Heat pumps can’t take the cold? Nordics debunk the myth::By installing a heat pump in his house in the hills of Oslo, Oyvind Solstad killed three birds with one stone, improving his comfort, finances and climate footprint.
It never ceases to amaze me how people don’t read past the title 🤦 There are people debating about -10 to -30C when the article clearly states that it works in those temperatures. Not only does it work, it’s twice as efficient as electrical heating at those temperatures.
I think it does, and it seems to work because of a defrosting feature that earlier models didn’t have. But I wouldn’t say it does so very clearly. Unless I missed it.
Good Lord - $2600 for a whole house system? I think that’s what my local (mid-Atlantic US) HVAC shop is getting for a single-room mini-split.
Wait until people find out about ground-source heat pumps and water heater heat pumps. What you get out of those is more consistent year round, too. It’s almost like leveraging technology has benefits over just burning carbon and hydrogen to make heat.
I got a quote in rural America for a single room minisplit, $10,300.
Absolutely bonkers.
That is absolutely bonkers. I put one in myself for my one room garage that I converted to a place to hang. Cost 720$ after tax for a Pioneer mini split. It’s entering its third year in use and I love it. That being said, I wouldn’t be so risky as to put my own in when its task was heating or cooling my home. Just my garage is my problem, the rest is my family, and so I paid. But I got a whole home solution, two floors, Carrier units, for about $15k.
I believe what you’re looking for is out there and not ridiculous price.
Also in rural America. How did you get someone not to laugh at you when you asked? God I fucking hate the small mindedness around me, but I couldn’t stand the city either. I cannot find someone to put one in my house so I’m going to have to install it myself next summer.
Yeah, no. German here, if your house already is all prepared, ideally with large radiators or heated floors and you really just have to switch out the source of heat from whatever to a heatpump, then you’re maybe looking at 15k€ including work. The man probably collected a properly dimensioned subsidy.
You’re just repeating what all the gas installers keeep repeating so they don’t lose business.
Every House built after 1990 or houses that have had insulation makovers in the past 20 years are perfectly fine to heat with a heatpump.Yeah, I know, I have a heatpump. However, it’s just working so well at about a COP 1:4 at the moment because I’ve got flow temperatures of less than 30°C due to heated floors. If I needed 50°C I’d be down to about 1:2.5 right now and that’s not cost saving anymore compared to gas.
And I’ve checked, my exact model costs about 13k€ right now, make that 2k€ installation costs and we’re not far off.
$2600 is utter bullshit. I had several quotes for a 1000sf house, not a single one was under 16000 installed, after rebates. My payback period was going to be almost 20 years even against a medium efficiency gas furnace.
Even the Diy mini splits, you’re paying $600 to $1000 easily for just one single unit.
Paid $6700 in May to replace mine.
I don’t think Geothermal makes much sense unless you live in one of the extremes, mainly the cold one, For example I an from Slovakia and I don’t think the temperature here went under -20C in the last few years, I barely remember any days going under - 10C, so you would be paying quite a premium for a geothermal heat pump for rather marginal gains, it would certainly need quite a good analysis if the difference in performance would ever pay for the price difference, especially with better insulation and heat recuperation systems becoming mandatory.
There are also things like heat pump based driers now on the market btw.
I suspect it’s mostly a function of mass availability. Even here in the states ground source heatpumps are rare, even though the systems are more reliable (since there is no equipment exposed to weather) and a shallow borehole isn’t excessively expensive.
I’d forgotten about heat pump clothes dryers. Those are fascinating, and really interesting for older buildings or locations without close access to exterior venting.
Wow that’s really pricey. Here in Malaysia a 2 HP mini split with inverter costs roughly RM 2400 including installation (around $500).
Granted the average salary here is much lower but it’s amazing how much the prices differ given that they all basically come from the same factory.
Hell yeah, we’ve got a heat pump and we’re in Canada where it can get to -40°C (which is coincidentally also -40°F) and that thing works like a beast. Fortunately we also have the cheapest electricity in North America so the decision was easy.
What’s your heat pump? I’ve been looking into them and I can’t find one that’s willing to say it works past about -15.
The Mitsubishi Hyper heat can work down to -13F, The absolutely best resource I’ve found for heat pump research is the NEEP database which will you give you actual BTU outputs at various ambient temperature readings: https://ashp.neep.org/#!/product_list/
 Also worth considering a geothermal heat pump depending on your geography, as then you have a guarantee of efficiency all year roundSecond the NEEP database. I’d just add that the lowest temps listed here aren’t the actual equipment minimums - each model has a cutoff temp where it will literally shit the bed (except ground source of course). For my mistu hyper heat, it’s -26F. Capacity will keep dropping after -13F though (where it’s still at like 80% I think).
Can you just start saying “America” that way it includes south America and Central America, also?
But that wouldn’t be accurate because there are South American countries with even cheaper electricity than here, so it’s only the cheapest in North America.
Also not to be too pedantic but central America isn’t technically a continent, and it all falls under North America anyways.
