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.
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.
>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.
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 building's heating method where they rent because the landlords and city don't have money or don't care.
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.
That depends on climate. The longer and colder your winters are, the more you benefit from the reliable efficiency of a ground source. Ground source heat pumps have been the most common choice for heating new single-family homes in Finland for the last ~20 years.
Installation is probably relatively cheaper there due to volume too. In areas where it is less common, there is less competition and fewer options for competent installers.
Yeah, recently saw some numbers for air-to-air vs air-to-groundwater, and it break even after more than 25 years, with more than twice the initial cost
To jakozaur’s point, there’s plenty of reasons drilling can get cheaper and there’s at least one other company working on it [1]—would love to hear about others! I’m a minimally informed amateur but my intuition is that the way it’s typically done (multiple inch borehole, U-tube geometry) is fairly suboptimal since the diameter is a lot wider than you need it to be just for hydrodynamic resistance and you get losses from the outgoing liquid cooling the incoming liquid. Dropping the diameter should make drilling a lot easier—-you can sink a 5/8”x12’ ground rod with hand tools in the right soil! (you’d still have to figure out how to make the holes meet up but I imagine there are ways of doing this).
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.
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.
Out of curiosity, has the demand stayed the same? I'm asking because you see the same with electricity grids, designed in a different time with much lower demand.
Sorry to hear this, it seems like a great system to me but you have to have the capacity right. I'm planning on getting one in the next year but the drilling will be more than we need and we opt for no glycol (yet) as that also gives us headroom
If you're an individual with an apartment you don't have the choice to drill.
If you're building the apartment building you have the choice to drill for the entire building, and the number of units that benefit mean this is much more cost efficient than with single family homes.
> [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.
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
EU severely reducing its fossil fuel imports from Russia in 2022 cut down natural gas usage by 17% and overall energy consumption by 3%. So yeah, increased price due to scarcity help a lot in shifting around the energy mix.
It's a bit shit that hits poorer people relatively more than richer people. Governments can reduce this impact by subsidizing sustainable alternatives (like heat pumps). It's still leading to inequality (unless you give more subsidy to the poor), but at least overall people will hopefully benefit.
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.
https://x.com/AO7186252340513
https://bsky.app/profile/showpiece.bsky.social
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.
>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.
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 building's heating method where they rent because the landlords and city don't have money or don't care.
How do you fix that?
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/
It's usually so much more expensive than an air source heat pump that makes it completely not worth it.
That depends on climate. The longer and colder your winters are, the more you benefit from the reliable efficiency of a ground source. Ground source heat pumps have been the most common choice for heating new single-family homes in Finland for the last ~20 years.
Installation is probably relatively cheaper there due to volume too. In areas where it is less common, there is less competition and fewer options for competent installers.
Yeah, recently saw some numbers for air-to-air vs air-to-groundwater, and it break even after more than 25 years, with more than twice the initial cost
What were the figures and where are you?
Drilling alone is €10.000. The whole installation of a air/water heat pump is €10.000. Mostly not worth it.
To jakozaur’s point, there’s plenty of reasons drilling can get cheaper and there’s at least one other company working on it [1]—would love to hear about others! I’m a minimally informed amateur but my intuition is that the way it’s typically done (multiple inch borehole, U-tube geometry) is fairly suboptimal since the diameter is a lot wider than you need it to be just for hydrodynamic resistance and you get losses from the outgoing liquid cooling the incoming liquid. Dropping the diameter should make drilling a lot easier—-you can sink a 5/8”x12’ ground rod with hand tools in the right soil! (you’d still have to figure out how to make the holes meet up but I imagine there are ways of doing this).
[1] https://www.borobotics.ch/
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.
You might still get the most out of it when the AMOC collapses.
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
Friends in south Sweden and they got a hole drilled in the front yard like it’s the most normal thing. Is it there?
The challenge is for people who live in apartment buildings in urban environment where you have no front yard you can drill into at your leisure.
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.
Out of curiosity, has the demand stayed the same? I'm asking because you see the same with electricity grids, designed in a different time with much lower demand.
Sorry to hear this, it seems like a great system to me but you have to have the capacity right. I'm planning on getting one in the next year but the drilling will be more than we need and we opt for no glycol (yet) as that also gives us headroom
Drilling only works if you have access to a garden where to drill. Any kind of apartment has to use the outdoor unit
If you're an individual with an apartment you don't have the choice to drill.
If you're building the apartment building you have the choice to drill for the entire building, and the number of units that benefit mean this is much more cost efficient than with single family homes.
In sensible countries each housing unit have a central heating solution, regardless of where the heat comes from.
> [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.
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.
I am probably simply confused but what’s the proxy measurement?
I assume a product related directly to another product. So when energy prices start to go up, invest in heat pump companies.
Thats what I was guessing but was thrown off because it is a pretty natural nth order effect. Gas prices go up, more efficient cars get sold.
More efficient hvac tech is a partial substitute for fuel.
Heat pump sales for energy costs.
with no evidence I give credit to this awesome video: https://youtu.be/7J52mDjZzto?si=bgkEC0wCUqaFCie2
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
EU severely reducing its fossil fuel imports from Russia in 2022 cut down natural gas usage by 17% and overall energy consumption by 3%. So yeah, increased price due to scarcity help a lot in shifting around the energy mix.
It's a bit shit that hits poorer people relatively more than richer people. Governments can reduce this impact by subsidizing sustainable alternatives (like heat pumps). It's still leading to inequality (unless you give more subsidy to the poor), but at least overall people will hopefully benefit.