Believe me, it frequently gets below freezing in Minneapolis and my cold-climate ASHP works very well. My heat pump also has a decent warranty so that makes me sleep better. However, I respect your opinion about the potential costs of heat pump repair given your experience in the industry. People should look carefully at the pros and cons of buying a heat pump for their particular situation. They may not be for everyone. And for goodness sakes, don’t rely solely upon a heat pump if you live in an area that gets brutally cold.
Cost wise I’m not sure since how our system compares to heating that relies only on a forced-air gas furnace since when we bought our house we put in the ASHP almost immediately. What we have now is ASHP that works with a gas furnace. We set it up so that when the outside temperature goes below +15 degrees Fahrenheit only the gas furnace operates. Above +15, the gas furnace heats the house up initially and then the ASHP takes over. Over +30, the heat is supplied mostly by the ASHP. I can give you some numbers for last winter though.
For 2 days I turned the furnace off when the outside temperature averaged +32. On those 2 days the ASHP consumed about 27 kWh a day so at $0.12 per kWh, it cost $3.24 to heat the house.
When I switched the furnace back on, I found that over a period of 7 days when the outside temperature averaged +32, the ASHP averaged 16 kWh/day and the furnace averaged 5.4 therms a day. At $0.12/ kWh and $0.55/therm, the total cost per day averaged $2.34.
Last winter was very warm. The coldest day only went down to -8 degrees Fahrenheit. Only the gas furnace ran on that day. It used 6.2 therms of gas which cost $3.41.
So I don’t think using an ASHP added a lot to the cost of heating our house last winter, but it would have cost less to heat our house solely with our 95% efficient gas furnace. Prices for natural gas though have been volatile lately. I’m glad we weren’t paying over $1.00 per therm like when NG prices peaked in 2022. In comparison our electric rates have hardly budged at $0.12/kWh.
I used to fix heat pumps for a living. Yes, they are nice in areas where the outside temp never drops below freezing.
But you have to balance your electricity savings with the cost of repairs. When that compressor goes out, you're looking at a couple of thousand bucks to fix it.
And they don't go out when it's convenient for YOU. Equipment tends to fail when it has to work the hardest.
So, you'll be without heat when you need it the most.
Timely comment. My split unit works for cooling, but is down when I want heat. Fortunately, we use our wood stove all the time, but I do like using the split unit for heat when it's too cool for comfort, but not cold enough to feel like building a fire. Turns out the repair calls for either a mother board or a stuck valve that switches from cool to heat. So expensive to repair that I've been holding off...
Our experience with an air-source heat pump for our Minneapolis home has been a positive one. I am surprised that some people prefer natural gas over an ASHP when it comes to comfort. We find the temperature in our house to be much more consistent with our variable speed ASHP than with our NG furnace. Perhaps people dissatisfied with their ASHPs have the more economical single or 2-stage units. Our unit is also very quiet. We set our lock-out at +15 degrees Fahrenheit and pair it with a NG furnace, so it is economical. Many homeowners in Minnesota who convert to cold climate ASHPs use NG furnaces to supplement the ASHP. The people here who benefit the most economically from switching to ASHPs are those who switch from resistance electricity or propane.
Yes, that certainly makes the house more comfortable regardless of the heat source. There are so many variables that can affect the success or failure of a particular heating/cooling system. One person’s good experience with an ASHP doesn’t mean somebody else’s bad experience isn’t valid I guess.
And on efficiency, heat pump advocates don’t usually highlight the cost difference of energy. It depends on location but a 1MMBTUS of gas is often cheaper than 1MMbtus of electricity at night.. As the article points out, to get electricity in winter you have to run that gas through a power plant and transmission lines first, and that adds costs. With gas, you skip those costs and make the heat directly at home.
Wonderfully explained! Just the facts man! A country dead set on self destruction at the claim of saving something unchangeable by humans! Climate disinformation is more than it seems, a grander ploy imo towards a worldly central command…..
