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This persistent myth just needs to go away. People use heat pumps all over Scandinavia, including in the arctic circle. They are extremely popular there. They w

This persistent myth just needs to go away. People use heat pumps all over Scandinavia, including in the arctic circle. They are extremely popular there. They were early adopters of this technology there decades ago. There are two popular varieties: - Ground source heat pumps. Those work pretty much anywhere; just dig below the perma frost and you are good to go on the northern tip of Canada, Alaska, Norway, or wherever. Works great, ground temperatures tend to be very stable and it actually goes up the deeper you dig. - Air source heat pumps. The expensive ones still work okish at extreme temperatures like -25-ish degrees C. Which is a reason these are actually more popular than ground sources even in places (e.g. most of Scandinavia) that reliably get such temperatures each winter.

__MatrixMan__ 3y ago
I've been on zoom calls with two separate co-workers who are all bundled up because their heat pump can't handle the weather. It doesn't mean that the technology is inadequate in principle--probably their systems have some problem that competent HVAC installers know how to avoid. But its an unfortunate fact that there are places in the US where installers that recommend heat pumps can't be found for 100 miles. It doesn't really matter if I'm technically correct about the merits of the tech in principle--if I can't find somebody to fix my system and my pipes start exploding, I've still made the wrong decision. Also, heavy snows cause power outages in places where tree limbs fall on overhead lines. If gas outages happen... well I've never experienced one. Sure, if I lived in Norway I'd have a government that cares about updated infrastructure and I wouldn't have these problems, but since I don't, I do. Given my local constraints, a dual-fuel system sounds pretty great.
- jillesvangurp 3y ago
  Gas outages happened at a large scale in Texas when they were struggling with a bit of cold weather. When they needed it the most, it failed them. Coal plants also struggled. Both had challenges with supply of fuel and cooling water being disrupted. That kind of systemic infrastructure failures is on the rise in the US. There are all sorts of reasons why governance just isn't great in the US. But the reality indeed is that things are unlikely to improve on that front. Which are all good reasons why the market for domestic solar, batteries, and heat pumps is so hot right now. The US is no exception to this.
  - deleted 3y ago
    [deleted]
- nawitus 3y ago
  Properly designed heat pump system includes backup for the coldest days - usually direct electric heating. Most houses in Finland have a (decent) fireplace for heating in case of an electric outage.
- sokoloff 3y ago
  > heavy snows cause power outages in places where tree limbs fall on overhead lines. If gas outages happen... well I've never experienced one. If I lose power, my gas boiler does me no good. A gas boiler will use pumps (and likely a power vent). A gas furnace will use a fan and a power vent.
  - nightski 3y ago
    It's a lot easier to keep a gas furnace running on a generator for an extended period of time than a heat pump.
- Tor3 3y ago
  There are power outages in Norway too - though there are typically years between incidents, and years and years between incidents lasting a day instead of hours (with the exception of certain avalanche-prone areas where this happens much more often than people would like). So my home has a backup system - as do most houses. And that's a wood heater. But my house is so well insulated that it takes a day even in the coldest of winter before I actually need to use it if this happens. Newer houses are also quite much better than mine in this respect.
gambiting 3y ago
Air source heat pumps are super popular in Poland too, this winter it was about -20C for couple weeks straight and not had any problems, toasty house without any issues. The key is that the heat pump exchanger really needs to be huge(ours is taller than a person) to get the heat out of the air.
rayiner 3y ago
The myth exists because the US is probably 10-20 years behind Europe and China in terms of HVAC and insulation technology. I recently had some reasonably high efficiency heat pumps installed at my house, and I’ve been very unhappy with the low temperature performance. It doesn’t even get very cold here—rarely below 5F (-15C) and a record low of -8F (-22C). The heat pumps I got (recommended by the well-regarded local HVAC company) operate at just 40% of rated capacity at 0F.[1] Meanwhile, Chinese and Japanese-made inverter driven heat pumps will happily go down to -5F at 100% of rated capacity, and -22F (-30C) at 80% of rated capacity. [1] You can of course get a much larger heat pump to compensate, but that leaves the unit way over-sized for cooling loads.
- nielsbot 3y ago
  Can't you get backup heating in addition to a heat pump for the coldest days?
  - lsaferite 3y ago
    I live in FL and we have a backup resistive heating element that kicks in as needed. Mostly only comes on a few days in the year or for short bursts when there's a cold snap that the heat pump can't keep up with.
    - rayiner 3y ago
      This is fine until everyone in your neighborhood has one and it causes a brown out. (Peak amperage for the heating strips on my heat pump are three times as high as for the heat pump itself at maximum cooling load.)
      - nielsbot 3y ago
        You can upgrade your home electrical service and the power company handles all that for you.
- simonblack 3y ago
  Sounds like the units you are describing don't have an efficient (read 'big enough') heat-exchanger which is why they aren't being effective in not-so-low temperatures. The temperature of the cold-side should not be below outside ambient temperatures if the heat exchanger coils are sufficient. In other words heat-energy should be going into cold side of the heat-pump (even at a low temperatures) at the same rate as it is coming out the hot-side at high temperatures. Reduce the heat in, and you will reduce the heat out.
simonblack 3y ago
Ditto Australia. We've been using 'reverse-cycle air-conditioners' for heating in Australia for decades. I'm puzzled as to why there is any debate at all on their use for heating. A heat-pump is far more efficient for obtaining heat than direct resistive heating using electricity. Many houses here use no other form of heating at all. And then at the press of a button, we get cooling in summer too. What's not to like? * I also have a heat-pump condensing clothes dryer. The overall heat thrown out into the room is extremely low. The hot-air comes out the hot-side of the heat-pump to dry the clothes. The warm-moist air then passes over the cold coils, condensing out the water from the clothes and returning the heat to the cold-side of the heat pump which then pushes that heat-energy out the hot-side, producing more hot air to complete the cycle. I've had this Miele heat-pump condensing dryer going strong since 2009 - 14 years.
- verve_rat 3y ago
  Yeah, as a Kiwi, watching all the debate happening here is just super weird. Meanwhile, I'm annoyed that heat pumps that dump the waste heat into the hot water cylinder aren't standard.
  - Maxion 3y ago
    It's just the Yanks that have subsidised natural gas in many states, and a messed up energy infrastructure that gives electricity prices in the same range as what we have in Europe while being at war.
    - pkaye 3y ago
      I was trying to find heat pump adoption rates for Europe and US. Seems like its still pretty low in Europe outside some northern countries. Germany is less than 2000/100000 people. https://www.theecoexperts.co.uk/heat-pumps/top-countries https://www.theecoexperts.co.uk/heat-pumps/top-countries Meanwhile this link says US has a 15% adoption rate across all income groups. That seems higher than I expected. https://energypost.eu/u-s-heat-pump-adoption-is-evenly-spread-across-rich-and-poor-surprised https://energypost.eu/u-s-heat-pump-adoption-is-evenly-sprea... Is there a better source on heat pump adoption rate in Europe and US?

