I've been keeping an eye on heat pump water heaters for awhile, but right now they mostly make sense in warm climates. The big problem is they're still specialty products and marked up like crazy, but also they tend to use cheap components which makes them loud and prone to failure. If you run A/C for the majority of the year then they pay themselves back reasonably quick, barring early failure, but in colder climates they make your house work that much harder to keep the space warm.
The most optimistic hope is that the government mandate will force enough demand that manufacturers can enjoy some economies of scale and actually try to compete on price. I don't think this will happen anytime soon.
Ask This Old House had an episode literally yesterday where they installed a \ solar-assisted split heat pump water heater. There is a component that goes on the outside of the house but not on the roof which simplifies installation.
https://www.youtube.com/watch?v=uqyAWkXXt3A
https://www.neshw.com/residential/solar-heat-pump-water-heat...
I had a heat pump installed in 2010. In a cold climate. Only used for heating. It paid for itself extremely quickly - less than three years. It's still going strong, in 2026. It's important to maintain it regularly, i.e. deep cleaning every two years or so. The first time I got a company to do it for me, and the technician taught me how to do it all by myself, so that's what I do. In any case having a professional doing it wasn't expensive either. And I clean the dust filters (very easy) every second week or so.
Installed mini-splits to replace the propane stove that heated my house, DIY job, so all it cost was the units themselves and some materials.
Propane bill (no natural gas, town of 500) from Oct 24 to Feb 25 (installed the mini splits that month) was $1200, for just heating.
My mini-splits are on a dedicated sub panel with an Emporia Vue 3 energy monitor. $604 in electricity consumption, and that includes air conditioning over the summer months.
For what it’s worth, our winter weather averages 25-35F with the occasional few days dipping to tens, single digits, and the occasional -10 freak; but these units just BARELY have a HSPF4 rating to classify as “cold climate” models. Still going to pay for themselves in 6 years without any tax credits, and 4 or so since I still installed them when they were available.
What did you heat with before?
Electric resistive heating, which is the main power source here (all hydro, until recently). Plus a wood stove in case of power cuts. We used that one quite a bit during cold spells before the heatpump came along. Now not much at all.
Certainly not gas or oil, which are still cheaper to heat with than heat pumps.
Modern heat pumps are cheaper than oil for heating just about everywhere. They're cheaper than natural gas in most places, unless electricity prices where you live are particularly high.
Yes, and many places have high electricity costs. And btw, those are hard to foresee, so if you make a long term investment into a heat pump that is supposed to last 20-25 years, you have no idea how electricity prices will affect you. That's obviously true for gas and oil as well. I do concede that my original point was too blanket-y.
I have a heat pump btw., with COP 4.5 (below ground). Costs me EUR 2.5 - 3k per year to heat the house.
in CA my natural gas is far cheaper than the heat pump sadly
In western europe today, I spend €10+ per day to heat my home (17 degrees mind you) with a gas powered boiler for radiators. I can run my mini-split on 18 degrees all day for a couple of euros. I moved here from the US in 2022 right after the full scale invasion of Ukraine so natural gas prices skyrocketed overnight.
I don't really understand what the aversion is to forced air climate control here other than "it's not as comfortable" which from what I've gleaned from other people is taken to mean noise/moving air/humidity. Coming from the southern US, I find all of those points to be a non-issue for me. I've slept with a fan on my entire life, so if I can shave off 50% of my heating costs for a few decibels of fan noise, sign me up!
I don't buy your numbers. I'm in Western Europe myself, and have run those numbers multiple times. Kilowatt for kilowatt (COP adjusted) gas is always cheaper than a heat pump.
Hm? Around here oil was never been in the same (low) order of magnitude. Those who installed oil heaters many decades ago regretted it quickly. And it's been illegal to use them for a couple of decades as well now. Gas has never been an option in my region, there's no infrastructure for that. We have used gas in Japan until now, but even that we'll be phasing out (I live in two places)
> Those who installed oil heaters many decades ago regretted it quickly.
That really depends on the oil heater, no? You can't compare a heater from the 70s with a modern one. That's like saying I don't drive modern cars because cars in the 70s were unsafe and stank.
Needing an oil tank, smell, expensive (oil price typically increased drastically compared to the beginning), pollution, and, as I said, made illegal in cities for various reasons, pollution and expenses related to dig up and get rid of the oil thank, and more.
I’m in Japan too. Could you name the model you ended up going with? My heating bill in the winter is insane.
