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Electric heat pumps + insulating to PassivHaus standards is very much competitive with carbon based fuels in colder climates. The operating cost is very low. Bu

Electric heat pumps + insulating to PassivHaus standards is very much competitive with carbon based fuels in colder climates. The operating cost is very low. But the up front investment can be steep.

danans 8y ago
The insanity is that tons of houses have central air conditioning systems installed without a thought, and those are just heat pumps that can only be run one direction, for cooling. The problem is that heat pump based heaters and cooling devices are still produced, marketed, and priced for the green and well off crowd, not the general public. In the general public has no concept that the same technology they use for cooling could be used to heat their homes. So far the manufacturers of heat pumps seem content with their well-off niche, and don't seem interested in scaling production so that the technology is available to regular folks. Perhaps the margins on heat pumps aren't as good and they don't want to cannibalize their existing businesses selling natural gas powered heating systems, which they probably manufacture for a song (recall how Carrier ended up moving their home furnace production to Mexico anyway despite the political show that was made of them supposedly staying in Indiana) In other parts of the world many split heat pump systems are much cheaper.
- Scoundreller 8y ago
  Or an air conditioner along with a separate pool heater. Or a fridge/freezer that dumps out heat indoors during A/C season, and/or a hot water heater that isn’t combined with the refrigeration system. A single heat pump could run it all: fridge, freezer, pool, HVAC and hot water. Maybe even a pre-heat element on a stove top.
  - sbierwagen 8y ago
    >Maybe even a pre-heat element on a stove top. Going a little far there. The preheat loop would have to survive regular heating element temperatures, and most common refrigerants decompose above 500C.
    - Scoundreller 8y ago
      More like a keep-warm element on the stove top. Maybe it’s too close to the heating elements. Dunno. Would probably be fine for an inductive range.
    - sokoloff 8y ago
      Stovetop elements get over 900* F? That doesn’t seem intuitively right to me.
      - sbierwagen 8y ago
        Both electric and infrared stovetops can get hot enough to glow red, which means they have to be at least 550C: https://en.wikipedia.org/wiki/Red_heat https://en.wikipedia.org/wiki/Red_heat
- philipkglass 8y ago
  The problem is that heat pump based heaters and cooling devices are still produced, marketed, and priced for the green and well off crowd, not the general public. When I was growing up I lived in a suburban American house that was built in 1982 and had a heat pump. It was a middle class suburb and none of the adults were environmental activists. Every house in the neighborhood had a heat pump. I thought this was totally normal. With hindsight, I see that there was significantly more American concern about energy efficiency in the late 1970s and early 1980s than in the early 1990s, probably due to resumption of relatively low oil prices in the mid 1980s. It's sad that the attention to efficiency did not continue after the immediate crisis had passed.
  - bluGill 8y ago
    The concern for energy efficiency died in the mid 1980s because there were a lot of badly done improvements. Many houses were insulated better - with a foam that had hazardous off gas problems. New homes were often insulated well and rotted away because the insulation trapped moisture. Heat pumps sounded good, but were useless on the cold days and so people paid huge power bills in January for electric heat. None of the above problems are inherent in energy efficiency, but they did give the whole field a bad name.
    - _delirium 8y ago
