Makes sense. Heat pumps are one of the few heating systems that can achieve greater than 100% efficiency. (energy in vs total heat output)
As long as you can keep the evaporator above the evaporation temperature of your compressed refrigerant, you’re golden. Burried lines are excellent for that in colder climates, but the space for it isn’t always easy to find.
It’s a little more expensive, but most places can find the space by drilling straight down. Still worth it from what I’ve seen in most places.
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The coldest temperature ever recorded in the UK is -27. That’s right around the inflection point for where heat pumps become less efficient than electric heaters. Until the gulf stream fails, the UK is pretty safe to use heat pumps everywhere.
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So yeah, going 100% air-source heat pump if you’re area regularly spends time around -30°C (-22F) might not be the best idea. Though even the last report you cited said it might be 1.5-2x as efficient as resistive heating. And that Site 1 with bad COPs was because they manually lowered the fan speed…
There are vanishingly few people who live in areas with weather consistently below -30C. I’ve been seeing that kind of concern trolling all over the place in the past year or so, and they always have the same song and dance about low efficiency in extreme cold - technically correct, but taken as part of the bigger context, so niche as to be practically irrelevant. Yeah, if you live in Yakutsk you won’t want to rely only on a heat pump. Big fuckin’ deal - the other 99.5% of people on earth can benefit greatly.
Edit: I wouldn’t be susprised if this is the exact same guy I once argued with on Mastodon, actually. He was German too.
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I’ll chime in here since I own 2 heat pumps and live in a cold climate (often below 20C). Our house is heated with 100% electricity and after installing heat pumps our power bill dropped by about 18%. That includes all electricity, not just heating, so the gain in heating efficiency was very considerable.
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The Guardian is a UK publication.
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Generally, cold climate heat pumps are an efficient source of heat down to -15 degrees Fahrenheit
“Generally” is the wrong way to approach this. What you should be looking at is the specific capabilities of the actual system that you are considering installing. Some of them can go much colder.
If the Mitsubishi FE18 isn’t efficient in your climate… then don’t buy that unit. Simple.
If it’s really cold where you are… then you could consider a ground source heat pump instead one that uses air as a heat source. The ground doesn’t get anywhere near cold to have efficiency issues no matter where you are in the world and ground source heat pumps don’t cost all that much… though they do require a bit of digging.
Also, if your heat pump is inefficient for a couple really cold weeks a year… oh well. You’re still coming out ahead because it’s very efficient the other 50 weeks a year. It’s not like they stop working at extremely cold temperatures, they just produce a bit less heat than you might like for the amount of power consumed. Maybe they’re “only” 80% efficient instead of 600% efficient… you know what else is 80% efficient? Heating with gas.
it cannot be the only source of heat in a lot of cold climates.
I live in Finland. Heat pump is the only source of heat in my house.
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Some of the stations in Antarctica use heat pumps. They have been proven to work effectively at -53°C (-64°F) and do so reliably.
Are they more efficient at more reasonable temperatures? Yes. But they still work even when it’s very cold outside.
How well a heat pump works in cold temperatures obviously depends what temperatures it was designed to operate at. Don’t waste your money on a model that is designed to operate in a different climate. In fact a lot of heat pumps aren’t even capable of heating at all - they can only output cold air (which they can do even if it’s stinking hot outside by the way).
It can go down to -30C (-22f) sometimes or even below that
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Yeah averages are way higher than that. My point just was that saying they don’t work in cold climates isn’t quite true. Yes, there are locations with way colder climates than this but if Finland isn’t considered a “cold climate” then I don’t know what is.
Heat pumps are super common here. Many houses just have a electric resistance heating so people switch to heat pumps to save on electricity.
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Are you intimately familiar with the inner workings of your heatpump? Nearly all heatpumps in a cold climate have backup heat built in and it would automatically switch to backup when it gets too cold outside. -30C is well into the too cold category for it to function as a heatpump alone
Which makes the argument that heat pumps don’t work in the cold completely wrong from a user perspective.