The model is not yet decided, we're in the finalizing stage with the building company. What we have been focusing on is a well insulated house, unlike the old one which has no insulation at all.. if we tried to heat that it would not only be extremely expensive, it's impossible to even heat the small bathroom with an electric heater. So instead you kind of get used to it. Took me a year to stop feeling like I was freezing, at 4C in the bathroom on February mornings. We have been using a gas heater (plug in the floor) in certain places on the ground floor, but we limited that as well. So, with an insulated, small house, we believe we will be able to keep the costs down, using heat pumps and heat exchangers, plus solar and battery (using the car battery).
Oil heating has usually been the most expensive way to heat in the UK, on par with resistive-electric.
That's completely wrong.
Electricity (standard): 33.34 p/kWh
Heating oil (gas oil): 10.54 p/kWh
Kerosene: 6.20 p/kWh
Mains gas: 7.68 p/kWh
https://www.nottenergy.com/advice-and-tools/project-energy-c...
I think a heat pump only for water isn't the right way to go. In the EU, new systems I see use a single heat pump for all heating and cooling in the house including heating water.
I do miss my natural gas on-demand water heater from when I lived in the states though. Unlimited hot water was nice, and it took up almost zero space.
> I do miss my natural gas on-demand water heater from when I lived in the states though.
Isn't that what we call a combi boiler in the UK (and Europe?) I've recently moved from having a big hot water cylinder to a combi. The space saving is nice, but there are downsides.
Waiting for the hot water to come through is annoying and I'm often just wasting cold water waiting for it to come through hot. There is a "pre-heat" feature which would be nice, but then it would keep it warm 24 hours a day which is ridiculous. Maybe some better boilers can time the pre-heat. That would probably be close to perfect.
The other downside is it can only really supply one tap with hot water. So if someone is having a shower and someone else runs a hot tap it can be unpleasant. Requires some coordination between householders.
All in all I would definitely prefer a cylinder if I could afford the space it takes. Modern cylinders are incredibly efficient. I once turned the heating off for a week while away on holiday and when I came back the water from the cylinder was still tepid.
The natural gas powered Rinnai I had could supply 2 showers and a sink with hot water at the same time just fine. It did take a little longer for hot water to come out the tap beyond the usual flushing the cold water out, though it was not a significant amount of time.
> There is a "pre-heat" feature which would be nice, but then it would keep it warm 24 hours a day which is ridiculous. Maybe some better boilers can time the pre-heat.
Yeah one of my colleagues has a preheat which can be triggered manually and via automation. They also have a preheat loop which cycles hot water through the entire piping as the boiler is on an edge, so it takes ages for hot water to reach the far bathroom.
While they are not as efficient or flexible, they are many times more efficient than resistive electric water heaters. I've installed one with in house air intake (due to construction reasons) in my house and it cooled down the basement by a few degrees (and removed air moisture as an added bonus). In summer the thermal capacity of the ground heats up the basement again, in winter it's a bit cooler, but it still works efficiently.
They are efficiënt but all that efficiency is eaten up by electricity being more expensive than gas.
Which models are you looking at? I was still quoted separate pumps for floor heating and a boiler with the pump built in taking the energy from the air two years ago.
Is it something from nefit by any chance?
This is promising.
https://www.pv-magazine.com/2026/01/29/samsung-releases-new-...
> The South Korean giant [Samsung] said its new EHS All-in-One provides air heating and cooling, floor heating, and hot water from a single outdoor unit. It can supply hot water up to 65 C in below-zero weather.
> Dubbed EHS All-in-One, the system provides air heating and cooling, floor heating, and hot water from a single outdoor unit. It is initially released for the European market, with a Korean rollout expected within a year. “It delivers stable performance across diverse weather conditions. It can supply hot water up to 65 C even in below-zero weather and is designed to operate heating even in severe cold down to -25 C,” the company said in a statement. “The system also uses the R32 refrigerant, which has a substantially lower impact on global warming compared with the older R410A refrigerant.”
Afaik heat-pumps in the EU can provide unlimited hot water–what am I missing?
Geothermal (and airbased) pumps theoretically do not have unlimited heating capacity. For example my pump (Daikin Altherma Geo 3) has a 180 litre water tank so it can ”only” supply 180 litres hot water at 65 degrees Celsius and takes about a minute to heat two additional lites.
