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Oxford study proves heat pumps triumph over fossil fuels in the cold::Published Monday in the scientific journal Joule, the research found that heat pumps are two to three times more efficient than their oil and gas counterparts, specifically in temperatures ranging from 10 C to -20 C.
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Heat pumps are A/C in reverse. It makes total sense instead of using fire to heat air.
brb putting in my window unit from the outside
You’d need to collect the condensate, but that would actually work quite well.
Also most of the electronics on the cold side aren’t designed to be exposed to the elements, so that would be a problem
You think you are being a smartass but that’s exactly what heat pumps do. The only functionality difference between an AC unit and a heat pump is a reversing valve.
But without a reversing valve you could put your AC unit in backwards and heat your house in the winter.
The whole premise of an AC unit is to take the heat from inside the house and put it outside, leaving you with cooler air inside.
So in the winter a heat pump simply reverses the flow of the freon and moves the heat from outside to inside. Yes. You are “cooling the whole neighborhood” when you run a heat pump.
I wish it was standard to be able to do both. My heat pump is unreal efficient and cheap and great but I’d love a cool breeze every now and then.
It definitely can. If yours can’t then it’s likely just the thermostat wired wrong.
It’s underfloor heating, the units that do both are more expensive so there must be something different.
Ah yeah that’s a different story then. However I’ve never heard of in-floor cooling before. I wonder how effective it would be since heat rises? I think you’d just have a cool floor and hot muggy air. Also the floor would condense water constantly so your floor would be slippery and if you have carpet it would be wet / damp constantly.
It’s a thing but you take really can’t cool down a lot due to the reasons you mention.
WELL FUCKING OBVI-
Oh right, I forgot some people are really pulling for this fossil fuel think to pull through.
Maybe someone can help me answer this question as I’ll be replacing my old furnace in the near future and am curious about the heat pump systems.
Studies like this are only looking at efficiency and not total energy usage or heating capacity so how do you compare apples to apples? A high efficiency forced-air furnace using natural gas is something like 95% efficient, and a heat pump can be something like 150%-200% (because you’re moving the heat instead of creating it), but the total output capacity matters as well as the efficiency of generating and transmitting the electricity. Also, I don’t think the power needed to run the fans gets factored in from what I can tell and I expect a heat pump system to need fans running far more often and for longer. Since heat is constantly being lost to outside then whichever can work faster might have an advantage keeping ahead of that entropy too…
I’m living in a climate considered “extreme cold” in this study btw. Best I’ve been able to figure out, a gas furnace is still much cheaper to install/operate (it’s pretty cheap here) but is also still be better for the environment as my electricity tends to be generated primarily from natural gas and coal (at an efficiency lower than a natural gas furnace does).
If you are comparing gas to heat pump efficiency, it is more like 85-90% vs 350-500% efficiency.
Because in the gas furnace efficiency they only calculate the efficiency of burning gas but miss to include the auxiliary electricity that is needed to run the system.
In a heat pump system everything (running fans etc.) is included in the efficiency calculation. The efficiency itself is depending on the source of the heat pump. In a really harsh climate a ground / geo thermal source might make sense. But usually the average temperature is higher than you might think.
And for the environmental effect: modern gas power plants run at 50-60% efficiency so with a heat pump you are always burning less gas even if the gas plant is less efficient then the gas furnace.
It would be interesting to know what extreme cold means.
That’s a good point about the furnace fan!
This commentary focuses on the performance of air-source heat pumps in mild European winters with average January temperatures above −10°C. We refer to these heating conditions as “mild cold climates”, whereas those with average temperatures below −10°C in the coldest month are designated “extreme cold climates”.
I’m using what the study calls extreme cold, which would account for about 3 months of the heating season where I live, and that’s where I got the lower efficiency numbers from too as they state the COP is around 2.75 (roughly 3 months of the year here) in the “mild cold” and only around 2 at best in the colder months.
We have a bit of an unusual climate here with fewer people so most of the info I find tends to focus on where more people live and the climate is different so it’s tough to figure out. There’s a good three months where no heating is required at all (and increasingly, ac units are in demand). A couple of years ago we had close to an 85°C temperature swing from the end of February to mid June!
Natural gas is plentiful and cheap so it’s used for central heat and hot water here, sometimes clothing dryers too but that’s less common. I still end up paying a gas bill in the summer months essentially just for admin fees and such, so the temptation is to go fully electric (would have to change the HWH) with a heat pump system and resistive backup heat. The problem is from what I can tell, the additional cost isn’t quite worth it yet (the system might not even save any money and is more expensive to install/maintain), and the emissions difference is tough to calculate when a third of the power comes from coal and over half from natural gas…
You’re right to be concerned about emissions, if you live in a place where a significant portion electricity comes from coal its almost certainly cleaner to just burn the natural gas. Which area of the world is this if you don’t mind saying?
