (You need the cert to be legal, but it’s not really checked just to buy.) Tightly regulated is not true in practice. You could buy some in 3 minutes online and have it Monday.
In France, access to the gas technically requires a certification that is not available to regular people. You need to be professional and bow to the bureaucracy.
I know somebody who was required to pay the full installation price for a heat pump he installed himself because there was no professional that was willing to charge and launch the installation for the small fee it should require.
This is the hypocrisy and value-destroying behavior of EU collectivist governments. They tout ecological solutions, but you need to pay far more than is reasonable for those modern solutions. Predictably, people chose things that are worse but cheaper, like wood-burning stoves or pellet stoves.
Those things are made artificially expensive for no good reason, and that's because they get built overseas mostly, and this happened because of regulations in the first place. Then they wonder why the EU is losing ground economically…
From what I understand, self-install should be fine up to a 12m run, but if you let too much gas leak, you may have issues because of low pressure.
At least now you can buy them for relatively cheap. Mine required a swap of the control board on the inside unit, and it was ridiculously expensive (almost as much as buying a new unit). I am not sure why it fried, but probably bad solder from old age (it's about 15 years old at this point).
It's an excellent technology, but the surrounding business feels extremely shady.
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 20% 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.
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.
A heat pump would make a lot more sense if electricity were cheap; alas, we went all in for renewables while ignoring nuclear for political reasons. The result is expensive electricity while still having a dependency on fossil fuel and even importing the renewable tech. That makes no sense in the short run, and I very much doubt it will make any sense eventually.
these are slightly odd, however: they either need an external air intake set up, or they require that the water (tank/heater) be located in a space that you don't mind being cooled down (often quite significantly) AND that isn't thermally connected to the space you're heating via other means.
still great technology, but deployment can be a little more challenging that space heating/cooling.
IIRC Dave Jones of EEVBlog fame has shown a air-to-water heat exchanger that he has at his home. It's outside. And the climate in Sydney is generally warm(ish), so it makes perfect sense there.
I can also see them being useful in parts of the American South where big garages being common and the weather gets hot: Take some of the heat from the garage and convert it into hot water for showering and cleaning. Win-win.
But they're not so hot, per se, in my part of Ohio, where unfinished basements are commonly used as utility spaces.
My own basement, for instance: As unfinished basements go, it's pretty good. It's not a bad place to hang out and work on stuff any time of year. But it's a big space, and it's cold down there in the winter because I don't want to pay to warm it up. Despite being cold, that's really the most-suitable place for a conventional water heater for this house -- and it's where the house was designed to have it, too.
But if I were to "upgrade" to a heat-exchanger water heater, then as a practical matter I'd be making my already-cold basement even colder.
If it ever got cold-enough down there to make supplemental heat desirable (or worse: necessary), then it'd be an absolute loss: Burn energy over here in one place in the basement to try to keep it warm, and use that energy down the way a bit to concentrate into a tank full of hot water, while the basement stays cold.
Even if it I had a nice modern mini-split down there to provide that supplemental heat: That would mean having air-to-water heat exchanger that is backed up by an air-to-air heat exchanger that is already at the edge of its efficiency curve because it's cold outside. The combination would be reprehensibly dumb: A complicated Rube Goldberg system that costs more to buy, more to maintain, and more to run than approximately anything else would. (I might even be better off just burning my dollars directly.)
(The smarter move for my own home, in Ohio, would probably be a gas-fired tankless water heater, since they leak almost no heat while not being used.)
Uhhh, better to put the unit inside the home where it provides a bit of a/c. Double win if you cool the compressor with incoming water.
Not in the south myself, but with trad water heaters, I find it dumb that I’m heating incoming 5-10C municipal water in summer time when I could have a tempering tank/loop letting the interior air warm it up (and getting a tad of “free” AC) to 20-25C first before paying to apply heat to it. Would improve “capacity” of the heater too.
Even in winter time, my home heating is more efficient than most water heaters (even if they’re both gas, water heaters are typically non-condensing, and actively pump out warmed interior air for combustion), so it makes sense all year round.