Yeah I have no idea. The alternative would be electric radiators anyways so in most cases that wouldn’t make a difference anyways. Temperatures that low are quite rare - maybe just a handful of nights a year. Generally it stays around -10C
What happens when the power goes out
how often do you think the power goes out in finland
How often does it got out in Germany At least Finland built a Nuclear reactor to power most of the country unlike Germany which shut all their’s down
afaik power never really goes out in western europe unless something happens to the infrastructure (e.g. lightning strike or tree falling on a power line), what instead happens when we run out of generation capacity is that prices skyrocket.
In my house? Pretty much never. We have solar as well as a grid connection and can connect a generator as well.
In fact, I even have a second stand alone portable solar system that we take camping. It’s not powerful enough to heat a house… but it is powerful enough for pretty much everything else. And I can heat my house with a fire if it came to that.
Redundancy is the name of the game if you’re worried about reliability.
Well it obviously stops working and unless you have some other means of heating your house you’re kinda fucked and can only hope it comes back on soon as it generally does.
So? It is basically always as efficient as resistive heating at its worst, and the vast majority of the time it is massively more efficient. And even then they can remain more efficient even as low as -25C and might need resistive heating backup at places that get below that. But even in places that can dip below that they are often not that cold all year round. So overall throughout the year they are way more efficient on the majority of days even if you need a less efficient backup system.
We really need to think of the whole situation rather than just focus on the but sometimes part of the problem. Yes, sometimes they dont work as well. But overall through a year for the vast majority of places a heat pump can be all you need and is a lot more efficient than other heating systems.
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And what point does that happen? According to the article and other sources say similar things:
Even at temperatures approaching -30C, heat pumps outperform oil and gas heating systems, according to the research from Oxford University and the Regulatory Assistance Project thinktank.
And the lowest recorded temperature in the UK since 1961 is -27.2 °C. So the times you need to fall back to resistive or other backup systems is 0% of the time. And what do you count as a cold climate? is 0C cold? or -10C? -20C? I know many people that would say yes at any other those and I bet there are others that live in places that go way lower. Yeah, what you said is technically true, but without these numbers is almost a meaningless statement. In the UK, and most of europe this article is basically saying that heat pumps are more effective than other sources of heat even at colder temperatures and it takes extremes before they require alternative heating methods.
The way you worded your post it makes it sounds like on a average coldish winters day heat pumps become useless and there is little point in having them. Even if that is not what you intended.
I mean, in the colder climates that have natural gas piped to homes anyway.
Why not use a pilot light worth of gas to keep the evap side a tad bit warmer on the days that it drops real cold.
Sure, your still using some gas, but you’ll be extreme sipping at it.
I’d rather go full electric and get rid of the gas infrastructure entirely tbh. Take that cost and put it towards local power generation+storage.
Heat pumps most of the time and radiant electric heat for the few times the heat pump won’t quite cut it. Geothermal if that’s an option in your location.
Counterpoint: electrifying homes is also a huge cost savings in general once you are at the point where you’re willing to forgo that big gas furnace in favor of an efficient heat pump system.
Cookers use very little gas. It’s really only water heaters and furnaces that use a lot of it, and heat pump units are incredibly efficient for both those tasks. Though I will admit that the noise a heat pump water heater makes is just atrocious and you’ll need to figure out if your can manage that in your life (e.g., by setting it to only run at night, when you’re out of the house, or putting it somewhere far away from where you spend time).
Keeping a gas hookup at $15+/month for a single appliance like a water heater or range is an expense a lot of people can and should trim, but instead they treat it like a sunk cost and think “well I have this one appliance, so I may as well get MORE gas appliances”. Which is intended. The whole “now you’re cooking with gas” campaign and all the nonsense ad campaigns about how gas ranges cook better than electric* was a deliberate (astroturf) marketing campaign from natural gas utilities because they knew that keeping electric cookers in the house would stop people from abandoning the appliances that ACTUALLY use gas but were hard to get people passionate about. This isn’t a conspiracy theory; we have the memos and POs.
* the difference is at best unnoticeable to the average cook and I truly believe the performance is worse, especially when factoring in time spent cleaning. Electric ovens are flatly better and modern electric cook tops work super well, even if not induction.