__MatrixMan__ 3y ago

I've been on zoom calls with two separate co-workers who are all bundled up because their heat pump can't handle the weather. It doesn't mean that the technology is inadequate in principle--probably their systems have some problem that competent HVAC installers know how to avoid. But its an unfortunate fact that there are places in the US where installers that recommend heat pumps can't be found for 100 miles. It doesn't really matter if I'm technically correct about the merits of the tech in principle--if I can't find somebody to fix my system and my pipes start exploding, I've still made the wrong decision. Also, heavy snows cause power outages in places where tree limbs fall on overhead lines. If gas outages happen... well I've never experienced one. Sure, if I lived in Norway I'd have a government that cares about updated infrastructure and I wouldn't have these problems, but since I don't, I do. Given my local constraints, a dual-fuel system sounds pretty great.

jillesvangurp 3y ago
Gas outages happened at a large scale in Texas when they were struggling with a bit of cold weather. When they needed it the most, it failed them. Coal plants also struggled. Both had challenges with supply of fuel and cooling water being disrupted. That kind of systemic infrastructure failures is on the rise in the US. There are all sorts of reasons why governance just isn't great in the US. But the reality indeed is that things are unlikely to improve on that front. Which are all good reasons why the market for domestic solar, batteries, and heat pumps is so hot right now. The US is no exception to this.
- deleted 3y ago
  [deleted]
nawitus 3y ago
Properly designed heat pump system includes backup for the coldest days - usually direct electric heating. Most houses in Finland have a (decent) fireplace for heating in case of an electric outage.
sokoloff 3y ago
> heavy snows cause power outages in places where tree limbs fall on overhead lines. If gas outages happen... well I've never experienced one. If I lose power, my gas boiler does me no good. A gas boiler will use pumps (and likely a power vent). A gas furnace will use a fan and a power vent.
- nightski 3y ago
  It's a lot easier to keep a gas furnace running on a generator for an extended period of time than a heat pump.
Tor3 3y ago
There are power outages in Norway too - though there are typically years between incidents, and years and years between incidents lasting a day instead of hours (with the exception of certain avalanche-prone areas where this happens much more often than people would like). So my home has a backup system - as do most houses. And that's a wood heater. But my house is so well insulated that it takes a day even in the coldest of winter before I actually need to use it if this happens. Newer houses are also quite much better than mine in this respect.