The incompetence of elected and unelected policy makers is remarkable. The apathy of the general public is not far behind. Both very unfortunate for our continuing flourishing as a nation.
Thank you for a good read Spudster. I'm writing from the UK and my slant is a little different, and much less colourful than yours and Robert Bryce's. Maybe the tendency to portray heat pumps and EVs is vivid colour is down to the fact that we humans simply don't like being told what to do, and it's hard to see how either are ultimately going to achieve deep market penetration without coercion.
The take-up of heat pumps is particularly low in the UK, at around 1% of homes, considerably less than the figures I've seen for the US. A large number of UK homes, still very much inhabited, were clearly designed around the availability of cheap coal, with similar thermal insulation to that of a paper bag, and originally, a fireplace in most rooms, including small bedrooms. My wife and I lived in such a house for over 40 years, improving the situation somewhat.
On top of this, from the 1970s, people in the UK had the luxury of North Sea natural gas, and the gas furnace (inappropriately referred to a "boilers" despite them containing a number of systems to prevent boiling) became widespread, operating at high flow temperatures (water is used to transfer heat here rather than air).
To make a heat pump work well in older properties involves much more than swapping out the furnace for a more expensive heat pump, with additional insulation and larger heat emitters, typically radiators (which are actually convectors). As the combination or "combi" furnace is popular, which provides instantaneous hot water, changing to a heat pump may also involve fitting a large hot water storage cylinder in properties that as you say, are often quite small (real-estate agents here use the term "deceptively spacious", meaning it's small and I'm trying to deceive you). Little wonder then that heat pump adoption is sluggish.
The Nordic countries, lacking such wealth of fuel many years ago, sensibly insulated their homes as a matter of course, and I think it is this factor, as much as cheap electricity, that accounts for the widespread use of heat pumps in these cold places. The citizens of these countries, certainly the ones I've met, are not notably well-disposed to suffering, so I think it fair to assume that heat pumps can work adequately there, if perhaps not always optimally.
My position is one of privilege and good fortune, having been able to build a well-insulated bungalow from scratch. As we're not on the gas grid, we have an air source heat pump with underfloor heating (UFH, with water at low temperature for heat transfer), a near-perfect match. This gives a radiator area a little less than the whole internal floor area. Admittedly the winters here don't tend to be very cold, but we're toasty, and warming with UFH is exquisite. As a bonus, the machine is quiet. An oversight of mine is not considering cooling, which is why ducted air systems are popular in the US. There's relatively little need for it most of the time in the UK until of course, we get overwhelmed by the climate crisis. To quote Samuel Taylor Coleridge, writing in 1826, "Summer has set in with its usual severity".
Thank you Spudster: a little bit more, from a young Finnish lady living in north Wales, commenting on the coldness of British homes: "People say to me 'but isn't it cold in Finland?', to which I reply 'Outside, yes'".
Great post. My only nit pick is that I think the distinction should always be made between air source and ground source heat pumps. I am on my fifth ground source system (none wore out, we just built a lot of buildings!) and they are fantastic. My house is forced air ground source and my shops are in-floor. We always over-insulate and you have to make sure you use a big enough ground loop. I had an air source heat pump for space heating a small apartment (about 650 sq/ft) and it worked well, even in southern Ontario where it can get very cold. I'm not sure if it had electric supplementary however. I didn't know that little trick until reading stuff here on Substack. Good info. Thanks.
Cost wise they aren't they great in the cool. The promoters claim 400% efficiency. So I took their never to be achieved number and ran with it. Figuring the cost per btuh based on my kwh rate vs my cost per btuh based on my cost per therm, my 95% efficient gas furnace is still cheaper to operate than a 400% efficient heat pump. 🤷
Regarding comfort, I didn't see defrost mode mentioned. When my heat pump goes into defrost mode (7 minutes every hour), the air coming out of the register does not feel comfortable to me. I keep my thermostat at 74 so that might explain some of it. I have had heat pumps for 50 years. My last two have been top of the line. They work great in the summer. In the winter they are quite comfortable down to 40. Below 30 I don't find them comfortable. I live in Virginia which should be the ideal climate for heat pumps.
