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For anybody in TVA's electricity networks (mostly: Tennessee): they offer an annual promotion to single-family homeowners only to purchase an $1800 AO heatpump waterheater for only $250.
Maths: 85% discount on fancy new waterheater, which also dehumidifies and cools your house (passive result of heatpump).
TVA usually offers this promotion between Thanksgiving and NYE. You can order online from HomeDepot, or walk into a local store [0]. This ends up costing LESS than a new traditional resistive-type heater.
[0] either method: they DO verify SFH (by more than just ZIP code) -- duplexes and contractors not authorized/allowed
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My own $250.00 "TVA homeowner special" (as a licensed electrician):
<https://i.imgur.com/4wCez9u.jpeg> this specific design draws from both bath and bedroom [dual 6" inlets], exhausts into kitchen [single 8" outlet] | utility closet is only 5ft x 4ft (~20sqft)
Don't forget to use a pressure regulator, expansion tank (coldside, only), & (preferably) a sediment filter. Whatever you do: do NOT use a water softener before the tank.
Important caveat:
> You must swap out an old electric unit; switching from gas to electric doesn't qualify.[0]
That’s a bummer; totally would have done this otherwise
[0] https://www.hotwater.com/water-heater-rebates/tva-heat-pump-...
I have a heat pump hot water heater, and it's been awesome. It's ROI has definitely improved with all the energy price spikes. It's located in my garage (I live in Florida) so there's no shortage of hot air for it to use.
> Whatever you do: do NOT use a water softener before the tank.
I'm curious why not? I can't immediately think of a reason why that would be bad, but I admittedly know hardly anything about plumbing.
> which also dehumidifies and cools your house (passive result of heatpump).
Wait do you install these indoors? I get it's pretty hot in Tennessee, but still got some winters? Also isn't noise an issue?
In most of Australia these are installed outdoors. Pool heaters is another one where one could harvest indoor heat.
In MD, they had rebates for gas-fired instant hot water heaters and tanked heat pump water heaters, but not electric instant water heaters.
Makes no sense...
A heat pump could win as the best HVAC technology, though a better drilling for ground-sourced ones. Just a shallow drilling (up to 100m) that works in retrofit mode, such as drilling from the basement, would be a great upgrade:
- No outdoor unit that looks awful in many settings
- works well, even in the coldest winter, without a spike in electricity usage, COP 5
- very reliable with long durability
- super quiet, no ambient noise
- 20% more efficient
Currently, drilling is very disruptive in retrofits, but there is progress in compact techniques that might change the equation.
Disclaimer: angel investor in https://www.flexdrill.at/
Ground source heat pump owner here in the US. The original system was installed in 2007, and the loop field was designed to "best knowledge at the time". Well in the 20 years since then, NREL changed guidance on how far apart and how deep loops need to be installed. Rightly so, because our circa-2007 is "short looped", it's not sufficient for the house loads, but there is nothing we do about it other than putting on more expensive pumps, more expensive antifreeze and live with heat pump compressors dying pre-maturely because they are working at their design limits. All this makes it as expensive as traditional system (and if we tried to go net-zero with solar, the amount of solar required (because it runs so inefficiently) is larger than our roof area.
So I'm looking at a backup gas boiler to take load of the heatpump/ground loop (house has radiant heat).
And they are not quiet. 5-Ton water to water compressors are not quiet.
And the control system (HDX) and amount of expertise required to keep the thing running is a major barrier to getting low cost maintenance.
Maybe a 2026-designed system will work better and actually live up to the hype you talk about, but there are decades of poorly designed and discarded ground loop heat pumps that have "poisoned the well" if you will.
It's usually so much more expensive than an air source heat pump that makes it completely not worth it.
Drilling alone is €10.000. The whole installation of a air/water heat pump is €10.000. Mostly not worth it.
The 'outdoor unit that looks awful' is an interesting quirk especially with US equipment - most Japanese and European residential units actually look fine, I'm not sure why American ones have tended to look especially ugly.
I notice this with electrical stuff too - things like switchboards etc. in residential and light commercial installations we have quite neat stuff that's usually quite streamlined and in light white/grey/cream colours, whereas the switchboards and conduits and thigns I see in videos of US home installations look like grey chunky metal stuff that you'd only see in heavy industrial sites here!
We have a ground-source heat pump for our ADU. We did it because we were curious about just how efficient we could make the house, but I don't expect that it will ever break even financially vs a modern air-source system with resistive backup in our climate (northern New England, typically very few –20˚ nights, –10˚-0˚ more common with daytime highs in the single digits).
It works great, but it's hard to see a way to it making sense for most folks here.
Friends in south Sweden and they got a hole drilled in the front yard like it’s the most normal thing. Is it there?
Borehole or the pipe grid they stick under your backyard/garden (if you have a decent sized one) end up way more expensive.
But tbf, AI and robotics are rolling along pretty well. I'm surprised there's not a company that's just build the "this robot installs your borehole/underground pipes in 3 hours by itself" robot.
Drilling in the basement seems like a pain to remove the dirt you dig up. Saving yourself a couple of feet cannot be worth the access troubles
Drilling only works if you have access to a garden where to drill. Any kind of apartment has to use the outdoor unit
In DACH, there's not really an alternative for many homes. Heat pumps are by now cheaper, more efficient, more versatile and definitely greener than other means of heating.
If you get one, just make sure to get the dimensioning right. They are WAY more complex to plan, install and maintain than traditional heating.
> DACH, an acronym for Deutschland (Germany), Austria, Confoederatio Helvetica (Swiss Confederation), the three major German-speaking countries
I was not familiar with this term before, had to look it up.