It’s not an argument I’ve seen in this conversation yet, but I’ll also head this off: gas ranges are not the best cooktop for ultimate temperature control either. If you cook sugar or temper chocolate a lot, a standalone induction cooktop like the Breville Control Freak will do a way better job, and you don’t need to change your permanent kitchen appliances to make that work. Combine that with an induction kettle like others have mentioned, and the broiler for peppers (I do this weekly having moved somewhere that doesn’t have gas) and there is literally no reason to choose gas in the kitchen.
a standalone induction cooktop like the Breville Control Freak will do a way better job,
at $1,499.95 for a single burner it better damn well.
It’s for sure a professional tool, but nobody else really needs those features anyway.
Gas is great if you need to boil a pot of water right now. Like in a restaurant kitchen.
Any application that is not in a massive rush is just fine on electric.
Even modern radiant electric boils water faster (pretty typical for even a pretty low-end electric top to have a 3500-5000W quick boil burner). And induction or a kettle both do it a near order of magnitude faster. Not to mention none of them hugely heat up the room or require a superpower ventilator that sucks out your conditioned air. If boiling water fast is the task you care about, gas is almost certainly the worst choice. At least for home use.
Commercial kitchens are a different story that isn’t even part of the discussion. Even with three-phase power, to run an all-electric mid size-large commercial kitchen would likely require some crazy service level that wouldn’t be available in many places. It’ll be a while before that is an option.
I’ve found induction cooktops do just as well as gas at boiling water. The frustrating thing about them right now is the market is immature, so the good ones cost well over $1000 per burner and the cheap ones are so much worse (lousy coil sizes and poor heating precision) they aren’t worth using as anything more than a camping stove for tiny little pans where you don’t need precision. It’s like nobody in the industry wants to make these things good enough to actually replace the old technology, they just want to price gouge for all it’s worth while it’s still seen as the “expensive, hard to make, premium option”.
Very good induction cooktops are nowhere near $1,000 per hob and can boil water in a fraction the time as gas. Don’t buy the Frigidaire crapola and the stating price for a very good full induction convection range with 4-5 hobs is ~$1,250. Spend twice that and you’ll have a machine with no downsides.
Technology Connections on YT did a side-channel experiment on this very thing.
Normally I wholeheartedly recommend his stuff, but the side-channel content gets very long winded and rambling, linked video included.
Induction is much, much faster.
I haven’t seen this argument listed yet, but my reason for wanting to go off natural gas is how much we lose in transmission. I don’t feel like finding sources right at this moment but most estimates I’ve seen are ~2%, and methane is a pretty potent greenhouse gas.
Methane is one of the cleanest burning fuels there is. There should be more effort put into fixing the distribution leaks rather than trying to switch everything to electric.
Fossil methane is still fossil. Ie. not part of the CO2 cycle, and thus contributing to the greenhouse effect. Methane itself is 20 times more potent, and we should do everything we can to limit methane emissions, both fossil and natural.
Agriculture is a big source of natural methane emissions, and even fairly small dietary changes can significantly reduce livestock emissions, but don’t see anyone doing that either.
Highly suspect small gas line leaks won’t be fixed either.
That is a rather big ask and maybe that effort would be better directed elsewhere.
Also, think of it this way. Isn’t it a bit crazy we send lines of pressurized, explosive gas directly to most homes in North America? If we do need to keep burning natural gas, we can do that in power plants and get about the same, if not better efficiency by using this electrical generation with heat pumps.
That’s a fair argument. Even if every used a tiny bit, there would still be a lot of loss to the atmosphere through leaks/etc of the distribution system.
So yes 100% elimination would be ideal.
But this could be a viable middle step between 100% gas heating -> Supplemental/Heat Pump -> 100% Heat Pump
You’re better off heating the inside of the house with gas that heating the outside of the house with gas and using the heat pump to transfer that heat into the house. Replacing the gas line with lines for the heat pump would be best.
It’s literally pulling heat out of thin air (or ground).