Just one more report from the 45th parallel, in Michigan. Half my house is gas and half is heat pumps. Both the gas costs and the electric costs go up a lot in the winter. But I disagree vehemently (and atypically) with Robert Bryce. My heat pump heads are quiet in the house and the heat exchangers outside are much quieter than a standard AC heat exchanger. For winter conditions, I have a 40 W (!) ceramic heater at the window near which I sit. I do have supplemental, portable, resistance heaters for use under the coldest conditions. Ran them very little last winter, as it was a warm one.
In addition, I struggled for decades of having vented forced air systems trying to achieve temperature balance across spaces and stories. Having separate control of each heat-pump head is a delight.
This is the thing about opposition to having things shoved down your throat, which I too oppose. The opposing arguments get so ridiculous that a sensible person is found holding their nose.
Thanks - I always appreciate a balanced view. I have a Mitzubishi split unit just for the family rm and the master bdrm. I do enjoy the air conditioning, especially to sleep better on hot nights. But for heat, our unit isn't much good below 40 deg F.
TANSTAFL - There Ain't no Such Thing as a Free Lunch - modern units that work in cold weather rely, as you say, on electric resistance heat, which is very expensive.
Ha - I got that acronym from an actual company by that name. I used to buy special hi-temp wire for commercial oven, grill, and fryer repair from them. Their wire was very expensive, and when I commented on it, they explained why they named their company TANSTAFL.
i tore out my ground source geothermal system after years of frustration. it worked, mostly, but the repairs were endless. i had 2 units, and one of them required replacing its control panel several times. [a lemon?] i saved significant money on energy, but then spent all the savings on maintenance/repairs. my system was open loop, fyi, but my contractor said his experience with closed loop systems wasn't very different. i now have a propane furnace with a buried 1000 gal tank which also goes to my whole-house generator and my stovetop. and i have a wood stove.
I am living this. Built a new “net zero” home in NH with a heat pump. Worst idea ever. Now building a new home with outdoor wood boiler. There’s something about waking up in a 55 degree house and knowing it is not going to get any warmer. It’s even worse when they champion using a heat pump water heater INSIDE A HEAT PUMP HEATED HOUSE. That’s a compounding effect - let’s use air to transfer that heat. SMH
Just wondering, how important is air humudity for the performance of heat pumps? I live in Norway and I can’t recall hearing any of my aquaintances complaining about their heat pumps, like, ever. We are pretty far north in Noway and air humudity is very low in the winter, both indoors and outdoors, could that be it?
Yup, higher humidity definitely has a negative impact on performance. Good point.
High humidity can cause moisture in the air to freeze on the outdoor unit's coils. This reduces the heat pump's efficiency by impeding heat transfer + to counter this, the heat pump periodically enters a defrost cycle to melt the frost. Frequent defrost cycles consumes additional energy and disrupts the heating process
Thanks for replying. One minor thing in the article just to get the record straight: cheap electricity in the winter months is a thing of the past in Norway, thanks to German energy policy.
Believe me, it frequently gets below freezing in Minneapolis and my cold-climate ASHP works very well. My heat pump also has a decent warranty so that makes me sleep better. However, I respect your opinion about the potential costs of heat pump repair given your experience in the industry. People should look carefully at the pros and cons of buying a heat pump for their particular situation. They may not be for everyone. And for goodness sakes, don’t rely solely upon a heat pump if you live in an area that gets brutally cold.
Well said! And really appreciate the respectful dialogue 🙏🏼
Thanks. Following your lead. We can disagree without being disagreeable.
That’s the dream. Easier said than done…
Isn't your electricity cost high during cold snaps?