I’m in Alberta (Canada)
Haha yeah that would do it. Even here in Ontario we still have a lot of houses with gas hookups despite our clean and (relatively) cheap electricity, but I see more ads for heat pump installs now so it’s definitely changing.
For sure look into any subsidies available to you and see if they make a dual fuel system feasible. In your situation if you buy a high efficiency furnace, it may never make economic sense to run the heat pump, but things could always change and it’s a simple enough task to find your break even (economic balance) point when fuel prices change. My current break even point is well beyond the temperature you would consider running heat, but I still run my heat pump in the shoulder seasons to exercise it.
create energy
Ummm… that’s not how it works.
They actually added a correction at the end for that
I don’t know that we really needed a study for this. You can find the COP vs temp vs capacity curves for every heat pump out there. This will tell you exactly how many BTUs of heat the pump will produce given a watt of electricity input. I guess they were just validating that the curves were accurate?
Here in Massachusetts, the belief is that heat pumps do not heat well when the temperatures reach 0F
That’s -17.8 C, so pretty close to the limit mentioned here
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People think that’s a killer argument against heat pumps when it absolutely isn’t.
In that sort of climate you get a hybrid system or just leave your old furnace in as backup. You’ll use the furnace for the couple of days/weeks when it is below -25c/-13f and use the heat pump for the 6 months around that time window and save huge amounts of energy because you only use the heat pump when it’s most efficient. A hybrid system will improve efficiency because it combines the technologies at transition temps while just keeping the old furnace as backup is obviously much cheaper, since you can also get a smaller unit than you normally would because you don’t have to worry about the coldest period.
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Okay, I suppose you wouldn’t do that when replacing and old furnace but rather go for a hybrid system. In Europe loads of people are reacting to hiked gas prices and have perfectly fine furnaces in place that they don’t want to get rid of.
You might not be totally out of luck:
- More modern units do pretty well down to -20f.
- Ground-source systems don’t care about air temps (but are more expensive)
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what the fuck
(sorry I live in Australia and that is shocking)
I believe you meant “what the fuck, cunt?!”
Be proud of our heritage, mate.
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I don’t think Siberia counts as a place where people want to live.
Yowsa! That’s cold.
That said, ground-source systems have been used to good effect in climates like that! But, of course, do what’s right for you 🙂
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Which is the absolute minority on that regard, most people live in climates where it doesn’t get that cold.
it doesn’t get that cold.
For now.
I’d also add that like, for a lot of Scandinavia heat pumps work just fine? Like does America just have some really bad heat pumps or something?
I think the only reason why you wouldn’t install one here (aside from obvious cost issues) would be if you already have a robust heating system built into your home, like a hot water system. And if that’s the case, you can use the heatpump of the earth - geothermal! Use the power of the earth’s molten core to heat and cool your home!
(… geothermal isn’t as ubiquitous as I make it sound it’s just, really fucking cool)
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1.25% of population. The minority point stands
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Really? Where in the US or Canada do tens of millions if people live with AVERAGE winter lows of -25F?
Fairbanks AK seems to be widely regarded as the coldest US city, and that is -15F average lows. If I move to Prudhoe Bay on the northern coast of Alaska, then in find the -25F low I’m looking for. 
A quick search suggests Winnipeg is the coldest major city in Canada, and it doesn’t quite reach -20F average. There are of course some more remote towns that get colder; Canada goes pretty far north.
Like consistently? Or just one or two days a year? Because I feel like bringing out the electric heaters a few times a year is way better than just giving up and using fossil fuel all the time
Also I’d mention that heat pumps are super common over here in Scandinavia so I have my doubts that it’s an issue with the medium and not something else. Maybe you guys have like, heat pumps that are more designed for the heat rather than the cold?
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How cold? Also heat pumps can have auxiliary electric heat strips, maybe even auxiliary natural gas.
Not in January in Central New Hampshire.
They work in Sweden… and Canada…
Sure it does. Unless your average temp in January is under 5F? And on those really cold days the gas furnace kicks in anyway, so you get the most efficient heating no matter what.