      In the UK, electric heating also got a reputation for not really having working temperature control. Because it was expensive to heat using day-rate electricity, most UK homes with electric heating have some kind of heat-storage system that charges at night at the "Economy 7" rate. The apartment I lived in (built 1984) heated up something like 100 lbs (60 kg) of ceramic blocks, for example. You could sort-of regulate how fast this heat dissipated during the day by opening and closing a vent, but in practice the biggest usable knob was choosing how much to charge overnight. That meant you had to predict before going to bed how much heat you'd want the next day! One strategy is to go very warm and then open your windows to cool back down if you overshot. Another strategy is to somewhat under-heat and then have a portable electric space heater to add extra heat in your immediate vicinity (though this is a common source of fires).
Gibbon1 8y ago
> PassivHaus standards The PassivHaus stuff is a really good example of the derangement you get when people try to optimize for only one metric. PassivHaus's are expensive, mandate the use of petroleum based insulation (you're living in a plastic burger box), prone to water intrusion mold and sick building syndrome and the supposed efficiency gains disappear when you open a window. Telling is the PassivHaus nutters response to builders wanting to use solar panels to build houses with low external energy needs. AKA why spend $100k on insulation when you can put a $20k worth of solar on the roof and a ground sourced heat pump. PassivHaus response is to get regulators to ban that option.
- dangravell 8y ago
  Even a cursory investigation or education of passivhaus concepts would show this to be nonsense. Passivhaus is not focused on one metric. To achieve passivhaus there are many metrics measured. Energy use, overheating, air quality, thermal bridging... The list goes on. I'm not sure what one metric you're referring to. Passivhaus does not mandate plastic based insulation. Many are built with cellulose, wood fibre,straw bales... They are not in any way more prone to water intrusion any more than any other building. They are far less likely to suffer sick building syndrome because ventilation standards are far higher than for 'normal' houses. You can open the windows if you want. Sure, if you do it in -10 temperatures you lose some heat. Passivhaus 'nutters' are generally apathetic about PV. You don't need PV ; simplicity is part of the point. The marginal cost on insulation is generally pretty low. The difficult but it's getting builders diligent enough for the challenge. Hope that helps to encourage you to continue researching the subject.
  - vkou 8y ago
    > Passivhaus does not mandate plastic based insulation... wood fibre,straw bales... So, I presume that in the case of a fire, they go up like a match?
    - jgamman 8y ago
      i think you're confusing a haystack with a compressed straw bale - IIRC the fire resistance of a compressed straw bale is excellent. it singes on the outside but it's v difficult to burn through.
chongli 8y ago
I really don't like the idea of PassivHaus. I don't want to live in a hermetically sealed pod. I like a house with a very high rate of fresh air exchange with the outdoors. There are so many sources of odor in a house that need to be cleared out, not to mention CO2. Yeah, you could have some sophisticated ventilation with a heat exchanger but that's one more piece of equipment to maintain and if it fails without you noticing it then the air quality could decline very rapidly.
- KozmoNau7 8y ago
  The current recommendation here is to air out for 5-10 minutes, 3 times a day. Not just one window open, but full airing out with as many open windows and doors as possible. It's a good habit to get into, no matter how old and drafty or new and tightly sealed your house is.
- jessaustin 8y ago
  These objections make sense, and in the right climate open windows will meet most of your comfort needs. In other climates controlling the movement of air is the only way to control the energy needed to heat and cool.
- Tharkun 8y ago
  I think you misunderstand PassivHaus. Ventilation and air quality are a big part of it. If there are smells or high CO2 levels, it's not up to the standard.