Cost wise I’m not sure since how our system compares to heating that relies only on a forced-air gas furnace since when we bought our house we put in the ASHP almost immediately. What we have now is ASHP that works with a gas furnace. We set it up so that when the outside temperature goes below +15 degrees Fahrenheit only the gas furnace operates. Above +15, the gas furnace heats the house up initially and then the ASHP takes over. Over +30, the heat is supplied mostly by the ASHP. I can give you some numbers for last winter though.
For 2 days I turned the furnace off when the outside temperature averaged +32. On those 2 days the ASHP consumed about 27 kWh a day so at $0.12 per kWh, it cost $3.24 to heat the house.
When I switched the furnace back on, I found that over a period of 7 days when the outside temperature averaged +32, the ASHP averaged 16 kWh/day and the furnace averaged 5.4 therms a day. At $0.12/ kWh and $0.55/therm, the total cost per day averaged $2.34.
Last winter was very warm. The coldest day only went down to -8 degrees Fahrenheit. Only the gas furnace ran on that day. It used 6.2 therms of gas which cost $3.41.
So I don’t think using an ASHP added a lot to the cost of heating our house last winter, but it would have cost less to heat our house solely with our 95% efficient gas furnace. Prices for natural gas though have been volatile lately. I’m glad we weren’t paying over $1.00 per therm like when NG prices peaked in 2022. In comparison our electric rates have hardly budged at $0.12/kWh.
I used to fix heat pumps for a living. Yes, they are nice in areas where the outside temp never drops below freezing.
But you have to balance your electricity savings with the cost of repairs. When that compressor goes out, you're looking at a couple of thousand bucks to fix it.
And they don't go out when it's convenient for YOU. Equipment tends to fail when it has to work the hardest.
So, you'll be without heat when you need it the most.
Remember that.
Timely comment. My split unit works for cooling, but is down when I want heat. Fortunately, we use our wood stove all the time, but I do like using the split unit for heat when it's too cool for comfort, but not cold enough to feel like building a fire. Turns out the repair calls for either a mother board or a stuck valve that switches from cool to heat. So expensive to repair that I've been holding off...
Our experience with an air-source heat pump for our Minneapolis home has been a positive one. I am surprised that some people prefer natural gas over an ASHP when it comes to comfort. We find the temperature in our house to be much more consistent with our variable speed ASHP than with our NG furnace. Perhaps people dissatisfied with their ASHPs have the more economical single or 2-stage units. Our unit is also very quiet. We set our lock-out at +15 degrees Fahrenheit and pair it with a NG furnace, so it is economical. Many homeowners in Minnesota who convert to cold climate ASHPs use NG furnaces to supplement the ASHP. The people here who benefit the most economically from switching to ASHPs are those who switch from resistance electricity or propane.
Interesting color. I assume your home is well insulated?
Yes, that certainly makes the house more comfortable regardless of the heat source. There are so many variables that can affect the success or failure of a particular heating/cooling system. One person’s good experience with an ASHP doesn’t mean somebody else’s bad experience isn’t valid I guess.
Yeah fair enough, that’s a good way to put it
So many different homes, technologies, installation qualities, etc etc
And on efficiency, heat pump advocates don’t usually highlight the cost difference of energy. It depends on location but a 1MMBTUS of gas is often cheaper than 1MMbtus of electricity at night.. As the article points out, to get electricity in winter you have to run that gas through a power plant and transmission lines first, and that adds costs. With gas, you skip those costs and make the heat directly at home.
Wonderfully explained! Just the facts man! A country dead set on self destruction at the claim of saving something unchangeable by humans! Climate disinformation is more than it seems, a grander ploy imo towards a worldly central command…..
Thank you!
Whether that’s the plan or not, that’s where things will inevitably go at this rate unfortunately…
The incompetence of elected and unelected policy makers is remarkable. The apathy of the general public is not far behind. Both very unfortunate for our continuing flourishing as a nation.
