I got a heat pump installed, with an air handler to push the air through our ducts, in place of our old gas furnace in Seattle. I love it! But FYI the whole install cost $16k in 2021, and friends doing it now say it's well over $20k. Maybe we are all getting ripped off, but that was the lowest bid from several fully booked companies. I think it mostly points to our need for more electricians and HVAC technicians to scale up the installation of these great machines in capacity-constrained cities.
The problem is old homes that don’t have a central a/c. They’d require very expensive and extensive retrofits to accommodate a central air heat pump.
But that’s where mini-splits can come in. With those units you can add heat pumps (and cooling, incidentally) to any room in the house without an ugly window unit. They’re super efficient (even more so than central source heat pumps) and less costly / complex to install.
A new development that I'm quite excited about is combining a heat pump with controls that let you treat your hot water tank as a thermal battery: https://www.harvest-thermal.com/
When energy is cheap (like, when your PV system is pumping out more than you need), you run the heat-pump to soak up some of that extra, and pack heat into a very well-insulated water tank. Then at night when you don't have energy, you get your hot water by down-mixing the super-hot water with cold; and you get air heat by running the air through a heat-exchanger fed with the super-hot water.
The concern around heat-pumps working in cold regions always confused me because the place where heat pumps are and have been dominant for decades is... Scandinavia. And it famously gets cold here! I'm American, but live in Sweden, and my eyes have been opened to the potential of what is now a very mature and dominant technology here.
My Swedish MIL has had a ground-source or geothermal heat-pump for almost as long as I've been alive. It produces cheap, reliable heat for both her century-old radiators and hot water tank. For these geothermal units, you basically dig a borehole at least 100m down under or near the house, run a refrigerant coil loop down into it with a simple electric pump and compressor in your basement (like your fridge), and and utilize the fact that the ground is warmer than the winter air. Her house is a century-old, wood house and not very well-insulated, but her heating bill is almost nothing even in the depths of winter in a place where the lows often hit -30C (-22F).
We just installed a heat-pump ourselves that works a little differently. It's an air-source heat-pump. Because we live very near the water, it's harder to dig a borehole to the bedrock, so, instead, we have this very large air intake box outside the house that works like a "reverse AC," sucking in ambient air and using it to heat refrigerant and pressure differentials. This works even when it's very cold outside. Down to about -15C (5F), it's working very efficiently. Below that, the machine needs to kick in with direct electric heating, which is more expensive. Again, it would be better to have a ground-source pump like my MIL, to accommodate even lower temperatures, but this is fine most of the time, as the winter lows below that aren't so frequent and you can heat up the house in the middle of the day when the sun is up and it's less cold, with the house acting as a thermal battery through the lows overnight. Either way, this system was so much more efficient and cheaper than our legacy fuel oil boiler than it paid for itself within only 3 years!
Air-source heat-pumps can use the heat to heat up the legacy radiator system in your house (plus the hot-water tank), like ours, if your need for air-conditioning is minimal. Or, for American houses where it can get cold in the winter and also hot in the summer, you can get an air-source heat-pump that blows the heat inside via vents and also can kick into reverse to blow cold air through the same vents, essentially acting like a dual air-heat and AC system, in one. These are the kind you're seeing proliferate across the American South. They're a really good option across the (generally warmer) United States. If you lived in and older house in Maine with radiators, however, I would recommend a system that just specializes in heating hot water and radiator heating, only. They're more efficient at the single-job, minus the AC capability.
My neighbor has a third type of heat-pump: instead of a borehole or an air-source fan, it has coils buried underneath their entire backyard. Like geothermal heating, this takes advantage of the fact that the ground is much warmer than the air below the frost-line, about 40cm down. It's somewhere between my MIL's geothermal borehole heat-pump and our air-source heat pump in efficiency in the coldest weather. We didn't go for this option ourselves because it requires digging up the whole yard, adding some up-front costs and inconvenience. But this is an excellent format for cold places, even those like ours near water.
There's a fourth type of heat-pump for waterside houses: the water-source heat-pump. You run the coil under the water near your house, which takes advantage of how lakewater is warmer deeper down, below where it ices over in the coldest winter. Another excellent option for cold places near water.