But not everybody has those opportunities. Not every home has an existing conditioned space within which to put a water heater. Not every person is equipped (mentally or physically) to engineer and use tempering loops and/or water-cooling compressor motors.
As a practical matter: In a warm-climate home that already has a water heater in the garage (which is very common in the American south, from my limited direct observation), replacing a traditional water heater with one that uses a heat pump can make a lot of sense.
This replacement is something that any person and a friend with minimal plumbing and electrical experience can accomplish on their own in one afternoon, without incurring the expense and inconvenience of relocating their water heater somewhere else. There will be no drywall dust, and no paint.
It's a natural fit.
---
And don't take any of this the wrong way. You've got some great ideas there.
But not all environments are the same. During the warmer months in my own city, I've measured incoming water at 76F/24C -- warmer than the house, and also warmer than the basement where the plumbing lives. A tempering loop may make sense for you in your environment, but it would be the opposite of useful in my environment: "Oh neat! A thing that makes my home harder to cool in the summer!" (Unusual? Perhaps. But it's my reality anyway. I've never run out of hot water in this city during the summer. Not even close. But things do change in the winter -- maybe I'll measure the input temperature again when I get home tonight.)
It's fun to think about niche concepts that don't have broad-scale adoption. And sometimes, it makes sense to set forth and make them a reality.
But it's always important to remember that there's often very real reasons for them to remain niche concepts that aren't broadly utilized.
Same house, same tap, same thermometer as the previous summer reading. It went from ~room temperature to ~60F/16C in a hurry. That's about the temperature of the basement right now.
It then dropped to about 48F/9C as water from the pipe under the street was introduced, and it stayed at that temperature. That'd be great for an incidental cooling loop, except: It's rather cold outside and it will remain cold for months. :)
Probably helps that we are in a pretty moderate climate here. And thanks to global warming it's been a while since it got really far below zero degrees celsius.
When the outside unit really can't keep up with demand, it may switch to a gas heater (hybrid) or an electrical heating element (all-electric)
edit// Hot water is generated by electric solar panels. 1200w are sufficent to have enough hot water for two persons
You need to find another reason. Looking at IMF 2025 GDP per capita figures (https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi... ):
Norway: $92k
Denmark: $77k
Sweden: $62k
Germany: $60k
UK: $57k
Finland: $56k
So yeah, Denmark and particularly Norway are a bit richer than the others, but the others are in the same ballpark.
If I had to bring up some particular reason, gas grids are more or less non-existent in the Nordics, and electricity is cheaper than in central Europe or UK.
"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
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.
While electricity is priced off gas, current heat pumps do not have a strong economic case.
The prices plummet from time to time, even going negative, but not enough for the prices to be lowered.
Seemingly it’ll take a few more years for more energy to reach the south, but by then data centres may be using more.
South Sweden - i think the prices are more on par with germany.
That is why so many houses here now have air-to-air heat pumps. That is by far the cheapest way to improve heating in an old house with only electric radiators and no existing water heat pipes.
https://www.polarpumpen.se/kunskapsbanken/varmepump-kunskaps...
But especially with old houses, with any "not insignificant change" to your electrical setup, you have to bring everything up to modern standards.