Yup, agree. Scary stuff
Thank you for a good read Spudster. I'm writing from the UK and my slant is a little different, and much less colourful than yours and Robert Bryce's. Maybe the tendency to portray heat pumps and EVs is vivid colour is down to the fact that we humans simply don't like being told what to do, and it's hard to see how either are ultimately going to achieve deep market penetration without coercion.
The take-up of heat pumps is particularly low in the UK, at around 1% of homes, considerably less than the figures I've seen for the US. A large number of UK homes, still very much inhabited, were clearly designed around the availability of cheap coal, with similar thermal insulation to that of a paper bag, and originally, a fireplace in most rooms, including small bedrooms. My wife and I lived in such a house for over 40 years, improving the situation somewhat.
On top of this, from the 1970s, people in the UK had the luxury of North Sea natural gas, and the gas furnace (inappropriately referred to a "boilers" despite them containing a number of systems to prevent boiling) became widespread, operating at high flow temperatures (water is used to transfer heat here rather than air).
To make a heat pump work well in older properties involves much more than swapping out the furnace for a more expensive heat pump, with additional insulation and larger heat emitters, typically radiators (which are actually convectors). As the combination or "combi" furnace is popular, which provides instantaneous hot water, changing to a heat pump may also involve fitting a large hot water storage cylinder in properties that as you say, are often quite small (real-estate agents here use the term "deceptively spacious", meaning it's small and I'm trying to deceive you). Little wonder then that heat pump adoption is sluggish.
The Nordic countries, lacking such wealth of fuel many years ago, sensibly insulated their homes as a matter of course, and I think it is this factor, as much as cheap electricity, that accounts for the widespread use of heat pumps in these cold places. The citizens of these countries, certainly the ones I've met, are not notably well-disposed to suffering, so I think it fair to assume that heat pumps can work adequately there, if perhaps not always optimally.
My position is one of privilege and good fortune, having been able to build a well-insulated bungalow from scratch. As we're not on the gas grid, we have an air source heat pump with underfloor heating (UFH, with water at low temperature for heat transfer), a near-perfect match. This gives a radiator area a little less than the whole internal floor area. Admittedly the winters here don't tend to be very cold, but we're toasty, and warming with UFH is exquisite. As a bonus, the machine is quiet. An oversight of mine is not considering cooling, which is why ducted air systems are popular in the US. There's relatively little need for it most of the time in the UK until of course, we get overwhelmed by the climate crisis. To quote Samuel Taylor Coleridge, writing in 1826, "Summer has set in with its usual severity".
Excellent color, thanks for providing. I think deep market penetration is possible, just on a pretty long timescale
Thank you Spudster: a little bit more, from a young Finnish lady living in north Wales, commenting on the coldness of British homes: "People say to me 'but isn't it cold in Finland?', to which I reply 'Outside, yes'".
Great post. My only nit pick is that I think the distinction should always be made between air source and ground source heat pumps. I am on my fifth ground source system (none wore out, we just built a lot of buildings!) and they are fantastic. My house is forced air ground source and my shops are in-floor. We always over-insulate and you have to make sure you use a big enough ground loop. I had an air source heat pump for space heating a small apartment (about 650 sq/ft) and it worked well, even in southern Ontario where it can get very cold. I'm not sure if it had electric supplementary however. I didn't know that little trick until reading stuff here on Substack. Good info. Thanks.
Definitely a fair point re distinguishing between ground vs air. No problem!
Cost wise they aren't they great in the cool. The promoters claim 400% efficiency. So I took their never to be achieved number and ran with it. Figuring the cost per btuh based on my kwh rate vs my cost per btuh based on my cost per therm, my 95% efficient gas furnace is still cheaper to operate than a 400% efficient heat pump. 🤷
🤷🏻♂️ indeed
The beauty is my gas furnace costs the same per btuh to operate at 50F or -5F, heat pump not so much.