Though heat-pumps are almost always a superior option both practically and financially, the realistic limit on all this stuff is what your local contractor base has experience with. They may not be familiar with heat-pumps at all, or else only know how to install the air-source kind (bore-holing is a whole other capability). Heat pumps are more expensive and complicated to install, initially, so you need somebody good and a network of experienced HVAC contractors who can fix it later. My American mom didn't go for one in Maryland after both her heating and cooling system gave out last year for this reason: there just weren't any contractors who were offering this service in her area. That's a real shame because she spent way more replacing a natural gas boiler and AC system recently that will now run in her house for the next 15-20 years and the total cost of ownership will be higher.
Your piece is funny and generally accurate. There is a LOT of nonsense in these comments. I won’t bother responding — it’s pretty clear who’s a whackadoodle. I’ll push back against one claim you make uneccessarily in the article: ANYTHING electric is a potential source for a fire. I live in Florida, in a very old house, and we use a hybrid system that produces very good AC during our long summers, and that also works admirably well (not great, but good enough) to provide warm air for cold nights in December. I’m not a great elctrician, but a pretty good one, and give me an hour to bridge some switches and break some parts, and I guarantee you that my house (wood) would burn to the ground. Heat pumps are safe and reliable, but not foolproof. tl;dr: What you said, minus the whole “heat pumps can’t cause fires.” Never make claims that are unnecessary and critics will seize upon. “Relative to furnaces that burn oil, heat pumps are far safer when it comes to fires.” Something like that….
I looked into having a heat pump installed for pool cooling - I live in California - and I was told they don't function as well in a dry climate so that wouldn't be a good solution. Instead, we installed a solar system that pulls the water through pipes on the roof at night to dissipate the heat.
In Australia we call space-oriented heat pumps “reverse cycle air conditioners” and they have become very typical in recent years for cooling purposes with occasional heating benefits (we don’t have harsh winters where anybody much lives, though my home city Melbourne gets fairly grey and coldish, and has a lot of gas space heating.)
Heat pumps for water heating are also an interesting topic too (and way less common here so far!)
The main problem with heat pumps is the same problem we have with solar and electric cars. The electricity grid is 50 years at least away from being good enough to cope. New solar projects in the UK are being told, "we might be able to connect you in 2030 if your lucky". If our idiotic politicians carry on pushing this (in lockstep with out global overlords) the only result will be poverty and inflation. If they were serious about the environment surely the first thing is to ban private jets and megayachts. Instead we are all going to pay, possibly with out lives.
What! The black, brown and LGBT unsafe state of Florida led by the fascist and vile Ron DeSantis and populated with racist conservatives... leads the way in environmentally friendly home climate control! Say it isn't so, Noah! Please!
More seriously, I had a heat pump on my house as a kid in the 1980's. Low maintenance, efficient, quiet, and unpolluting. What's not to like? Had I remembered 10 years ago when I redid my own HVAC, I would have put one on this house. But when you're a kid you don't notice things like that.
Heat pumps are marginal at best in many places. Your -15F (-20C?) citation is a perfect example. They can work, but anywhere with those temps exist also likely to see colder, and require a gas or electric furnace backup. That makes the ROI beyond the life of the heat pump any time I've tried to run the numbers. It does not help that heat pumps are just plain pricey.
Electric backup in particular blows the whole economic argument out of the water. Electric heating is so much more expensive than gas, particularly for backup in jurisdictions where fixed costs will dominate the bill, and one otherwise doesn't need utility power.
In Canada, outside southern Ontario and the Vancouver area, they are being installed by homeowners who are getting duped.
Such a one-sided article with no mention of the weaknesses of the technology. It makes me question if all articles here are written so one-sidedly here.
The plain fact is that if you live in an actually COLD climate, like Chicago or Minneapolis, where it goes below 32F outside for weeks at a time, notably NOT Seattle, then you will need to wear a coat indoors to feel comfortable during the depths of winter. When someone claims to be from a cold country and they love their heat pump, ask them what temp they keep their house at; they will probably say 62F and they have to wear full layers to make that work since a heat pump house feels colder at the same temp as a furnace-warmed house!!! If you are from a temperate climate and are proselytizing for heat pumps, please broaden your horizons, note what temp you keep your house at, how cold it gets during winter, how many layers you wear INSIDE the house during winter, and go some place cold during the winter to learn about the world.