So if I want to quickly scald myself in a 400 litre pool at fifty degrees I can’t. But if I had a gas heater that would be possible!
Depends on how you measure unlimited. My hot water heater can pretty much indefinitely supply hot water for a single shower head with a modern water saving design. It can heat faster than 1.2 gallons/minute
You're about 20 years behind.
My heat pump is working great at 0F. It's 7 years old.
It really depends on how well your home is insulated. Heat pumps don’t work well on old, poorly insulated houses in cold climates. If they can keep up, which is a big if, the price of electricity generally dwarfs natural gas, even if the heat pump is running at 250-300% efficiency.
> Heat pumps don’t work well on old, poorly insulated houses in cold climates. If they can keep up, which is a big if, the price of electricity generally dwarfs natural gas, even if the heat pump is running at 250-300% efficiency.
I've got a 1930s semi-detached house (UK, north of England) - heated solely by a ASHP for both heating and hot water.
Our Seasonal Coefficient of Performance is currently 3.47 (347% efficient) - even if limit that to just last month (coldest month of the winter so far in the UK) our COP was 3.25 (325% efficiency).
Roughly speaking if you can achieve a COP over 3.2x in the UK it should be roughly on a par with gas, assuming you go 'gas free' (i.e. you can make the saving on the gas standing charge).
Personally we're running at ~£200 annual saving vs. my estimate of what costs would be for equivalent gas boiler - that's thanks in part to being able to do all our hot-water heating at night rates.
House wise - we don't have cavity wall insulation, have 15+ year old double-glazing and probably should have more insulation in the loft (it fills the rafters but I think these days that's considered not enough).
Also with changes to ECO (energy company obligations) and RO (renewables obligations) the differential between gas and electric will reduce further
Anyhoo - added my example to show that ASHP can work perfectly fine in old, poorly insulated homes in (moderately) cold climates.
ECO/RO link - https://www.moneysavingexpert.com/news/2025/11/energy-bill-c...
The issue with poorly insulated houses in cold climates is not about efficiency. The issue is that the thaw cycle makes it impossible to actually come up to temp because too much heat is lost during thawing. Most of the UK isn’t really considered “cold”, which is probably why you don’t have this issue.
Yeah the UK isn't really very 'cold', but figured would include my example to show that not a problem in UK-equivalent of cold climates.
From a quick skim around it appears ASHPs can continue to work at -20c even -30c IF they are units that were designed for cold climate operation, albeit they can't secure the same SCOP/efficiency as they can with warmer temps.
It also looks like homes in these colder areas will often install the ASHP + have some form of additional heating as a back-up (e.g. electric heating) to compensate for the limitations of the ASHP in the coldest weather.
It's not really correct to say that heat pumps don't work well on old, poorly insulated houses in cold climates. That it's a heat pump is not the issue, that it's cold is not the issue, the problem is only that with poor or no insulation in a cold climate you'll need a huge heater (say, 10-15kW just for the living room). And domestic heat pumps are not designed for that range. If you could get one that big then it would work very well indeed.
If you have a poorly insulated house then the fix is to insulate it, which is what a lot of people are doing around here, with very hold houses. My house is less than 60 years old and very well insulated for the time, and it holds up even today - it's always warm, with the heat pump not even close to its max power.
The issue with “just” insulating your home is that many homes weren’t designed with insulation in mind and thus it’s not a straightforward proposition.
For instance, masonry was a common building material and that is not easy to insulate. You need to add many inches of insulation on either the outside or the inside, both of which have complications.
Even in a basic stick framed house, you’re still talking about taking down all the exterior walls, likely involving removing plaster and replacing it with drywall. Plaster has a number of nice properties, so it’s sad to remove. And that’s not to mention the price of this work.
Finally, roofs need special consideration. Most roofs today need to be properly vented, which was not as much of a consideration when the houses naturally breathed. Venting today is often done with soffit vents. Yet on historic houses, soffits are typically one of the nicer details. It’s not trivial or cheap to install venting in such cases.
> If you have a poorly insulated house then the fix is to insulate it
I've been quoted prices to insulate my house that represent 50% of the original acquisition price of the house.
I would need to pay 0€ for both electricity and heating for the next 100 years for this to make sense at current prices.
To clarify my parent post: My house is also 7 (now 8) years old and has 6 inch (15cm) walls with air-tight walls. We built with solar, which got the cost of electricity down to an estimated 4-5 cents per kilowatt hour.