Great point
Regarding comfort, I didn't see defrost mode mentioned. When my heat pump goes into defrost mode (7 minutes every hour), the air coming out of the register does not feel comfortable to me. I keep my thermostat at 74 so that might explain some of it. I have had heat pumps for 50 years. My last two have been top of the line. They work great in the summer. In the winter they are quite comfortable down to 40. Below 30 I don't find them comfortable. I live in Virginia which should be the ideal climate for heat pumps.
All good points
Just one more report from the 45th parallel, in Michigan. Half my house is gas and half is heat pumps. Both the gas costs and the electric costs go up a lot in the winter. But I disagree vehemently (and atypically) with Robert Bryce. My heat pump heads are quiet in the house and the heat exchangers outside are much quieter than a standard AC heat exchanger. For winter conditions, I have a 40 W (!) ceramic heater at the window near which I sit. I do have supplemental, portable, resistance heaters for use under the coldest conditions. Ran them very little last winter, as it was a warm one.
In addition, I struggled for decades of having vented forced air systems trying to achieve temperature balance across spaces and stories. Having separate control of each heat-pump head is a delight.
This is the thing about opposition to having things shoved down your throat, which I too oppose. The opposing arguments get so ridiculous that a sensible person is found holding their nose.
Thanks for the color!
Very good post! By the way, my long time nickname is Spud.
Brothers!
Thanks - I always appreciate a balanced view. I have a Mitzubishi split unit just for the family rm and the master bdrm. I do enjoy the air conditioning, especially to sleep better on hot nights. But for heat, our unit isn't much good below 40 deg F.
TANSTAFL - There Ain't no Such Thing as a Free Lunch - modern units that work in cold weather rely, as you say, on electric resistance heat, which is very expensive.
TANSTAFL - I’ll remember there one!
Ha - I got that acronym from an actual company by that name. I used to buy special hi-temp wire for commercial oven, grill, and fryer repair from them. Their wire was very expensive, and when I commented on it, they explained why they named their company TANSTAFL.
I laughed, and never forgot it.
That is amazing 😆
i tore out my ground source geothermal system after years of frustration. it worked, mostly, but the repairs were endless. i had 2 units, and one of them required replacing its control panel several times. [a lemon?] i saved significant money on energy, but then spent all the savings on maintenance/repairs. my system was open loop, fyi, but my contractor said his experience with closed loop systems wasn't very different. i now have a propane furnace with a buried 1000 gal tank which also goes to my whole-house generator and my stovetop. and i have a wood stove.
Interesting! Hm yeah, I’ve heard similar stories re maintenance issues
i also now have 2 central air units. i declined getting heat pumps instead - i really want to avoid any compexity.
I am living this. Built a new “net zero” home in NH with a heat pump. Worst idea ever. Now building a new home with outdoor wood boiler. There’s something about waking up in a 55 degree house and knowing it is not going to get any warmer. It’s even worse when they champion using a heat pump water heater INSIDE A HEAT PUMP HEATED HOUSE. That’s a compounding effect - let’s use air to transfer that heat. SMH
My feet are cold just thinking about that
Just wondering, how important is air humudity for the performance of heat pumps? I live in Norway and I can’t recall hearing any of my aquaintances complaining about their heat pumps, like, ever. We are pretty far north in Noway and air humudity is very low in the winter, both indoors and outdoors, could that be it?
Yup, higher humidity definitely has a negative impact on performance. Good point.
High humidity can cause moisture in the air to freeze on the outdoor unit's coils. This reduces the heat pump's efficiency by impeding heat transfer + to counter this, the heat pump periodically enters a defrost cycle to melt the frost. Frequent defrost cycles consumes additional energy and disrupts the heating process
Thanks for replying. One minor thing in the article just to get the record straight: cheap electricity in the winter months is a thing of the past in Norway, thanks to German energy policy.
Of course, no problem! Ugh really? What a bummer.