Note that using electricity from the grid is not green by definition since it depends on where you live. If you live in areas in Canada, where hydroelectric feeds the electrical grid, then yes the electricity from your wall is green. BUT if you live in Texas or other states where coal is used to generate electricity, then your electricity is NOT "green"; your house and your EV is running off COAL and that will not change any time soon since there are not enough renewables to feed the energy needs of the US.
We moved into a condo a year ago and lucked out in that all the units have individual heat pumps for climate control. We are not at the mercy of the building when we want to turn on the heat or AC and because the unit is also well insulated, our utility bills are 1/4 of our old house.
"It means that heat pumps aren’t being subjected to the same kind of pointless culture war that has hindered the implementation of ... induction stoves."
Not pointless for those of us who like good food and care about cooking, and don't want the federal government micromanaging how we cook our food. Note that the culture war about gas stoves only began when a commissioner of the Consumer Public Safety Commission stated in an interview that he wished to ban gas stoves altogether. Also note that this madness was based on a spate of very sketchy, speculative studies that have now largely been debunked. This was far from "pointless" outrage, and isn't something that conservatives fabricated out of the blue.
As for heat pumps, they sound great in terms of efficiency gain. The big concern, as with all purely electric appliances, is what happens when the power goes out. I used to live in a mountainous, rural-ish, very snowy region of California. Winter power outages were a frequent occurrence, often for days at a time. Much more frequent than gas outages.
On the positive side: I've heard a lot of groaning from degrowther types about how air conditioning is bad and evil and should be heavily restricted. Perhaps wider adoption of heat pumps could counteract the outdoor warming effect of summer AC by dumping out colder air in the winter?
If they work, they are fine and super savers to boot. More than half of my friends experience issues of different sorts. Still a half baked tech, i guess. Needs further developement.
I was told by some HVAC pros that in Minnesota, I cannot have a heat pump installed without a backup source of heat, due to the heat pumps not working in temps below -13.
No discussion of heat pumps would be complete without a discussion of the refrigerants used in heat pumps. These refrigerants can cause serious environmental problems if/when released into the atmosphere, as is often the case [in particular in poorly regulated places like China, India, Africa and South America]. The mass deployment of heat pumps/air conditioners in those places is an environmental disaster already in process.
I got a heat pump installed, with an air handler to push the air through our ducts, in place of our old gas furnace in Seattle. I love it! But FYI the whole install cost $16k in 2021, and friends doing it now say it's well over $20k. Maybe we are all getting ripped off, but that was the lowest bid from several fully booked companies. I think it mostly points to our need for more electricians and HVAC technicians to scale up the installation of these great machines in capacity-constrained cities.
The problem is old homes that don’t have a central a/c. They’d require very expensive and extensive retrofits to accommodate a central air heat pump.
But that’s where mini-splits can come in. With those units you can add heat pumps (and cooling, incidentally) to any room in the house without an ugly window unit. They’re super efficient (even more so than central source heat pumps) and less costly / complex to install.
A new development that I'm quite excited about is combining a heat pump with controls that let you treat your hot water tank as a thermal battery: https://www.harvest-thermal.com/
When energy is cheap (like, when your PV system is pumping out more than you need), you run the heat-pump to soak up some of that extra, and pack heat into a very well-insulated water tank. Then at night when you don't have energy, you get your hot water by down-mixing the super-hot water with cold; and you get air heat by running the air through a heat-exchanger fed with the super-hot water.
The concern around heat-pumps working in cold regions always confused me because the place where heat pumps are and have been dominant for decades is... Scandinavia. And it famously gets cold here! I'm American, but live in Sweden, and my eyes have been opened to the potential of what is now a very mature and dominant technology here.
My Swedish MIL has had a ground-source or geothermal heat-pump for almost as long as I've been alive. It produces cheap, reliable heat for both her century-old radiators and hot water tank. For these geothermal units, you basically dig a borehole at least 100m down under or near the house, run a refrigerant coil loop down into it with a simple electric pump and compressor in your basement (like your fridge), and and utilize the fact that the ground is warmer than the winter air. Her house is a century-old, wood house and not very well-insulated, but her heating bill is almost nothing even in the depths of winter in a place where the lows often hit -30C (-22F).