gambiting 3y ago

Air source heat pumps are super popular in Poland too, this winter it was about -20C for couple weeks straight and not had any problems, toasty house without any issues. The key is that the heat pump exchanger really needs to be huge(ours is taller than a person) to get the heat out of the air.

rayiner 3y ago

The myth exists because the US is probably 10-20 years behind Europe and China in terms of HVAC and insulation technology. I recently had some reasonably high efficiency heat pumps installed at my house, and I’ve been very unhappy with the low temperature performance. It doesn’t even get very cold here—rarely below 5F (-15C) and a record low of -8F (-22C). The heat pumps I got (recommended by the well-regarded local HVAC company) operate at just 40% of rated capacity at 0F.[1] Meanwhile, Chinese and Japanese-made inverter driven heat pumps will happily go down to -5F at 100% of rated capacity, and -22F (-30C) at 80% of rated capacity. [1] You can of course get a much larger heat pump to compensate, but that leaves the unit way over-sized for cooling loads.

nielsbot 3y ago
Can't you get backup heating in addition to a heat pump for the coldest days?
- lsaferite 3y ago
  I live in FL and we have a backup resistive heating element that kicks in as needed. Mostly only comes on a few days in the year or for short bursts when there's a cold snap that the heat pump can't keep up with.
  - rayiner 3y ago
    This is fine until everyone in your neighborhood has one and it causes a brown out. (Peak amperage for the heating strips on my heat pump are three times as high as for the heat pump itself at maximum cooling load.)
    - nielsbot 3y ago
      You can upgrade your home electrical service and the power company handles all that for you.
simonblack 3y ago
Sounds like the units you are describing don't have an efficient (read 'big enough') heat-exchanger which is why they aren't being effective in not-so-low temperatures. The temperature of the cold-side should not be below outside ambient temperatures if the heat exchanger coils are sufficient. In other words heat-energy should be going into cold side of the heat-pump (even at a low temperatures) at the same rate as it is coming out the hot-side at high temperatures. Reduce the heat in, and you will reduce the heat out.

simonblack 3y ago

Ditto Australia. We've been using 'reverse-cycle air-conditioners' for heating in Australia for decades. I'm puzzled as to why there is any debate at all on their use for heating. A heat-pump is far more efficient for obtaining heat than direct resistive heating using electricity. Many houses here use no other form of heating at all. And then at the press of a button, we get cooling in summer too. What's not to like? * I also have a heat-pump condensing clothes dryer. The overall heat thrown out into the room is extremely low. The hot-air comes out the hot-side of the heat-pump to dry the clothes. The warm-moist air then passes over the cold coils, condensing out the water from the clothes and returning the heat to the cold-side of the heat pump which then pushes that heat-energy out the hot-side, producing more hot air to complete the cycle. I've had this Miele heat-pump condensing dryer going strong since 2009 - 14 years.

verve_rat 3y ago
Yeah, as a Kiwi, watching all the debate happening here is just super weird. Meanwhile, I'm annoyed that heat pumps that dump the waste heat into the hot water cylinder aren't standard.
- Maxion 3y ago
  It's just the Yanks that have subsidised natural gas in many states, and a messed up energy infrastructure that gives electricity prices in the same range as what we have in Europe while being at war.
  - pkaye 3y ago
    I was trying to find heat pump adoption rates for Europe and US. Seems like its still pretty low in Europe outside some northern countries. Germany is less than 2000/100000 people. https://www.theecoexperts.co.uk/heat-pumps/top-countries https://www.theecoexperts.co.uk/heat-pumps/top-countries Meanwhile this link says US has a 15% adoption rate across all income groups. That seems higher than I expected. https://energypost.eu/u-s-heat-pump-adoption-is-evenly-spread-across-rich-and-poor-surprised https://energypost.eu/u-s-heat-pump-adoption-is-evenly-sprea... Is there a better source on heat pump adoption rate in Europe and US?