At that price, resistive heating cost about as much as what I paid for gas at my old house.
I went with a heat pump to hedge the bet. (I was also pointed away from geothermal.)
If the insulation wasn't as good, or electricity more expensive, I would have used a different heat source. I was looking at pellet furnaces at the time, but never seriously got into the research before the solar proposal came in.
Mine are in climate zone 6. They're only a couple years old. The coldest temperatures I've run them at so far are -21°F and they kept the house adequately unfrozen. They'll maintain a COP of 2 down to 5°F IIRC. The hot water heater is an 80gal Rheem heat pump unit. No complaints there either. It would be pretty great to have some thermal storage though, temperatures in the dead of winter here are usually above 5°F during the day but drop well below zero at night. Blasting the heat pumps during the day to bank heat for overnight would be far more efficient.
heat pump for house !== heat pump for hot water
I don't know what it's like where you're living but here in Switzerland it's completely normal to have one heat pump that does both. Here there's a lot of floor heating, which also uses water, so you usually just run one loop to the "boiler" (a water tank with a copper loop for the water from the heat pump to circulate through) and one through the floor and have a valve to switch which is running through the heat pump.
I have one of these: https://cta.ch/en/private/products/ah-i-eco-innen
I got it in October so most of the time I've had it has been <10C. It's produced 806.3 kWh of heating for hot water and 6587.2 kWh for the floor heating. It consumed 302.7 kWh and 1801.4 kWh respectively, for a COP of 2.66 and 3.66.
That's a different kettle of fish entirely, largely because with the heat pump water heater they're pulling the heat from the inside of your house, forcing you to move it twice when it is cold out. With a combined unit you only move it once, as the other side of the unit is outside.
That's why they're so great for warm climates though. The water heater also cools your house, especially as that heat is then lost down the drain. Everybody in the south should be jumping on these.
There's a lot of different heating systems: If your heating system uses hot water at any point, (baseboards, hydro-air, underfloor, ect,) using a single heat pump makes a LOT of sense.
Personally, I prefer an air-source heat pump hot water tank. It significantly dehumidifies my basement.
Yes, same thing. Heat pump to heat exchanger. This is over 39 years old tech and in common use around Scandinavia and mainland europe. This is ancient technology.
Why not?
They marketing like it's an expensive tech, but it's pretty cheap.
We have been buying heat pump PTAC for the hotels for last 20 years, and price difference is usually 5% between with and without heat pump.
Seems like all companies are colluding with each other for marking up prices.
We somewhat accidentally ended up with a good combo: we have a ventless heat pump dryer, and a heat pump water heater, also in the laundry room. So when doing laundry, the water heater cools the room while the dryer heats it, so they roughly cancel out.
As an aside, HP dryers are really elegant tech, and it's a shame they're not more common. They use the heat pump not just to heat the air in the dryer, but also to condense the moisture back out of it, so just the water can be drained away instead of needing to exhaust the air outside. So you need much less energy overall, and you don't need a dryer vent. The only downside is they're a bit slower, but ours has a resistive backup option for when you need clothes dry asap, so really it's just price.
Heat pump dryers work at a much lower heat as well since much of the heating of a traditional dryer is lost out of the vent. The heat pump condenses the water out of the hot air so you don't lose the heat.
I've stopped needing to sort my clothes out as a result, I used to hate putting synthetics in a regular dryer because they get worn out so fast that way.
I bought a Samsung HP dryer a few years ago and it'd be great except for a terrible design flaw where lint gets trapped in its heat sink fins, turning into a soggy mess.
We have a Whirlpool that I love, but they discontinued it a couple years ago with no replacement, and I can't imagine why. I guess most people just shop on price, so it didn't sell. Like I said, a shame.
They use them a lot in Norway, it's hardly warm there.
I'm in the northern US and am very happy with mine. I self-installed with a county rebate, so the total cost was a Saturday and $700. My old electric unit was EPA rated for $450/year, and the new one has averaged $170/year over 4 years, so I've already broken even.
> government mandate will force enough demand that manufacturers can enjoy some economies of scale
So you want the government to pick winners and you want to do business with a monopoly? This is the opposite of what you would want.
If the product saves me money, and it's _actually_ better, I will buy it in a heartbeat. If you're involving the government it's because one of those things isn't true.
Gas infrastructure is expensive to build and maintain. Often times with tax money. What tend to happen in Europe is that they phase out gas by not building gas lines for new development.