We just installed a heat-pump ourselves that works a little differently. It's an air-source heat-pump. Because we live very near the water, it's harder to dig a borehole to the bedrock, so, instead, we have this very large air intake box outside the house that works like a "reverse AC," sucking in ambient air and using it to heat refrigerant and pressure differentials. This works even when it's very cold outside. Down to about -15C (5F), it's working very efficiently. Below that, the machine needs to kick in with direct electric heating, which is more expensive. Again, it would be better to have a ground-source pump like my MIL, to accommodate even lower temperatures, but this is fine most of the time, as the winter lows below that aren't so frequent and you can heat up the house in the middle of the day when the sun is up and it's less cold, with the house acting as a thermal battery through the lows overnight. Either way, this system was so much more efficient and cheaper than our legacy fuel oil boiler than it paid for itself within only 3 years!
Air-source heat-pumps can use the heat to heat up the legacy radiator system in your house (plus the hot-water tank), like ours, if your need for air-conditioning is minimal. Or, for American houses where it can get cold in the winter and also hot in the summer, you can get an air-source heat-pump that blows the heat inside via vents and also can kick into reverse to blow cold air through the same vents, essentially acting like a dual air-heat and AC system, in one. These are the kind you're seeing proliferate across the American South. They're a really good option across the (generally warmer) United States. If you lived in and older house in Maine with radiators, however, I would recommend a system that just specializes in heating hot water and radiator heating, only. They're more efficient at the single-job, minus the AC capability.
My neighbor has a third type of heat-pump: instead of a borehole or an air-source fan, it has coils buried underneath their entire backyard. Like geothermal heating, this takes advantage of the fact that the ground is much warmer than the air below the frost-line, about 40cm down. It's somewhere between my MIL's geothermal borehole heat-pump and our air-source heat pump in efficiency in the coldest weather. We didn't go for this option ourselves because it requires digging up the whole yard, adding some up-front costs and inconvenience. But this is an excellent format for cold places, even those like ours near water.
There's a fourth type of heat-pump for waterside houses: the water-source heat-pump. You run the coil under the water near your house, which takes advantage of how lakewater is warmer deeper down, below where it ices over in the coldest winter. Another excellent option for cold places near water.
Though heat-pumps are almost always a superior option both practically and financially, the realistic limit on all this stuff is what your local contractor base has experience with. They may not be familiar with heat-pumps at all, or else only know how to install the air-source kind (bore-holing is a whole other capability). Heat pumps are more expensive and complicated to install, initially, so you need somebody good and a network of experienced HVAC contractors who can fix it later. My American mom didn't go for one in Maryland after both her heating and cooling system gave out last year for this reason: there just weren't any contractors who were offering this service in her area. That's a real shame because she spent way more replacing a natural gas boiler and AC system recently that will now run in her house for the next 15-20 years and the total cost of ownership will be higher.
Your piece is funny and generally accurate. There is a LOT of nonsense in these comments. I won’t bother responding — it’s pretty clear who’s a whackadoodle. I’ll push back against one claim you make uneccessarily in the article: ANYTHING electric is a potential source for a fire. I live in Florida, in a very old house, and we use a hybrid system that produces very good AC during our long summers, and that also works admirably well (not great, but good enough) to provide warm air for cold nights in December. I’m not a great elctrician, but a pretty good one, and give me an hour to bridge some switches and break some parts, and I guarantee you that my house (wood) would burn to the ground. Heat pumps are safe and reliable, but not foolproof. tl;dr: What you said, minus the whole “heat pumps can’t cause fires.” Never make claims that are unnecessary and critics will seize upon. “Relative to furnaces that burn oil, heat pumps are far safer when it comes to fires.” Something like that….
I looked into having a heat pump installed for pool cooling - I live in California - and I was told they don't function as well in a dry climate so that wouldn't be a good solution. Instead, we installed a solar system that pulls the water through pipes on the roof at night to dissipate the heat.
In Australia we call space-oriented heat pumps “reverse cycle air conditioners” and they have become very typical in recent years for cooling purposes with occasional heating benefits (we don’t have harsh winters where anybody much lives, though my home city Melbourne gets fairly grey and coldish, and has a lot of gas space heating.)
Heat pumps for water heating are also an interesting topic too (and way less common here so far!)
The main problem with heat pumps is the same problem we have with solar and electric cars. The electricity grid is 50 years at least away from being good enough to cope. New solar projects in the UK are being told, "we might be able to connect you in 2030 if your lucky". If our idiotic politicians carry on pushing this (in lockstep with out global overlords) the only result will be poverty and inflation. If they were serious about the environment surely the first thing is to ban private jets and megayachts. Instead we are all going to pay, possibly with out lives.
