The number of households with heat pumps needs to increase tenfold in the rush to net zero — one couple tells Martina Lees how they fitted one on a tight budget
Air to air heat pumps are amazing. I’m completely converted, they are fair superior to gas.
But why the UK is pushing do hard for air to water is a mystery to me. Seems like betting on old inferior technology.
Also I don’t get why they aren’t pushing for a induction also conversion and disconnecting the gas line to the house entirely. Induction is magic, that is a way superior technology to gas cooking.
The big reason somebody might want air to water is that it enables a low-cost retrofit of an existing heating system which uses water to distribute heat. Definitely not what I’d choose if designing from scratch, but I can see how it makes financial sense in a lot of homes.
And yes, induction is amazing, but there are a whole bunch of people who have been marketed into treating gas stoves as their personal identity.
I think most of those retrofits aren’t cheap because the pipes and radiators aren’t big enough for the colder water. So it ends up needing a whole now install anyway.
It’s probably always cheaper. The government is pushing for air to water. There are no subsidies for air to air which I think is a better way to heat a home.
why the UK is pushing do hard for air to water is a mystery to me.
I was a little confused when I followed a European forum. The transition to heat pumps has been a big deal, lot of discussion in the UK and Germany. It had a bunch of people talking about boilers and having heat pumps heat water, which confused me. I’d only heard about boilers in the US much in the context of large buildings with old steam heating systems.
In the US, I’ve seen plenty of air source heat pumps. Some water source heat pumps. But they both are used to heat (or chill) air, which is then blown into ducting and circulated through the house. Provides ventilation and such and humidity control. But it seemed to be overwhelmingly the case that people in Europe were talking about heating water and circulating that.
Small window or through-wall air conditioning units do obviously heat air, usually for one room. Split minis move refrigerant, which ultimately heats or cools air.
And it seems like you’d rather have ducting, as it can provide control over a given ratio of fresh air to an area of a building and filter it.
I was able to find a few companies in the UK dealing with ductwork, but they focused on new office buildings.
I eventually figured out what was going on.
A lot of houses in the US were built after the introduction of air conditioning. Not only that, but the US has more areas that get quite hot than Europe, so once air conditioning was an option, people really wanted it. The result is that a lot of US housing was built with central air conditioning.
This meant that when houses were designed, ductwork was built into the design.
Ducts are relatively-large. It takes a lot of space to move a given amount of heat.
It is not easy to retrofit ducting into an existing house. You have to have this big thing jammed into the house somewhere that runs to all rooms.
Water is much denser. If you use water to move your heat around, you don’t require that much space. So if you retrofit an existing house, you don’t have to mess the house up. Not only that, but a lot of buildings in the UK had apparently already been set up with systems that heated water with natural gas and then moved it around the building to heat it, so putting in a heat pump could use that existing system.
My guess is that people did the math and decided that it didn’t make sense to massively go rip up existing houses when they could stick comparatively-unobtrusive additional water pipe in.
My guess is that what will happen is that new buildings will incorporate ductwork, so there will be a very slow transition to ductwork. But it won’t happen overnight, just as buildings age out and are demolished.
The current transition to heat pumps that they’re doing is on a much shorter timeline than that.
The air to water thing is huge in the Netherlands too. I think it is because it’s the traditional way of heating the house. So people looking to replace it will want the same thing.
It’s even so that the word heat pump only is used for the air-water units, not the air-air ones, those are called airconditioners.
We changed to an electric boiler and air heat pumps, and have archived quite the reduction, certainly when the gas price went sky high.
It’s even so that the word heat pump only is used for the air-water units, not the air-air ones, those are called airconditioners.
The names and tech all overlap and it gets messy. But you can certainly buy an ac unit that doesn’t heat. Hence why I specified heat pump, it is a heat pump.
On the other hand, using a heat pump for replacing a hot water heater is definitely a good thing. Using a heat pump on an old water radiator system may not work well. Friends had to replace a gas heater for their water radiator system and were told that there wasn’t a heat pump unit hot enough for the retrofit.
Oh yea. I’ve been in houses (outside the UK). Had heat pump water tank and an air to air heating (and ac) system for the house.
I’ve always wondered if you could have an air to water system that fills the tank for the taps and then heats the radiators. But also have supplementary heating air to air. Maybe a big one downstairs in the hallway or in the main room of the house.
But with the UK it always comes back to having the worst insulation in the world. Fix that and we wouldn’t even be discussing heating systems.
Temperatures do not often switch between great extremes, with warm summers and mild winters.
The British Isles undergo very small temperature variations. This is due to its proximity to the Atlantic, which acts as a temperature buffer, warming the Isles in winter and cooling them in summer.
Over here, in the US, the places with the lowest temperature variations are also islands, like Hawaii. Extreme temperature swings happen in places like the Dakotas, far away from the ocean.
