Heat pumps twice as efficient as fossil fuel systems in cold weather, study finds
Heat pumps twice as efficient as fossil fuel systems in cold weather, study finds
Apparently it doesn’t work in Germany. Physics work differently here. At least that’s what our corrupt politicians want us to think
I hear that too. Not just politicians, there's loads of experts lecturing on heating technologies. It's just too cold in Germany for heat pumps. Doesn't stop Scandinavia from getting them, granted, but in Germany it's just too cold. No point. Sorry.
I can't get an electrician and contractor to come install one (as an AC mainly) inside of 6 months, and I've been trying to find one for 6 months.
The heat is actually killing me I can't sleep and have other health problems. I brought a dual hose unit from the US with me I'm running on a voltage converter and it's the only thing keeping my apartment livable.
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.
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.
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.
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.
Most modern heat pump systems account for that and have electric heating/defrosting built-in for those few cold days a year.
Also it's not like you have to remove your old heating system*; you can just plumb in the heat pump into your central heating and have cut off valves for the original system, so you can still use it as a backup.
*) unless your government is retarded and in order to get subsidies they require you to uninstall it
Quite frankly, in really really cold places (the only places where your criticism applies) you should not have a single source of heat period. You always need a backup in case one of your heat sources fails. It does not have to be able to heat your house a lot, just keep it stable above freezing, but you do need a backup.
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.
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.
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.
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.
It's literally pulling heat out of thin air (or ground).
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!
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:
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)
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.
if your energy cost for that source of power is high, it’s going to lose the financial argument every time.
How high, is the question. How much more is electricity where you live that heat pumps "lose the financial argument every time"? Where I'm from a kWh of electricity is roughly 2.8-3x that of natural gas, so most modern heat pumps will beat that, some by quite a margin.
If globalpetrolprices.com is to be trusted and Canadian natural gas is 0.063 CAD and electricity is 0.165 CAD you're very much in the same boat with a 2.6 ratio. Most heat pumps should be able to beat a 2.6 SCOP even in Canada.
So, sure, the study only looks at COPs and not at overall cost, but I think it's not unreasonable to expect home owners to be able to divide electricity price by gas price and compare it to the SCOP of heat pumps on offer.
Finally someone taking sense.
Asking me to compare my own bills between natural gas and heat pump is insanity, I don't have both systems installed just for shits and giggles.... but it doesn't seem to stop people from saying I should do that sort of insane thing to really know.
That site sure is interesting, I haven't dived into the data enough to know how they got the figures they did, or what it represents... but assuming they're saying that it's saying that $0.63 worth of natural gas gives you the equivalent thermal output of 1kWh of conventional electric heating (more or less)... which I think it kind of does, since, to the best of my knowledge, electric heating systems are among the most efficient at converting 100% of the energy input to heat output (or as close as we can get to that). As we know heat pumps exceed this because they're not generating heat, they're just moving it around.
Also, a blanket statement like "heat pumps should be able to beat 2.6 SCOP, even in Canada" is problematic, since Canada is huge, and some of that landmass is in the Arctic circle. To be fair, 90% of Canada's population (or something similar to that) is in the southern 10% of the landmass.... still. If we're being detailed, then such blanket statements should be avoided. A good alternative is "for the majority of the population of Canada", which is wholly accurate.
There's also other inefficiencies that aren't being considered and unless we get really deep with the information, that fact is unlikely to change; however, those inefficiencies may make heat pumps even better on paper....
There's a lot to say about this incredibly complex topic. And that's not even touching on the nuances of the word "efficiency".... since efficiency relies on specific conditions, and usually is a comparative figure. Eg, the Ford F-350 super duty is an extremely efficient vehicle, when compared to the Ford model T.... many decades of innovation will pretty much guarantee that statement is accurate. But comparing the F-350 to, say, a Toyota Prius on MPG alone, then the F-350 seems like a gas guzzling bohemouth, that's a symbol of gluttony.... Wasting so much more fuel, to travel the same distance. Both saying that the 350 is incredibly efficient and also that it's extremely inefficient, these are both true, depending on context.
There's too much nuance here that I'm just going to stop talking before I ramble myself into getting cancelled somehow.
It also doesn't add up if you're getting twice the heating per joule of input if you can only input a quarter the number of joules as your source is limited.
No shit
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.
You'd usually run two or more units in a cascade/multiplex when requiring large amounts of power rather than having one giant unit. Means you can turn off one or more units entirely for low heating demand.
Also choosing a unit (or units) that use a speed controlled compressor will limit cycling as they can ramp for the actual load.
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.
The optimal solution is to add a small heatpump in addition to a gas heating
The only downside (in comparison to fuel burners) is complexity. Heat pump systems are extremely complex with a lot of parts that could get fucked up over time.