Also, and connected with that, metering is weird in Germany. If your consumption rises above a certain amount (I think 10MWh for a single-family home) you are required to get a "smart meter", meaning a digital meter which includes the possibility (just the possibility, not actually the real thing) of online reporting and minute-by-minute pricing. In the rest of the world, that would just be swapping the meter or slapping some Wifi-to-IR-interface on it, but not so in Germany. You need to install a new metering cabinet that provides space for at least one digital meter (but better provide more than one...), one remote control receiver (for old-style night/day tariff switches, obsoleted by smart meters but still required nonetheless) and a smart meter gateway. That new metering cabinet needs to conform to standards set by your local electricity supplier (which can be as small as a city), so there is no nation-wide standards, more like 50 of them. And the metering cabinet is huge, not someting like the 30x40cm thing you see on sidewalks in spain or something, no. More like 200x140cm in the smallest(!) version. So those are really expensive just because the market is tiny and the requirements are completely crazy: Even though most smart meter gateways are wireless nowadays (UMTS or GSM) and usually such a gateway won't be installed anyways (because just the possibility of installing one is required), you also need to provide for cabled internet uplink to the metering cabinet. That uplink is a Cat6 cable to the gateway, but it crosses through the electrical uplink part of the cabinet. So the insulation of that cable has to be certified for at least 10kV insulation voltage, at least 80A current on the shielding and more stuff like that. So e.g. just that one stupid half-meter Cat6 cable will set you back 50Eur. Installation isn't any less crazy. You definitely cannot do anything yourself. Even your licensed electrician can only do the menial preparations. When your licensed electrician is done with the prep, you request an appointment with the local supplier's meter installer, who, after a typical wait time of 2 months, will install and seal the meter in the presence of your licensed electrician (who is there to receive complaints about incorrect prep, followed by another 2 months wait time for another appointment...).
That's why it's 4kEur...
And if you want your power to be a few cents cheaper (28ct/kWh instead of the usual 35ct/kWh), you need an extra meter for your heat pump. Have solar? Another extra meter. Want to charge your electrical car? You guessed right. And you cannot bring your own. Each of those "smart" meters has to be rented from your local supplier at around 20 to 120Eur/year.
German article, but some translation tool might help: https://www.tagesschau.de/wirtschaft/verbraucher/waermepumpe...
But there are other factors as well. Air to Air heatpumps are uncommon in Germany, we usually install Air to Water ones, which are more complex. Unlike other countries, our heat pumps are usually mounted on a concrete slab and not on the wall. Then there are some norms for quality of the water, etc. they aim to increase the lifespan of the system, but increase upfront costs
And why do subsidies INCREASE the price in Germany compared to Sweden?
Here the upgrades for meters are paid for by the grid operators. No changes to the cabinets are required, old analog meters were replaced by them for smart meters, at no extra cost to the consumer, and now they will replace them with new meters capable of metering by 15 minute interval.
This cost in germany is really only created by overregulation and insane bureaucrats creating work for them.
I first heard that in Germany there is much resistance to smart meters and I thought they were just silly people, but if it costs so much..
Digital and Smart thats for othet countries.
I got air air heatpumps for 3 rooms 1000€ a room and it slashed my heating cost to 1/3. And I have to explain that its not foor cooling but for heating and then the response is " heatpumps are like 20k plus you liar" or " heatpumps dont work in the cold" ... germans
Still many people dont switch because the read somewhere about magic costs that dont exist. Russian Gas propaganda is big here
and this is a hugeeee house. No solar but he is working on it.
could you link some proof of this smartmeters I have to pay? Or some calculations from firms it whatever that proof your point.
It has nothing to do with smart meters. Some electrical installations are heavily outdated by today’s norms. And norms are obviously written by greedy suppliers of the cabinets and parts for them. Worst thing is that I can’t make any money by selling this stuff. It’s already too expensive for the people. And it will not be cheaper with Paragraf §14a EnWG.
UK heat pumps are half the cost of German installs 14k Vs 28k euros.
Theres multiple reasons given:
https://www.pv-magazine.com/2025/03/13/heat-pumps-in-germany...
Also, I believe Octopus have nearly halved the UK price since that report by optimising installs.
Not saying it makes sense, though.
And the fine is nonexistent so everyone should do it themself.
Do you risk to lose house insurance in case of issues?
This is one of the reasons why sometimes I am even afraid of thinking about such DIY projects.
Home PV for example is way less than 0,3€/kWh and rather dramatically changes these comparisons.
Going to sell for 10x when the water wars commence.
Because:
It is not experimental (it is no longer 1992)
Your gas comes from Russia, and they hate you - roughly speaking
Your prices are miles from reality
Face it, fossil fuels are deprecated. Your gas heating will be unusable with no gas to put in it
(From another post I made in this thread)
Looking at IMF 2025 GDP per capita figures (https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi... ):
Norway: $92k
Denmark: $77k
Sweden: $62k
Germany: $60k
UK: $57k
Finland: $56k
So yeah, Denmark and particularly Norway are a bit richer than the others, but the others are in the same ballpark.