As long as you can keep the evaporator above the evaporation temperature of your compressed refrigerant, you’re golden.
Also keeping the evaporator from getting covered in ice where it doesn’t work. Yeah you can defrost but in certain weather it’s just going to ice up immediately.
Bless you. I love that guy. So gosh darn nit-picky on the details and its the best!! Never thought hour long videos on heat pumps or refrigerators or car headlights would hold my attention or be a favorite part of my week but he makes it happen.
His Christmas light videos are a highlight of the season every year!
No shit
The study isn’t wrong, but it’s also not right, IMO.
This doesn’t seem to mention the cost of the energy, just how “efficient” it is… which, honestly, “efficient” can imply several things, and they don’t seem to clarify what (at least from my first pass of this doc).
The issue is that even if you’re getting 3-4 times as much heating/cooling as you could with something else, per jule of energy potential that is put into the system (in whatever form that is), if your energy cost for that source of power is high, it’s going to lose the financial argument every time.
Sure, a natural gas furnace will consume “more fuel” and produce less effective heat than a heat pump, but if you’re paying 10x the cost for electricity, then you’re still going to end up spending more per degree of heating than with the cheaper fuel.
Where I am, electricity is pretty cheap, but natural gas is tremendously cheaper per jule… so we can actually pay less by using the “inefficient” fuel for our home.
I don’t think the numbers are dramatically different at the end of the day, but this study seems to completely ignore the core issue that most people will be concerned with… which is: “will this save me money?” Which is arguably the more important metric.
honestly, “efficient” can imply several things, and they don’t seem to clarify what (at least from my first pass of this doc).
How would you like to define it?
How about this for an analogy - which of these two is more efficient:
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Plant some wheat in your back yard, buy fertilised eggs to hatch into chickens, plant tomatoes and basil, plant an olive to grow a tree, and eventually, years down the track, you can make yourself a bowl of pasta.
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Notice your next door neighbour already cooked some pasta and made more than they can eat. Ask politely and they’ll just give you a serving.
Obviously - the second option is more efficient, and that’s effectively what a heat pump does. They don’t heat up your home, they just take a bit of heat from the air outside and move (pump) it into your home. It’s far far more efficient than creating new heat from scratch with a gas system.
Exactly how much more efficient will depend on the outdoor and indoor air temperature, and on the brand/model of heat pump you buy, and other factors (such as the length of the pipe between the outdoor unit and the indoor unit). You really should ask for specific advice on your home - but in general, a heat pump is extremely efficient.
Where I am, electricity is pretty cheap, but natural gas is tremendously cheaper per jule… so we can actually pay less by using the “inefficient” fuel for our home.
Have you actually looked into it, or are you just making assumptions?
I can tell you that my heat pump, in my house (yours will be different), in my climate, adds about $5 per week to my electricity bill. Is your gas bill less than $5 per week?
Or at least - that’s how much it cost before I had solar panels. Now that I have solar… it uses about 20% of the power typically produced by the solar panels on my roof leaving plenty of excess power that we sell to the grid for about the same amount of money as what we spend buying power overnight. Since we installed solar our entire electricity bill is about $0 (and we use power for a bunch of other stuff, including to cook breakfast and dinner when the sun typically isn’t shining*). We don’t have a large solar system either - in fact, installing solar cost less than installing heat pumps.
(* our solar system comes with instruments and software to measure our consumption - and I can tell you that heating up a family meal with an electric cooktop uses more electricity than heating an entire house with heat pump… because the cooktop is creating heat, and the heat pump is simply moving heat)
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What’s also interesting is that you have to factor in the costs and CO2 emissions of the fuel source and it’s delivery method. A new building code for a county in my area was adopted which requires calculations for energy efficient HVAC systems and also CO2 emissions with those systems. Surprisingly, natural gas has less CO2 emissions associated with it, while electricity is 2.86 times as much. This is because grid electricity is mostly produced by fossil fuels, then needs to be delivered to the site but there are many losses along the way. So even if the all electric equipment is twice as efficient as the equivalent natural gas equipment, it still contributes more CO2 production. This is part of the issue with phasing out natural gas and moving to all electric in its current state. But with that is the push (and requirements) to produce energy on site and shift towards net zero energy for commercial sites, which is definitely better than using grid power from an emissions standpoint.