It depends on the model (and the price), I’m in Québec where we have -30°C (-22F) about every winter, my heatpump is mid-range, and works fine until -20C (-4F) so 95% of the time. It is set to 23C (73F) and it’s between 21-23 everywhere in the house. The electric baseboard are set to 21C (70F) as backup.
So yeah, heat pumps can works great in winter, no problem.
Also as written in the article, with defrosting and variable speed compressors, it is very efficient. Mine is Energy Star compliant, and act as air conditionner in summer.
Makes sense to me that they could theoretically work all the way down to near 0 kelvin, just depends on their efficiency. Just so long as there is heat to be had…
Also, not sure energy star really means much.
They theoretically could, but the coefficient of performance would go below 1 long before you get close to zero Kelvin. That means it would cost more energy to pump the heat than is pumped, so you’d be better off using an electric heater.
Ah yes… that’s a very good point. I’m not about to learn a bunch of chemistry and physics and stuff… but I’d be interested in reading about this theoretical optimization if electricity was free, there was no gravity, friction was 0, etc etc etc.
my heart goes out to the three little birds
Feast your heart on this:
Better than 15 birds in 5 fir trees.
Their feathers were fanned by a firey breeze
How is this a myth? Nobody with more than two braincells thinks that heat pump heaters don’t work in the cold.
If we start comparing everything that idiots think to a mythological mystery worthy of note, we’ll be here for an eternity.
This is not a myth but a fact, heat pumps don’t work at extreme cold temperatures.
What temperature exactly depends on the coolant used.The efficiency also degrades at lower temperatures.
This is a random example of first hit I got on a heat pump.
https://heatnow.dk/produkt/altech-sirius-9-varmepumpe/Notice the effect drops dramatically below -20 C°.
But this is a pump sold for the Scandinavian market, therefore it is of course designed to work at low temperatures. It doesn’t state the minimum, but I’m guessing it would be around -40 C°. Which is very good compared top older models.
But that’s not sufficient. As the temperature gets colder, it’s not just less efficient but produces much less heat. At the lower temperatures, it may not be able to keep up. Since it would be wasteful most of the year, heat pumps aren’t sized for that
IDK why you are downvoted, this is exactly true. The pump can only use it’s max power, and at max efficiency it generates 4-5 times that power in heat. But at temperatures below what the coolant allow, it only produce heat equivalent to the power put in, or a 4th to a 5th it’s max output.
Meaning the pump gets less efficient as it gets colder, and potentially will not be able to keep up in extreme conditions. As output goes down at lower temperatures, the same time demand for more heat increases.
The Heat pump shown however, does go very low, and it would be exceptional if the limit was reached. But just a decade ago, most heat pumps couldn’t go nearly that low, and lost efficiency quickly already below zero Celsius.
Despite that, the advantages with the newer heat pumps are still big enough for it to make good sense to switch to it for most, even Scandinavians.
Here in New England as far as I can tell, HVAC contractors tend to recommend hybrid systems, with a gas furnace as the secondary heat. However maybe that’s because gas is much cheaper than electricity.
Maybe there’s a contractor around who can give a better opinion on whether my experience is general
I never heard about that, here it’s very extreme if it’s below -20 C°, and new heat pumps can handle that, and remain pretty efficient.
I think the consensus here is to get rid of the gas. Despite we have it from the Nordsea, but the price structure is 100% dependent on the situation in Europe as a whole.
And Russia has fucked that up. So I don’t think anybody here is recommending gas for that reason. Although gas has already returned to be the cheapest option even here AFAIK, and prices have stabilized in part due to LNG from USA.
Same with EVs. Don’t work in cold weather. Except in the Nordics.
EVs work fine in cold weather. I live in Minnesota and drive an EV. It loses about 10-20% of the total range in the winter, but most of that appears to be from generating heat for the passengers.
I was being sarcastic. I’m from Germany and most “car people” constantly talk about EVs being not reliable, especially during winter …
Removed by mod
Gas cars don’t have a battery, they run on… gas
.
/s
The problem isn’t that EVs don’t work in the winter, it’s that their range gets significantly reduced. We had issues with people literally up and abandoning their vehicles because their batteries ran flat.
In these cases the issue is less that the range is lost, and more that with snowy and cold weather traffic gets unpredictable. You can end up in long queues and that’s where the issues start.
When I went on a work trip up in the far north I never saw a single EV. Asked my colleagues about it and none of them thought EVs particularly feasible as a primary vehicle.
All that said, EVs work great for most people most of the time.
I mean, it’s not about them not working, it’s the efficiency. Most models will switch to a normal electric heater, if they can’t extract anymore heat from the surroundings. At which temperature that happens, depends on your type of heat pump.
I want to understand what happens when it’s too cold out. And just running in pure air sourced HP mode, without supplemental heat.
Does it keep running at 100% but produces no heat? Limited heat? Does the house get colder and colder until everyone turns into a popsicle?
Or does it only heat the house to 18c instead of 20c?
In a climate where the low is -10c, how well does it work?