If you choose between heat pump and not-heat-pump electric heating, it is cheaper.
To me, living in US Northeast, this is astounding. I've read heat pumps lose efficacy below 25F. My family would never forgive me if I made our house cold. But then I see 70% of the Nordics's house are "warm enough", or dealing colder than room temperature houses.
I've asked half-dozen contractors and HVAC people in my area, and none of them have recommended a heat pump. But, I'm just as suspicious of their motives as I am of the science and environmental populizers on YouTube.
Similarly for small houses the cost of the hole drilling might not be worth the reduction in electricity consumption.
In theory peltier elements are more efficient heaters than resistive heating but if the temp delta are big enough, you lose more heat through conduction than you pump in.
A poorly optimized fireplace may vacuum more warm air out than it radiates in.
January temps in Oslo aren’t much different than Boston. Absolute record low temps are similar too.
Coldest temp ever in Oslo is -30C in the 1800s.
Coldest in Boston was -28C in 1934.
Still doesn’t explain the poor adoption in USA but helps explain why they still work so far up north. The nordics can be relatively balmy to Wisconsin or upstate New York.
These remain 200% efficient down to -4℉ and 150% efficient down to -22℉. Their capacity starts dropping at 23℉ going down to 76% capacity at -13℉.
There's only a few towns in the continental US that cold enough for long enough that it can't be heated well by one of these. You just need an installer that will size it properly for the climate in your area.
IIRC in the Netherlands people don't like it, because it because it means that there is a single company supplying my heat, with
* minimum amounts of 'heat' purchased
* no incentives to maintain their infrastructure above the bare minimum
* no competitionThe heat source of the network is gas or various oil fuels, so it makes sense that it's cheaper to do it yourself - gas infrastructure is very optimised, and there are very little network losses in comparison. I think it only makes sense if the network has a cheap energy source, for example by using waste energy from industrial processes or utility-scale geothermal.
wouldn't untreated sewage, still fermenting, be warmer?
Interestingly enough the price for these giant heatpumps is pretty much in line with domestic ~10kw units.
https://www.wienenergie.at/blog/staerkste-grosswaermepumpe-m...
a bigger one is planned:
https://www.wienenergie.at/ueber-uns/meilensteine/2022-spate...
https://www.wienenergie.at/blog/fernwaerme-zukunft/#Abw%C3%A...
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.
And if it was really warm enough you wouldn't need heating in the first place.
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.
To be honest, I'm writing this comment mainly to say: what a great user handle, I smiled :-)
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)
Why do I have a feeling this is one of those "green" ideas that has some horrible environmental consequence. One that could have been solved with a way simpler technology for far less money in exchange for a bit of efficiency loss.
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.
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.
Not quite the same thing, but there is a tropical greenhouse in the south of France that used to be heated by cooling water from a nearby uranium enrichment facility: https://fr.wikipedia.org/wiki/La_ferme_aux_crocodiles (unfortunately not available in English).
You could get an even better result using the earth itself, but that is way harder to scale.
Browsing on mobile, I saw no way of contacting them about the mistake.
According to Google's built-in exchange rate calculator it should say $235m.
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.
A 1.6GWe nuclear reactor is around $8B.
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?
(It didn't last very long and was shut down in the mid 1970's, for somewhat obvious reasons.)
[0]: https://en.wikipedia.org/wiki/%C3%85gesta_Nuclear_Plant
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).
But unlike these heat pumps, the reactor doesn't need electricity.
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!
Even Germany had Uranium mines in the Erzgebirge. They just were closed due to environmental concerns and the iron curtain falling, which is also why there are no more "official" reserves. There was no exploration done after 1990, so known exploitable reserves in Germany are low. But that's just because nobody went looking.
Uranium isn't rare and it isn't really expensive. We just need so little of it that there are not a lot of running mines.