Where I am, electricity is pretty cheap, but natural gas is tremendously cheaper per jule… so we can actually pay less by using the “inefficient” fuel for our home.
Most of the push towards rapid adoption of heat pumps is happening in Europe, where geopolitical developments (to put it mildly) caused gas prices to spike last winter. The nature of the natural gas logistics means that different continents can have wildly different prices (unlike petroleum, where you can always throw it on a ship and send it from where it’s cheap to where it’s expensive), so a lot of European countries are seeing these debates play out against the backdrop of their own energy markets. Germany passed a law this year that would phase out new gas furnace installations, so that’s why a lot of the debate is happening with a focus on German markets.
Whether (or how quickly) a transition to heat pumps pays for itself in euros will depend a lot on what happens in the future to gas and electricity prices.
A sticking point I encountered - the drop in efficiency as the weather gets colder means you need a unit sized to heat your home on the coldest days you expect to encounter. So you need to buy a heat pump that’s larger than you need for 98% of the year just so you don’t freeze that other 2%. In addition to higher cost an oversized unit is less efficient because it’s cycling more.
So this is where “heating strips” or “backup heating” come in, and then I get we’ve come full-circle.
I don’t see how this is “full circle”. In places where it does get that cold, most homes already have a form of heating for the house. Adding on a heat pump or, at least in my case in the Midwest, replacing the central AC unit with a heat pump just means that you’re only kicking that original heating system on a few days out of the year. That’s a massive reduction in use compared to being the only source of heat for half the year.
It’s a problem that new construction homes would need to fix if they don’t want an NG connection at all, but it’s not unsolvable.
I think modern inverter units are not less efficient when oversized. They are able to run at varying levels rather than cycling.
Those “heating strips” are only used a few weeks every year in my case.
Has not been updated for a while, but relevant link…
https://www.energy.gov/eere/buildings/residential-cold-climate-heat-pump-challenge
Now if electricity was just less than 3x the price of gas, we’d be winning.
would be a neat story in 1920
Unfortunately gas costs a lot less for the same amount of energy. So it’s only going to save you money if you use simple electric heating.
For those of us on gas boilers, the prospect of a system paying for itself (maybe) in 50 years time isn’t overly enticing.
In this context is a “heat pump” the same thing as an inverter air conditioner?
A split system.
That’s what most of Australia uses and looks like the pic but Ive never heard them called a heat pump.
Yeah, for some reason we renamed them to heat pump.
I suppose they can also be used to slowly heat water as well as the air, which is the main difference.
I like “heat pump”. It’s a very nice ELI5 name. It’s a pump for heat. A water pump takes water and forces it to where it wouldn’t go naturally. A heat pump does the same.
Follow the Money for who funds these studies
they do https://www.raponline.org/# feel free to investigate on them.
Electric fans are even more efficient, and about as effective.
What???
This is about heating homes in winter, what are you talking about?? Electric fans are more efficient at what?
If you turn the fan up high enough it will blow the heat from outside into the house. Trust me, I’m a scientists.
🤖 I’m a bot that provides automatic summaries for articles:
Click here to see the summary
Heat pump uptake is rising in many countries as fossil fuel energy prices have soared following the invasion of Ukraine and as governments seek to reach net zero greenhouse gas emissions.
France, for instance, installs 10 times as many heat pumps as the UK, where many people are unfamiliar with them and doubts about their efficacy have been widely publicised.
The authors said the findings showed that heat pumps were suitable for almost all homes in Europe, including the UK, and should provide policymakers with the impetus to bring in new measures to roll them out as rapidly as possible.
Dr Jan Rosenow, the director of European programmes at the Regulatory Assistance Project and co-author of the report, said: “There has been a campaign spreading false information about heat pumps [including casting doubt on whether they work in cold weather].