You’ve been cursed with fairly comfortable temperatures. :-)
Oh, and one other factor. I was just reading a paper on British housing policy. I’m not taken with the format – it’s imagining a world where planning restrictions on building new housing were reduced, and talking about the benefits of it – but it does also make a number of good points, including the point that some of it is that the UK hasn’t been building housing at the kind of rate that would probably be ideal for some time. Since newer buildings are better-insulated, that also means that the present stock of buildings tend to be less-well-insulated than would be the case had more construction occurred:
Although this was not initially the motivation, there have been environmental
benefits as well. For a long time, Britain used to have poorer energy
efficiency standards than most neighbouring countries. It is not that all
British homes were energy inefficient. It is just that Britain used to have
the oldest housing stock in Europe (European Commission n.d.), and the
energy efficiency standard of a dwelling is strongly correlated with its age
(ONS 2022). Rejuvenating the housing stock has therefore accidentally
driven up its average energy performance.
This is the “the paper is from a potential future looking back at the imaginary past” format talking here.
In Australia, we have followed the British housing tradition and have really bad insulation too! We are working on fixing it but there is so much to retrofit.
I hate induction with a passion, beep boop it doesn’t work because a drop of water, you can’t put anything on it, the controls are obnoxious and you have to change at least some cookwear.
I love gas, sure it’s more a preference than logic but it’s so snappy ! Turn the button and you have 5000watts of heat, no long click this, short click that, and when done, just turn the knob.
Now, it has drawbacks like when it’s windy, it does get super hot etc. but I’d get hologen (with knobs) before any induction.
Sounds like you hate lack of knobs rather than induction. Just get one with knobs.
Induction works when you spill water on it, I’ve done it.
Instant heat. Excellent all over heat transfer. Doesn’t heat the room. No cancer causing pollution. Good for the environment. Specific heat control where you can set power and even temperature. Easy to clean.
Tbf there is some differences in quality between them. Some work exactly as you want and others are annoying because they don’t do what you expect. When they work I find them a dream.
The problem with induction (including everything you cited there) is down to implementation, not the tech itself. The difference in UX between a bad induction stove and a good one is far far greater than the difference between a bad and good gas stove. A bad induction stove is just… really bad. But a good one (knobs, high density of settings) is just amazing. You can command 3000+W of power that actually goes where you want (you can get a pot of pasta water boiling in like 2 mins), and then the same element than consistency simmer at whatever low level you want indefinitely.
After using a great induction stove (with knobs, knobs are mandatory) I can’t ever go back. Yeah you get 5000 watts of heat with gas but most of that just heats your kitchen, face, and pot handles. It only tangentially interacts with the food you’re trying to cook.
My main issue with induction conceptually (once you move to induction compatible cookware) is that because they need to be digitally controlled they’re necessarily complicated. It’s possible for a gas stove to last 100 years if it’s high quality and well maintained. An induction stove is lucky to last 10. But the experience is sufficiently superior for me.
Air to air heat pumps are amazing. I’m completely converted, they are fair superior to gas.
But why the UK is pushing do hard for air to water is a mystery to me. Seems like betting on old inferior technology.
Also I don’t get why they aren’t pushing for a induction also conversion and disconnecting the gas line to the house entirely. Induction is magic, that is a way superior technology to gas cooking.
The big reason somebody might want air to water is that it enables a low-cost retrofit of an existing heating system which uses water to distribute heat. Definitely not what I’d choose if designing from scratch, but I can see how it makes financial sense in a lot of homes.
And yes, induction is amazing, but there are a whole bunch of people who have been marketed into treating gas stoves as their personal identity.
I think most of those retrofits aren’t cheap because the pipes and radiators aren’t big enough for the colder water. So it ends up needing a whole now install anyway.
I can see how that could happen for some homes. Worth doing the calculation though, since it can be cheaper if the pipes are adequate.
It’s probably always cheaper. The government is pushing for air to water. There are no subsidies for air to air which I think is a better way to heat a home.
I was a little confused when I followed a European forum. The transition to heat pumps has been a big deal, lot of discussion in the UK and Germany. It had a bunch of people talking about boilers and having heat pumps heat water, which confused me. I’d only heard about boilers in the US much in the context of large buildings with old steam heating systems.
In the US, I’ve seen plenty of air source heat pumps. Some water source heat pumps. But they both are used to heat (or chill) air, which is then blown into ducting and circulated through the house. Provides ventilation and such and humidity control. But it seemed to be overwhelmingly the case that people in Europe were talking about heating water and circulating that.
Small window or through-wall air conditioning units do obviously heat air, usually for one room. Split minis move refrigerant, which ultimately heats or cools air.
And it seems like you’d rather have ducting, as it can provide control over a given ratio of fresh air to an area of a building and filter it.
I was able to find a few companies in the UK dealing with ductwork, but they focused on new office buildings.
I eventually figured out what was going on.
A lot of houses in the US were built after the introduction of air conditioning. Not only that, but the US has more areas that get quite hot than Europe, so once air conditioning was an option, people really wanted it. The result is that a lot of US housing was built with central air conditioning.
This meant that when houses were designed, ductwork was built into the design.
Ducts are relatively-large. It takes a lot of space to move a given amount of heat.
It is not easy to retrofit ducting into an existing house. You have to have this big thing jammed into the house somewhere that runs to all rooms.