>[heatpump waterheaters are] WAY more complex to plan, install
Only if you place them within <700sqft (for a typical indoor residential location). Only in areas smaller will you need to duct them, somewhat similarly to:
<https://i.imgur.com/4wCez9u.jpeg> this specific design draws from both bath and bedroom [dual 6" inlets], exhausts into kitchen [single 8" outlet] | utility closet is only 5ft x 4ft (~20sqft)
As an added bonus it'll passively dehumidify/cool whereever it drafts to/from.
> They are WAY more complex to plan, install and maintain than traditional heating.
I'm curious what about them would be more difficult to plan, install, and maintain. Obviously there are many things to consider when retrofitting a building with a central gas furnace... but otherwise why would they be much more complicated than an air conditioning system?
>In DACH, there's not really an alternative for many homes.
And yet in Austria, most apartment buildings in big cities are still heated by burning heating oil, gas or even firewood. Worst of the worst for air quality.
Walk through Graz in sub-zero winters and it's like you're breathing in a barbeque bonfire. Even your clothes smell like soot when you get home if you've been out too long. Which is bizarre to me, considering how much posturing and chest thumping Austria is doing about how green and anti-Nuclear they are yet they love burring wood and oil. Male this make sense please.
Sure, rich people in the bacon belt living in single family homes in the suburbs or rural areas, have heat pumps, solar panels on the roof and a Tesla in the garage, but that's a different story compared to those living in the city stuck in the fossil fuel stone age, where they have no choice over their rented building's heating method.
How do you convert the city's apartment buildings to heat pumps? Is it a technological limitation? Money limitation? Bureaucratic and political limitation? All of the above?
1) To make it really green and viable -> you „need” solar installation
2) To have solar installation you have to abaid to painfully stupid legistlation
3) In winter pump is as green as the diesel generator that produces energy for it to run
> [it] become[s] cheaper than gas heating within 11 to 14 years
This a no-brainer for buildings with high energy use. But we looked into getting a heat pump last year but it doesn't pan out because our house (15 years old) has a very low energy use and we would not recover the costs (about 20K euros after subsidies) for 20+ years.
Your existing system will not last forever. When you have to spend money anyway that changes things.
With any luck, oil prices will rise enough to make that conversion worthwhile!
> [it] become[s] cheaper than gas heating within 11 to 14 years
They also always stop the savings estimates right before the expected lifespan of the heatpump, at which point you have to buy a new unit which destroys the actual savings
Remember: every heat pump is a semi-permanent move to electricity over other fuels.
People almost never go back. This isn't just a temporary improvement.
Interesting looking at how EV sales plumented.
As a PSA, mini splits are pretty easy to self-install, and it can save you a bundle, even when buying all the equipment new. Lots of youtube videos on how to do it, though I'd add that most of them show using a manifold with analog gauges to do a vacuum test. You should really get a digital micron gauge and pull a deep vacuum.
Also, make sure that's actually legal in your jurisdiction. It is not legal here (primarily due to handling of coolant)
imagine the President of the US and his "braintrust" accidentally making the world much more green and efficient by forcing a radical reduction in oil dependency
while they purposely end climate-change research including destroying billions in observation satellites by deorbiting them
the history written about this decade is going to be wild, if we survive it
I run daily comparisons between a gas boiler and a heat pump in the UK. Given that gas is cheaper than electricity, a well-installed and well-controlled gas boiler can still be cheaper to run. Heat pump running costs can drop drastically when combined with solar and battery storage, but that requires a much greater upfront investment.
I think there's one big issue for massive electrification and insulation of buildings: renting.
As a renter, I have no incentives to invest thousands in my home's betterment because I will have lost those when I am gone. As an owner, I have no incentives to make my apartment/house better because I don't live in it and I don't pay the energy bills.
Something has to be done about that if we want to combat climate change. I know in France it is now forbidden to rent again or sale when the renter leaves if the home's energy grade is F or G (A is best) but it is probably loosely enforced/easy to circumvent. And it is too damn slow ! This is for regulation but maybe there are other levers ?
As a renter I would basically have to wait for energy prices to skyrocket for it to make economic sense. I hate this situation.
“ A total of around 575,000 residential heat pump units were sold across 11 European countries from January to March 2026, up from 494,000 in the same period in 2025”
Not a big increase on a relatively small base. What is the takeaway here?
Governments should have been full bore pushing subsidies and cost breaks for phevs, home solar, evs,and hear pumps for the last decade.
Covid was the wakeup call that globalization was dying a slow death, and the first trump that world cop America was also on the way out.
Oil dependence in a top level national security concern of the last 150 years (hey, what really triggered WW1?), yet the primary means for independence has been politically suppressed for 50 years.
How soon would we have has better PV, better batteries, better heat pumps with proper subsidies and research starting with the 70s oil shocks?
Reading comments here i think many are missing something, all of our summers are getting longer and hotter, we didn’t need air conditioning before.
It’s not just heating anymore, now places need active cooling too.
A significant proportion of the European population will only ever talk about heat pumps when they are in a social setting which allows for free conversation. And they haven't shut up about it for about 20 years now. It used to bore me to death.
Must be nice having more than 3kW available at the breaker
in the south, a lot of people opt for split Airconditioning instead of heatpumps. Cheaper and much easier to install/maintain
That's a neat proxy measurement to track.
They’re pretty efficient
If governments would get their act together and build nuclear power…
End users could have simple resistive heating.
But no, in the name of invitation and net zero, end user are forced to bear the cost and maintenance burden of much more complicated equipment systems.
It’s all arse-backwards.
Shame on The Netherlands: ~89% of homes still use natural gas in some way for heating [1], and their government are now "scrapping the obligation to purchase a heat pump in 2026" [2].
[1] https://www.cbs.nl/en-gb/news/2025/50/ever-more-gas-free-hom... [2] https://www.abnamro.nl/en/personal/specially-for/preferred-b...