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The biggest heat pumps

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Re: The biggest heat pumps

#171

Post by sokoloff »

stefanfisk wrote: post #153
moooo99 wrote: post #148

Earlier quoted context omitted.

The biggest factor is almost certainly the subsidy for switching to a heatpump. 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 th…

AFAIK we do all of that in Sweden. The 12k I mentioned above is if a large air to water pump suitable for the northernmost of Sweden. It includes a water heater and direct electric heating element for when temperature go below -15. And why do subsidies INCREASE the price in Germany compared to Sweden?

In the US, the subsidy is paid only when the heat pump is installed by a certified contractor. Unshockingly, the certified contractors are able to capture the vast majority of the subsidy as additional profit.

Re: The biggest heat pumps

#172

Post by sokoloff »

wolvesechoes wrote: post #129
wkat4242 wrote: post #29

Earlier quoted context omitted.

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…

> more insulation Nothing to do with a heat source.

Not directly with the heat source, but with the output flow temperature that the heat source can create.

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.)

Re: The biggest heat pumps

#173

Post by jaapz »

wolvesechoes wrote: post #129
wkat4242 wrote: post #29

Earlier quoted context omitted.

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…

> more insulation Nothing to do with a heat source.

In the netherlands we were used to really cheap gas (groningen gas field). This meant that, instead of adding more insulation, it was cheaper to just install a bigger gas powered heater to heat our homes.

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.

Re: The biggest heat pumps

#174

Post by ZeroGravitas »

stefanfisk wrote: post #44
lnsru wrote: post #38

Earlier quoted context omitted.

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…

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...

Octopus and a German University did a report on costs.

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.

Re: The biggest heat pumps

#175

Post by mk89 »

xeromal wrote: post #79
lnsru wrote: post #38

Earlier quoted context omitted.

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…

I installed mini splits (small heat pumps) in each of our rooms. Everyone gets their own temperature and they were only 800$ a piece. Did installation myself and it was pretty easy. Hardest thing was pulling a vacuum in the lines before releasing the freon (or whatever it's called) but all I did was watch a youtube video. They've been going strong for several years. I looked at the prices and they are still the same.

BTW, in Germany you're not allowed to install it yourself. At least that's what I read some time ago. I guess nobody checks, of course, but in case things go bad and you need insurance, probably they can invalidate it due to the fact you did something illegal.

Not saying it makes sense, though.

Re: The biggest heat pumps

#176

Post by sokoloff »

sokoloff wrote: post #170
seec wrote: post #167

Earlier quoted context omitted.

Isn't the problem having access to the gas in the end ? They are tightly regulated, and this is why installers can charge a lot of money, I believe. How did you manage to locate a source?

For a typical new install, the outdoor unit contains the charge and unless your lineset is unusually long, you just use that, releasing it with the valves after installing and leak-checking the lines. 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…

s/508/608/

Re: The biggest heat pumps

#177

Post by triceratops »

looofooo0 wrote: post #158
triceratops wrote: post #101

Earlier quoted context omitted.

It's the year 2135. Discussions about energy anywhere in Europe begin with the customary lament for Germany's shortsighted decision to cease nuclear energy production sometime in the 20th century. Nobody knows where this tradition originates from but it is rigorously upheld.

You mean if Germany still exists and the mongols did not have take over Europe.

I think they know how to deal with horse archers now.

Re: The biggest heat pumps

#178

Post by UomoNeroNero »

holowoodman wrote: post #76
pjc50 wrote: post #69

Earlier quoted context omitted.

Why is that required? Switch to three phase? Wasn't required for me in the UK.

No. Everything in Germany has been three-phase since forever. 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 m…

Ok. For once, I’m glad to be Italian :-D Here the national grid operator has installed smart meters. They support remote management of limits (maximum power in watts, tariffs, time-of-use tariffs), remote meter reading by the operator or local access plus an app, remote diagnostics, and simplified installation (strict rules and operator intervention, but in the end nothing particularly complex).

Re: The biggest heat pumps

#179

Post by mrmlz »

wkat4242 wrote: post #70
pjc50 wrote: post #59

Earlier quoted context omitted.

Not many people left with single glazing unless they've been trapped by historic building rules. "Outdoor plumbing" is not a thing. 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.

Not sure about the UK. I've seen a lot of outdoor plumbing in Ireland. I lived in a place that had that. They were literally running on the outside. Our maintenance guy said they did that to make maintenance easier, but it also makes wear & tear a lot easier obiously (not to mention frost). And chipboard floors that would crack with heavy furniture. It was terrible quality. These houses were built in the mid 80s. And…

Yeah i feel like the other answers tries to gaslight me and downvoting to hide the ugly truth! :)

Would you say modern (i.e. <10 years) are properly insulated and built or are there still... shortcuts?

Re: The biggest heat pumps

#180

Post by seec »

sokoloff wrote: post #170
seec wrote: post #167

Earlier quoted context omitted.

Isn't the problem having access to the gas in the end ? They are tightly regulated, and this is why installers can charge a lot of money, I believe. How did you manage to locate a source?

For a typical new install, the outdoor unit contains the charge and unless your lineset is unusually long, you just use that, releasing it with the valves after installing and leak-checking the lines. 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…

Yes, in the US I think it's fine; you have a lot more freedom.

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…

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