A gas furnace is as simple as it gets with almost no moving parts. Coal/wood furnaces are a bit more complicated if you don't want to blow 100% of the emissions into the air... you need good well maintained filter systems. But it's still far less complex than a heat pump.
So I understand the appeal of furnaces. Simpler systems are easier to understand, are harder to break and easier to repair/maintain.
I think that problem is tackled too rarely in these articles. If you can't take away the fear that people will have a higher upfront invest and higher maintenance costs and higher failure risk, that makes it too convenient to cling to what they know and understand.
Edit: oven --> furnace
Eh, I think you might think heat pumps are more complicated than they are. I think they're about as complicated as a furnace. At the end of the day, in both your just pumping a gas from one place to another, changing the state of the gas, and then running that past air to heat or cool it.
It depends. The most basic implementation of a heat pump is basically an AC system with a reversal valve.
To be fair to the previous commenter, the air conditioning system of an air handler (aka furnace), is usually one of the more complicated parts of the system.
The issue is that even air conditioning systems are getting rather complex, with multi-speed or continuously variable speed systems... which add significant complexity.... meanwhile adding a reversal valve to a continuously variable system easily makes it far more complex than any other system that's integrated into the air handler.
I'll also note that heat pumps come in many different shapes and sizes, some are mini split systems, others are geothermal bohemouths, and some are air-exchange systems to be integrated into an air handler (aka furnace). The most efficient heat pumps are usually the geothermal kind, which are pretty easily the most complex; air exchange heat pumps are basically just AC systems with a reversal valve.... they all have their challenges though...
It's just, a much deeper topic than saying that it's strictly more, less, or the same level of complexity as something else, since from the start, the term "heat pump" represents an entire class of diverse devices... the same can be said about a furnace or just about any heating system... some are extremely simple while others make my HVAC guy cry out for someone to make it make sense. YMMV.
Heat pumps dont replace gas ovens. They replace central heating systems. They are not that much more complex then a central heating system and come with a lot fewer safety concerns. And heat pumps are not new technology - they are just AC units that can run in reverse to heat instead of cool. We already know how well they work and how often they fail and a lot of the world is already reliant on them just as much as others are reliant on gas central heating.
Now if electricity was just less than 3x the price of gas, we'd be winning.
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.
A split system AC is a heat pump in any context. So is a refrigerator. They're all the same technology that move energy via a refrigerant's latent heat by compressing it into a warm part and letting it expand into a cold part.
Cool, thanks. In that case it's about one month until I can't live without my heat pumps. They stop my balls from sticking to my leg.
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.
For larger homes with central heating and radiators inverter air conditioners aren't really a great solution - they are expensive (especially when you don't have/need an air conditioner in the first place), unsightly and work for more or less just one room. A heat pump is a generic term for a multitude of things, but as a replacement for central heating you'd most likely have just one outdoor unit that spews cold air and inside you'd have a large heat exchanger where you warm up the water for your central heating (and possibly warm water in general for showering and the like).
It's pretty amazing.
Has not been updated for a while, but relevant link…
https://www.energy.gov/eere/buildings/residential-cold-climate-heat-pump-challenge
would be a neat story in 1920
In Germany this will likely still be a controversial take in 2026. Our political right managed to shift this debate into ideology territory and a good chunk of people believe heat pumps are environmentalists' fever dreams that don't really work in cold Germany.
It's still news today because every time heat pumps are mentioned someone will say that 'they are nice but it's too cold to use them where I live'.
That's like the stupidest take, especially for most of Germany. In the worst case you'd supplement the heat pump with electric heat so in the coldest days when it doesn't work at all (which will be a few days a year at most) you'd get to ... checks notes ... 1x efficiency, which is only as bad as having regular electric heating which many people have anyway.
Follow the Money for who funds these studies
they do https://www.raponline.org/# feel free to investigate on them.
Sadly, makes bugger all difference here in Australia - our electricity is mostly coal-generated.
At this time, we're up to over 36% renewable.. So we are getting better. In 2017, it was only 17%. If we got rid of the libs earlier (who made the carbon tax debate toxic), we'd be so much better. Even with coal generation though, Heat pumps are still more efficient, as they're measured well over 100% efficient (200%+), whereas gas is less than 100%
It's still usually more efficient and better for emissions when the coal is burned at a power plant with high efficiency and filtering systems.
Yeah, you're probably right. Just grumpy that we still burn fucking coal for our power here, and we have so much wide open space we could be using for solar generation.
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.
But does it more effectively keep houses warm in cold weather, and cool in hot?
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.
🤖 I'm a bot that provides automatic summaries for articles: ::: spoiler 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. :::
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
Battery, generator, or some systems work off the fuel pressure
Tbf most modern fossile fuel heating systems require power as well to some degree.
I think going forward we will have a much more decentralised power grid, as in people will have batteries to store a significant amount of power which they produce via solar panels on top of their houses. Also many electric cars today can be used as power storage.