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The biggest heat pumps

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Re: The biggest heat pumps

#71

Post by zzbn00 »

hexbin010 wrote: post #27
willvarfar wrote: post #14

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 co…

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…

This is exactly the thing. In UK electricity price is set by the cost of generating it from natural gas. After losses, etc, you get about 1/3 of power in electricity compared to heat in the gas. And the heat pump has an efficiency factor of about 3. So you get back to unity.

While electricity is priced off gas, current heat pumps do not have a strong economic case.

Re: The biggest heat pumps

#72

Post by pm215 »

supersparrow wrote: post #50
mrmlz wrote: post #40

Earlier quoted context omitted.

UK houses are really interesting.. Single-glass windows, poor insulation etc. And plumbing on the OUTSIDE(!) :) 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..

I’ve lived in the UK for 35 years and lived in various properties built in every decade from 70s-10s. Some much older and less loved ones did have single pane windows but have never seen plumbing on the outside. Maybe on much older houses? Certainly not on anything remotely new. A lot of new builds here have solar, heat pumps and insulation has been excellent for at least 20 years.

You do relatively commonly see wastewater piping on the outside of a house in the UK, especially older stock (soil stack from the toilet, waste pipe from sink or bath running into it). This is fine in the UK climate where a normally empty pipe doesn't need insulation. I hear that it won't work in places that get extreme low winter temperatures, but the UK doesn't have winters that cold.

You don't see them on new builds, I think, probably because the pipe going from inside to outside would reduce insulation effectiveness.

Re: The biggest heat pumps

#73

Post by MrBuddyCasino »

Maledictus wrote: post #48
looofooo0 wrote: post #42

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.

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.

This problem could have been solved by breeder reactors. Now China is doing it instead of us.

Re: The biggest heat pumps

#74

Post by zzbn00 »

hexbin010 wrote: post #52
supersparrow wrote: post #46

Earlier quoted context omitted.

A boiler should actually be lasting more like 20 years. I recently replaced my 20 year old one purely because if anything went wrong, it’d become an expensive/long job to fix as parts were hard to find, otherwise it was still running perfectly at its manufacture specified efficiency. Running them for 20 years isn’t uncommon. I had a quote for a heat pump - £20k, plus the cost to replace 13 radiators, plus cost to rep…

Was your old boiler a non-combi? 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!

Condensing boilers became mandatory in UK just over 20 years ago

Re: The biggest heat pumps

#75

Post by MisterTea »

Ekaros wrote: post #33
jack_tripper wrote: post #24

Earlier quoted context omitted.

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.

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.

> There is install, but even that is not really that significant.

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.

Re: The biggest heat pumps

#76

Post by holowoodman »

pjc50 wrote: post #69
lnsru wrote: post #68

Earlier quoted context omitted.

State subsidies and insane overregulation. Think about replacing the cabinet for electricity meters (+4000€) for heat pump installation.

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 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.

Re: The biggest heat pumps

#78

Post by jwr »

Maledictus wrote: post #48
looofooo0 wrote: post #42

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.

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.

That is such a bad explanation. One, Russia is not the only supplier, two, Germany still buys fossil fuels from Russia.

Re: The biggest heat pumps

#79

Post by xeromal »

lnsru wrote: post #38
moooo99 wrote: post #28

Earlier quoted context omitted.

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.

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.

Re: The biggest heat pumps

#80

Post by sowbug »

MisterTea wrote: post #75
Ekaros wrote: post #33

Earlier quoted context omitted.

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.

> There is install, but even that is not really that significant. 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 n…

There is now an even easier way than vacuuming. Instead of pulling the unwanted air and moisture from the lines, you can push it out with another gas, which itself can somehow coexist with the refrigerant. I haven't tried it because I already have the pump and gauges, but if I were installing my first mini split, I'd consider it.

Example: https://www.highseer.com/products/pioneer-kwik-e-vac

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