So you still need a gas furnace…
A/C guy who’s the son of an A/C guy here. Heat pumps lose efficiency the colder it gets. I wouldn’t bother with one if you’re in a northern climate. Lower midwest, you might be able to save money with a heat pump over natural gas, but it will depend heavily on the cost of the respective energy. For me, in the central US, we have great prices on gas and somewhat crappy prices on electricity (vs most surrounding regions) and it’s definitely cheaper for me to stick with gas heat.
So this is exactly what the article is about and up to -4 f heat pumps are more efficient.
If your the son of an hvac guy maybe your information is based on older installed units. I had a heat pump installed in my fathers home in the northeast ( non coastal) and I was shocked it ran well all year. I had heard the some rumor that you had.
Technology advanced and facts change.
Your information is outdated. It is even clearly mentioned in the one-sentence summary in the OP:
Oxford study proves heat pumps triumph over fossil fuels in the cold::Published Monday in the scientific journal Joule, the research found that heat pumps are two to three times more efficient than their oil and gas counterparts, specifically in temperatures ranging from 10 C to -20 C.
That doesn’t say anything about gas prices.
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And the naysayers don’t actually run calculations to see what their true costs might be, they already decided gas is king. A couple of good ol boy type HVAC folks that all say “just get a furnace” is all they need to know, reality be damned.
its hard to get a person who living is based on a lie to see the truth.
Well my gas is only 3 times cheaper currently before the Ukraine war it was 6-7 times cheaper so…
This is the correct take for a conventional heat pump. However, there are relatively new geothermal heat pumps that can heat down to -30°C (-22°F) and are much more efficient.
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Thankfully heat pumps have gotten better since your father’s day. And natural gas is only going to keep getting more expensive. For a price of equipment that will last you 15-25 years it’s becoming harder to justify gas heating.
For new builds ground source heat pumps should become more standard, they cost more, but they’ll save a lot in the long run.
But its all irrelevant because the most effective way to keep warm is to continue with global warming. Soon we wont have a cold season to worry about. 😜
I know you’re joking but the reality is we’ll probably get worse cold weather alongside the warmer weather - the weather will be more extreme at either end.
Scary, isn’t it?
Yet there are still people out there denying it.
Continue? You can’t stop it even if you wanted to, unless you pervert the natural climate cycles somehow. We are exiting a cold period and it has nothing whatsoever to do with using gas or come farts.
You mean this natural climate cycle?
[After setting your car on fire] Listen, your car’s temperature has changed before.
Oh fuck! Are you a climate change denier?! Are you joking, too? or do you still believe this is a natural change?
The climate changes. There’s no denying it. No it isn’t caused by cow farts so everyone needs to? eat bugs instead, and no it isn’t caused by driving your car so you must become a serf and be bound to your lords 15 minute plantation.
Dont know what happened, but i can’t see this comment thread anymore. Maybe it’s been deleted.
Whatever happened, you are absolutely full of shit.
Maybe you should try listening to scientists instead of talking about cow farts. There is an insurmoutable amount of information and proof that the climate has warmed drastically in the last 20-100 years and it doesn’t follow any recorded pattern of warming and cooling since the dawn of humanity ~200000 years ago.
Heres a nice image showing the data in simple terms.
You xan continue to dwny it all you want, but any rational person will ignore you.
Incidentally, dont pay attention to mass media, i hear a claim i look at the facts and draw my own conclusions. You should do the same.
If you’re on propane, it’s more likely to be cheaper. Particularly over the course of an entire heating season, because they’re more efficient in fall and spring than the coldest part of winter.
But yeah, this study wasn’t looking at cost per therm but just raw COP, which is a pointless metric. It doesn’t even compare the number of watts of heat from burning natural gas in a furnace vs in a modern power plant that supplies a heat pump. Although since we don’t have a carbon tax, that’s only a theoretically interesting comparison.
Heat pumps work fine for most people in the north. Mitsubishi’s cold climate heat pumps supply 85% of their rated heat at -13F. Buffalo is a city known for its winters, and the last time Buffalo’s lowest temperature was below that was 1982. They’re just going to be a more expensive option for most people right now.
Well, some people don’t put money higher than the ability of humanity to survive.
So the cost is less relevant than the pollution.
My father in law went to a heat pump instead of propane this year. No natural gas where he lives.
But he also dropped 20k on a solar system to power it.
How long would the return on cost savings take for it to pay itself off?
Ditto. At least with gas I’m not paying Alabama Power’s rates.
If you posted that earlier today you would have gotten a spanking for saying anything critical about heat pumps. Or people just don’t like me in particular. Hard to tell.
Maybe your information was just not factual?