The Guardian and the investigative journalism organisation DeSmog recently revealed that lobbyists associated with the gas boiler sector had attempted to delay a key government measure to increase the uptake of heat pumps.
The UK government is consulting on proposals for incentives to households to take up heat pumps, which at about £7,000 or more can cost two or three times as much up front as gas boilers.
Saved 57% of original text.
But does it more effectively keep houses warm in cold weather, and cool in hot?
Heat pumps are most effective in moving heat from where it is abundant to where it isnt. This means they’re best at keeping your house warm in warm weather, and keeping it cool in cool weather.
Then a heat pump won’t do any good. Achieving the right temperature is far more important.
Yes. Heat pumps heat homes more effectively than the alternatives down to remarkably low temperatures, and many models also serve as air conditioning - it’s merely a matter of inverting the process.
So, what happens when high winds or a blizzard takes down the power lines
I lived through the 98’ Ice Storm in the Northeast US Didn’t have power for three weeks
I’ve got news for you.
Even if the gas lines work, your furnace still needs power to open the fuel lines, ignite the fuel, circulate the inside air through the heat exchanger, and, above all else, do it safely.
You’re screwed either way if you don’t have power.
Sure, you can run a gas fired furnace on batteries far easier and more cheaply than you could with an all electric system (regardless of how it’s generating the heat), but in every case, you need electricity to run the systems.
This is all dancing around the very real fact that we need to upgrade the grid. Between air conditioners, heat pumps, and electric cars, adding to the already increasing demand from so many computers and computerised gadgets that we have today, sucking back so many more kilowatt hours more power per day, per household than ever before. About the only thing that’s going to work when the power shuts off is your toilet.
Thats the rediculous thing. I constantly see people argue about power outages (which realistically aren’t even common in many countries). My parents had a power outage, and couldn’t use their Gas heaters. When I had one, I couldn’t use my instantaneous gas water heater (although, my heat pump based one, can keep water warm for 3 days apparently, so its actually better). My old gas heater actually apparently has been known to burn down houses when there is no power (because the fan stops, and apparently in some circumstance, they overheat)
People don’t realize how dependent many of their gas appliances are on power
People don’t realize how dependent they are on power in general. It runs basically everything, with the exception of your car.
Yet, nearly nobody has any plans for what they’re going to do if the power stops working.
Most households, almost everything is electric or electrically assisted… the only real exceptions I can think of, are your vehicle, barbeque, and water systems (not including hot water). So toilets flush, you can cook on the BBQ, and you can drive away from the collection of wood and bricks you call a home, and go somewhere with electricity… that’s about it.
Battery, generator, or some systems work off the fuel pressure
Batteries or generators could also work for heat pumps, or you could have emergency backup propane heat. Basically the short answer to your concern is “prepare” just like how you handle every other emergency situation like that ever, regardless of what kind of heating system you use.
Also a big part of it is fixing up your insulation. Modern insulation is great, a well insulated house is super cheap/easy to heat.
A heat pump and propane heat seem like a huge waste of money for duplications Plus where do I get the propane after it’s banned
No - a gas electricity generator, powering a heat pump, will use an order of magnitude less gas than if you used the gas directly to heat your home. That’s how efficient heat pumps are.
Home generators are not very efficient, they lose a lot of energy to heat and noise. It’s close to the break even point so depending on your generator and heatpump, you could use more gas than with a modern gas furnace. Even with a theoretical perfect 100% efficient generator, it’s not going to be an order of magnitude less gas because heat pumps are not 1000% more efficient than a gas furnace
Switching to propane is one safer alternative that is being recommended for people with natural gas lines to their houses, it is less leaky and cleaner burning than the methane stuff. Propane won’t be banned, but it will become more expensive as supplies dwindle.
If you have an air conditioner you already have a heat pump, it just needs to be one that can alternate directions between heating and cooling. Also, backup emergency heat would not need to be nearly as extensive as a full house propane furnace. Or, you could just use a propane emergency generator instead and keep using the heat pump. Propane can be stored long term much more easily than alternatives like gasoline, and while it can be pricier, just having enough for emergencies is not a great cost.