Water is much denser. If you use water to move your heat around, you don’t require that much space. So if you retrofit an existing house, you don’t have to mess the house up. Not only that, but a lot of buildings in the UK had apparently already been set up with systems that heated water with natural gas and then moved it around the building to heat it, so putting in a heat pump could use that existing system.
My guess is that people did the math and decided that it didn’t make sense to massively go rip up existing houses when they could stick comparatively-unobtrusive additional water pipe in.
My guess is that what will happen is that new buildings will incorporate ductwork, so there will be a very slow transition to ductwork. But it won’t happen overnight, just as buildings age out and are demolished.
The current transition to heat pumps that they’re doing is on a much shorter timeline than that.
The air to water thing is huge in the Netherlands too. I think it is because it’s the traditional way of heating the house. So people looking to replace it will want the same thing.
It’s even so that the word heat pump only is used for the air-water units, not the air-air ones, those are called airconditioners.
We changed to an electric boiler and air heat pumps, and have archived quite the reduction, certainly when the gas price went sky high.
But there is a lot of resistance to the idea.
The names and tech all overlap and it gets messy. But you can certainly buy an ac unit that doesn’t heat. Hence why I specified heat pump, it is a heat pump.
On the other hand, using a heat pump for replacing a hot water heater is definitely a good thing. Using a heat pump on an old water radiator system may not work well. Friends had to replace a gas heater for their water radiator system and were told that there wasn’t a heat pump unit hot enough for the retrofit.
Oh yea. I’ve been in houses (outside the UK). Had heat pump water tank and an air to air heating (and ac) system for the house.
I’ve always wondered if you could have an air to water system that fills the tank for the taps and then heats the radiators. But also have supplementary heating air to air. Maybe a big one downstairs in the hallway or in the main room of the house.
But with the UK it always comes back to having the worst insulation in the world. Fix that and we wouldn’t even be discussing heating systems.
Most of the UK has relatively-comfortable temperatures, so the impetus to add lots of insulation is relatively low.
https://en.wikipedia.org/wiki/Climate_of_the_British_Isles
Over here, in the US, the places with the lowest temperature variations are also islands, like Hawaii. Extreme temperature swings happen in places like the Dakotas, far away from the ocean.
You’ve been cursed with fairly comfortable temperatures. :-)
Oh, and one other factor. I was just reading a paper on British housing policy. I’m not taken with the format – it’s imagining a world where planning restrictions on building new housing were reduced, and talking about the benefits of it – but it does also make a number of good points, including the point that some of it is that the UK hasn’t been building housing at the kind of rate that would probably be ideal for some time. Since newer buildings are better-insulated, that also means that the present stock of buildings tend to be less-well-insulated than would be the case had more construction occurred:
https://iea.org.uk/wp-content/uploads/2024/03/IEA-Discussion-Paper-123_Home-Win_web.pdf
This is the “the paper is from a potential future looking back at the imaginary past” format talking here.
In Australia, we have followed the British housing tradition and have really bad insulation too! We are working on fixing it but there is so much to retrofit.
This generally means that they’d need to upgrade their radiators to accommodate a heat pump at normal temperatures.
Sadly that was not the advice that they got.
I’ve been considering getting a multi unit airco (the warms)
For heat pumps I’d need to replace all my radiators
I hate induction with a passion, beep boop it doesn’t work because a drop of water, you can’t put anything on it, the controls are obnoxious and you have to change at least some cookwear.
I love gas, sure it’s more a preference than logic but it’s so snappy ! Turn the button and you have 5000watts of heat, no long click this, short click that, and when done, just turn the knob.
Now, it has drawbacks like when it’s windy, it does get super hot etc. but I’d get hologen (with knobs) before any induction.
/Rant off
Sounds like you hate lack of knobs rather than induction. Just get one with knobs.
Induction works when you spill water on it, I’ve done it.
Instant heat. Excellent all over heat transfer. Doesn’t heat the room. No cancer causing pollution. Good for the environment. Specific heat control where you can set power and even temperature. Easy to clean.
Well spotted!
Maybe I have only used crappy ones in AirBnBs who stopped working if a drop of water touched the plate…
Tbf there is some differences in quality between them. Some work exactly as you want and others are annoying because they don’t do what you expect. When they work I find them a dream.
So a reasonably expensive one I guess, which would be fair I think.
The problem with induction (including everything you cited there) is down to implementation, not the tech itself. The difference in UX between a bad induction stove and a good one is far far greater than the difference between a bad and good gas stove. A bad induction stove is just… really bad. But a good one (knobs, high density of settings) is just amazing. You can command 3000+W of power that actually goes where you want (you can get a pot of pasta water boiling in like 2 mins), and then the same element than consistency simmer at whatever low level you want indefinitely.
After using a great induction stove (with knobs, knobs are mandatory) I can’t ever go back. Yeah you get 5000 watts of heat with gas but most of that just heats your kitchen, face, and pot handles. It only tangentially interacts with the food you’re trying to cook.
My main issue with induction conceptually (once you move to induction compatible cookware) is that because they need to be digitally controlled they’re necessarily complicated. It’s possible for a gas stove to last 100 years if it’s high quality and well maintained. An induction stove is lucky to last 10. But the experience is sufficiently superior for me.