What! The black, brown and LGBT unsafe state of Florida led by the fascist and vile Ron DeSantis and populated with racist conservatives... leads the way in environmentally friendly home climate control! Say it isn't so, Noah! Please!
More seriously, I had a heat pump on my house as a kid in the 1980's. Low maintenance, efficient, quiet, and unpolluting. What's not to like? Had I remembered 10 years ago when I redid my own HVAC, I would have put one on this house. But when you're a kid you don't notice things like that.
Heat pumps are marginal at best in many places. Your -15F (-20C?) citation is a perfect example. They can work, but anywhere with those temps exist also likely to see colder, and require a gas or electric furnace backup. That makes the ROI beyond the life of the heat pump any time I've tried to run the numbers. It does not help that heat pumps are just plain pricey.
Electric backup in particular blows the whole economic argument out of the water. Electric heating is so much more expensive than gas, particularly for backup in jurisdictions where fixed costs will dominate the bill, and one otherwise doesn't need utility power.
In Canada, outside southern Ontario and the Vancouver area, they are being installed by homeowners who are getting duped.
Such a one-sided article with no mention of the weaknesses of the technology. It makes me question if all articles here are written so one-sidedly here.
The plain fact is that if you live in an actually COLD climate, like Chicago or Minneapolis, where it goes below 32F outside for weeks at a time, notably NOT Seattle, then you will need to wear a coat indoors to feel comfortable during the depths of winter. When someone claims to be from a cold country and they love their heat pump, ask them what temp they keep their house at; they will probably say 62F and they have to wear full layers to make that work since a heat pump house feels colder at the same temp as a furnace-warmed house!!! If you are from a temperate climate and are proselytizing for heat pumps, please broaden your horizons, note what temp you keep your house at, how cold it gets during winter, how many layers you wear INSIDE the house during winter, and go some place cold during the winter to learn about the world.
Note that using electricity from the grid is not green by definition since it depends on where you live. If you live in areas in Canada, where hydroelectric feeds the electrical grid, then yes the electricity from your wall is green. BUT if you live in Texas or other states where coal is used to generate electricity, then your electricity is NOT "green"; your house and your EV is running off COAL and that will not change any time soon since there are not enough renewables to feed the energy needs of the US.
We moved into a condo a year ago and lucked out in that all the units have individual heat pumps for climate control. We are not at the mercy of the building when we want to turn on the heat or AC and because the unit is also well insulated, our utility bills are 1/4 of our old house.
"It means that heat pumps aren’t being subjected to the same kind of pointless culture war that has hindered the implementation of ... induction stoves."
Not pointless for those of us who like good food and care about cooking, and don't want the federal government micromanaging how we cook our food. Note that the culture war about gas stoves only began when a commissioner of the Consumer Public Safety Commission stated in an interview that he wished to ban gas stoves altogether. Also note that this madness was based on a spate of very sketchy, speculative studies that have now largely been debunked. This was far from "pointless" outrage, and isn't something that conservatives fabricated out of the blue.
As for heat pumps, they sound great in terms of efficiency gain. The big concern, as with all purely electric appliances, is what happens when the power goes out. I used to live in a mountainous, rural-ish, very snowy region of California. Winter power outages were a frequent occurrence, often for days at a time. Much more frequent than gas outages.
On the positive side: I've heard a lot of groaning from degrowther types about how air conditioning is bad and evil and should be heavily restricted. Perhaps wider adoption of heat pumps could counteract the outdoor warming effect of summer AC by dumping out colder air in the winter?
If they work, they are fine and super savers to boot. More than half of my friends experience issues of different sorts. Still a half baked tech, i guess. Needs further developement.
I was told by some HVAC pros that in Minnesota, I cannot have a heat pump installed without a backup source of heat, due to the heat pumps not working in temps below -13.
No discussion of heat pumps would be complete without a discussion of the refrigerants used in heat pumps. These refrigerants can cause serious environmental problems if/when released into the atmosphere, as is often the case [in particular in poorly regulated places like China, India, Africa and South America]. The mass deployment of heat pumps/air conditioners in those places is an environmental disaster already in process.