Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The biggest heat pumps

bbc.com

Post reply on HN
Print view View original

91–100 of 197 posts

Re: The biggest heat pumps

#91

Post by Phenomenit »

jgalt212 wrote: post #87
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…

> Something like 70% of houses are heated by heat-pumps 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 h…

You never go below 1 in efficiency. Worst case the water is heated directly with electricity.

Re: The biggest heat pumps

#92

Post by jimmaswell »

xg15 wrote: post #85

A bit OT, but since this article also mentions district heating: Are there any efforts to attach any of the recently built AI data centers (and their power plants) to district heating networks?

If we all went full-in on nuclear we could use resistive heat and air cool datacenters all day with no concern for the cost. It's a shame.

Re: The biggest heat pumps

#93

Post by renhanxue »

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…

Heating with gas is absolutely not a thing in Sweden, I don't think even a single percentage point of homes use that. Firewood is way more common (it's relatively commonplace in the countryside still). Gas is used for stoves in some older buildings in a few specific cities but is almost extinct in that application too. Heating with gas hasn't really been a thing historically either - at first it was mostly wood, then coal and wood, and then district heating and fuel oil completely took over from the 1950's. For a while in the 1970's resistive electric heaters were popular because electricity was cheap with the then-new nuclear plants, while the oil crisis made oil expensive. That didn't last very long.

Re: The biggest heat pumps

#94

Post by 1313ed01 »

looofooo0 wrote: post #35
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.

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.

Sweden used to have very cheap electricity. That's why there are so many houses with electric radiators. Far more expensive now.

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.

Re: The biggest heat pumps

#95

Post by bratwurst3000 »

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.

Did the same. air air is cheap and works like a charm. this 40k for heatpump is for the most luxury version every salesmen trys to sell

Re: The biggest heat pumps

#96

Post by jabl »

renhanxue wrote: post #90
jgalt212 wrote: post #87

Earlier quoted context omitted.

> Something like 70% of houses are heated by heat-pumps 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 h…

A lot of the Nordic heat pumps are ground source, that is to say you drill a hole a couple of hundred feet down into the bedrock where it's always a bit above freezing and you circulate your heat exchange fluid down there and back up again. Air-source heat pumps are mostly a thing in the southern parts where the climate is relatively mild.

Air-source heat pumps are also somewhat common in retrofits where the remaining expected lifetime of the building isn't big enough to be worth spending some 20-30k€ (?) that installing a ground source heat pump costs. A significant part of the cost being drilling the hole.

Similarly for small houses the cost of the hole drilling might not be worth the reduction in electricity consumption.

Re: The biggest heat pumps

#97

Post by renhanxue »

Those are some big heatpumps, but in terms of installed capacity at a single location they have yet to beat the Stockholm municipal heating utility's installation at Hammarbyverket, which since its most recent expansion in 2013 has a total of 7 heat pumps capable of extracting up to 225 MW of heat energy from treated sewage. The utility claims it is (still) the world's largest heat pump installation. Notably it actually uses both the hot and the cold side of the heat pumps; the cold side is sent into the district cooling network.

Re: The biggest heat pumps

#98

Post by MisterTea »

sowbug wrote: post #80
MisterTea wrote: post #75

Earlier quoted context omitted.

> 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

My only caution is this method does not let you check if the lines are leak tight.

Re: The biggest heat pumps

#99

Post by cyberax »

masklinn wrote: post #26
cyberax wrote: post #17

So $235 million for 162MW, or $2.35B for 1.6GW A 1.6GWe nuclear reactor is around $8B.

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 Tai…

I'm just comparing the magnitudes here. A nuclear reactor powering dumb cheap resistive heaters is just several times more expensive than the heat pumps.

But unlike these heat pumps, the reactor doesn't need electricity.

Re: The biggest heat pumps

#100

Post by vintermann »

Retric wrote: post #84
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…

40k for heat pumps is wildly overkill here if that’s what you where quoted someone is trying to scam you. More critically, those prices aren’t set in stone over the next 30 years. Home PV for example is way less than 0,3€/kWh and rather dramatically changes these comparisons.

If we only could get China to do for heat pumps what they did for solar panels...
Post reply on HN