It gets less effective, down to running at 100% and not moving heat. Heat pumps work by expanding a gas, which cools it. Since it’s cold, the “heat” outside was the gas. Then the gas is taken inside and compressed, the gas heats up from the compression (since all the energy is squeezed into a smaller space, effectively speaking). Now that heat can be transferred to the colder air inside. So long as the expanded gas turns colder than the outside, it can absorb heat.
From a Google, common ones can go as low as - 25C, which means they are able to cool a gas to lower temps than that when expanded. There is still heat to get, even in -25C.
I can only talk for myself but I have a Nibe pump here in Sweden with air source outside pump and water heating system to radiators on the inside. Even down to -30° with really shitty windows it was enough heat for me to be comfortable. Though it did indeed use the supplementary resistive heating a bit it was still able to give me about a 200% efficiency during that period. Give a typical winter (usually around -5-10C but, as said can go down to -20C or -30C for a week or so) it still runs an average of about 300-400% efficiency.
So my question with heat pumps is more how much does humidity effect the efficiency? Where I live is high elevation, has cold winters, but the air is dry as fuck. Single digit humidity for a month wouldn’t be unusual.
My understanding is that heat pumps work best with humidity since moving moisture is part of how the heat is produced. When does a reasonably priced heat pump start falling off in efficiency?
They are just AC units in reverse. The biggest effect humidity is going to have is on how much condensation is going to form on the exterior radiator. That’ll form frost that’ll have to be melted in a defrosting cycle. That’ll decrease performance and efficacy. Low humidity should keep that to a minimum.
No that’s just my shitty heat pump. Sigh…
I bought into the heat pump hype until I bought a house with a furnace. Up until then I lived in apartments with heat pumps. I was stunned about how much better it was than any place I’ve lived before. It was used for it taking forever to get warm and always feeling colder than the thermostat would indicate. With a furnace it got warm quick, and it truly felt warm once it reached temperature. My power+heat bill was significantly lower per sqft than my power bill in my apartment.
I’ve lived in the Midwest, the Mountain West, and the South. I experienced the shortcomings of heat pumps in every place.
This article, which I believe to be geared at convincing US readers that heat pumps are great, also does some things that are extremely disingenuous.
For one, most heat pumps in Norway are geothermal heat pumps. Those are extremely different units that are well known to both be more energy efficient and function at much lower temperatures than air source heat pumps that are typically pushed in the US. The example where they interview a guy with an air source heat pump seems like an almost intentional misdirection.
Second, the author uses a comparison to electric furnaces. That has been widely known for years to be hilariously inefficient. As such it’s fairly rare to see in the US. The most common sources of heat in the US are air source heat pumps (in places like AZ and Texas), oil radiators, and gas furnaces. Depending on energy prices, these could be significantly cheaper depending on utility cost. I understand Norway has specific conditions that make oil and gas usage much less appealing but, again, this article is clearly targeted towards westerners.
I feel like this is EVs all over again. Heat pumps have a lot of potential. They will one day before the de facto standard almost everywhere. However they have serious shortcomings and the idea that they are ready to be a drop in replacement in the vast majority of cases is hopium.
EDIT: Since everyone is getting caught up over the word “efficient”. Electric furnaces are hilariously expensive.
For those reading wondering if this guy knows what he’s talking about, he says that electric furnaces are “hilariously inefficient”. They were in fact the most efficient option before heat pumps - more efficient than the most efficient gas furnaces. Electricity is expensive, so depending on the situation, it may cost more than inefficiently burning super cheap gas, but calling electric heating “hilariously inefficient” demonstrates a severe lack of knowledge of the area. So, with that in mind, consider whether anything else claimed here is worth retaining.
Fine. Electric Furnaces are hilariously expensive. Happy?
Compared to gas? Nope. They are not hilariously expensive. Gas furnaces cost more to purchase, install and maintain than electric, and they have a shorter life span. For some people, especially those with minimal heating needs, electric furnaces are most cost effective than gas ones. Again, more basic info you are unaware of.
Compared to heat pumps? Maybe. Ground source heat pumps have huge installation costs and although they are far more efficient it may not make up the cost for everyone. Air source heat pumps aren’t much more expensive than traditional options, but they’re much more efficient. If you’re in an area where an air source heat pump is an option, almost certainly it’s more cost effective.
None of this is what you’re saying though, that heat pumps are unproven, unready technology, which is bunk. They’re not an option for everyone, no option is, and they may not be the right option for you. However, they are an option for most people. If anyone is looking to replace a furnace they should absolutely consider an air source heat pump, and potentially should consider a ground source one.
Okay before I go further I need to ask the following questions:
- How old are you?
- What type of home do you live in?
- Do you own your home?
- What types of heating units have you lived with?
- Where are you located?
I don’t want to waste my time breaking down how wrong you are if you’re a 19 year old posting this from a college dorm.
You have this wrong. The problem isn’t the age of other people on the Internet. It’s that you don’t understand that anecdote and limited knowledge are not a basis for judging the feasibility of a technology or making conclusions about what’s useful for broad swathes of people.
Sure.