Electric heat pumps + insulating to PassivHaus standards is very much competitive with carbon based fuels in colder climates. The operating cost is very low. But the up front investment can be steep.

danans 8y ago

The insanity is that tons of houses have central air conditioning systems installed without a thought, and those are just heat pumps that can only be run one direction, for cooling. The problem is that heat pump based heaters and cooling devices are still produced, marketed, and priced for the green and well off crowd, not the general public. In the general public has no concept that the same technology they use for cooling could be used to heat their homes. So far the manufacturers of heat pumps seem content with their well-off niche, and don't seem interested in scaling production so that the technology is available to regular folks. Perhaps the margins on heat pumps aren't as good and they don't want to cannibalize their existing businesses selling natural gas powered heating systems, which they probably manufacture for a song (recall how Carrier ended up moving their home furnace production to Mexico anyway despite the political show that was made of them supposedly staying in Indiana) In other parts of the world many split heat pump systems are much cheaper.

Scoundreller 8y ago
Or an air conditioner along with a separate pool heater. Or a fridge/freezer that dumps out heat indoors during A/C season, and/or a hot water heater that isn’t combined with the refrigeration system. A single heat pump could run it all: fridge, freezer, pool, HVAC and hot water. Maybe even a pre-heat element on a stove top.
- sbierwagen 8y ago
  >Maybe even a pre-heat element on a stove top. Going a little far there. The preheat loop would have to survive regular heating element temperatures, and most common refrigerants decompose above 500C.
  - Scoundreller 8y ago
    More like a keep-warm element on the stove top. Maybe it’s too close to the heating elements. Dunno. Would probably be fine for an inductive range.
  - sokoloff 8y ago
    Stovetop elements get over 900* F? That doesn’t seem intuitively right to me.
    - sbierwagen 8y ago
      Both electric and infrared stovetops can get hot enough to glow red, which means they have to be at least 550C: https://en.wikipedia.org/wiki/Red_heat https://en.wikipedia.org/wiki/Red_heat
philipkglass 8y ago
The problem is that heat pump based heaters and cooling devices are still produced, marketed, and priced for the green and well off crowd, not the general public. When I was growing up I lived in a suburban American house that was built in 1982 and had a heat pump. It was a middle class suburb and none of the adults were environmental activists. Every house in the neighborhood had a heat pump. I thought this was totally normal. With hindsight, I see that there was significantly more American concern about energy efficiency in the late 1970s and early 1980s than in the early 1990s, probably due to resumption of relatively low oil prices in the mid 1980s. It's sad that the attention to efficiency did not continue after the immediate crisis had passed.
- bluGill 8y ago
  The concern for energy efficiency died in the mid 1980s because there were a lot of badly done improvements. Many houses were insulated better - with a foam that had hazardous off gas problems. New homes were often insulated well and rotted away because the insulation trapped moisture. Heat pumps sounded good, but were useless on the cold days and so people paid huge power bills in January for electric heat. None of the above problems are inherent in energy efficiency, but they did give the whole field a bad name.
  - _delirium 8y ago
    In the UK, electric heating also got a reputation for not really having working temperature control. Because it was expensive to heat using day-rate electricity, most UK homes with electric heating have some kind of heat-storage system that charges at night at the "Economy 7" rate. The apartment I lived in (built 1984) heated up something like 100 lbs (60 kg) of ceramic blocks, for example. You could sort-of regulate how fast this heat dissipated during the day by opening and closing a vent, but in practice the biggest usable knob was choosing how much to charge overnight. That meant you had to predict before going to bed how much heat you'd want the next day! One strategy is to go very warm and then open your windows to cool back down if you overshot. Another strategy is to somewhat under-heat and then have a portable electric space heater to add extra heat in your immediate vicinity (though this is a common source of fires).

Gibbon1 8y ago

> PassivHaus standards The PassivHaus stuff is a really good example of the derangement you get when people try to optimize for only one metric. PassivHaus's are expensive, mandate the use of petroleum based insulation (you're living in a plastic burger box), prone to water intrusion mold and sick building syndrome and the supposed efficiency gains disappear when you open a window. Telling is the PassivHaus nutters response to builders wanting to use solar panels to build houses with low external energy needs. AKA why spend $100k on insulation when you can put a $20k worth of solar on the roof and a ground sourced heat pump. PassivHaus response is to get regulators to ban that option.

dangravell 8y ago
Even a cursory investigation or education of passivhaus concepts would show this to be nonsense. Passivhaus is not focused on one metric. To achieve passivhaus there are many metrics measured. Energy use, overheating, air quality, thermal bridging... The list goes on. I'm not sure what one metric you're referring to. Passivhaus does not mandate plastic based insulation. Many are built with cellulose, wood fibre,straw bales... They are not in any way more prone to water intrusion any more than any other building. They are far less likely to suffer sick building syndrome because ventilation standards are far higher than for 'normal' houses. You can open the windows if you want. Sure, if you do it in -10 temperatures you lose some heat. Passivhaus 'nutters' are generally apathetic about PV. You don't need PV ; simplicity is part of the point. The marginal cost on insulation is generally pretty low. The difficult but it's getting builders diligent enough for the challenge. Hope that helps to encourage you to continue researching the subject.
- vkou 8y ago
  > Passivhaus does not mandate plastic based insulation... wood fibre,straw bales... So, I presume that in the case of a fire, they go up like a match?
  - jgamman 8y ago
    i think you're confusing a haystack with a compressed straw bale - IIRC the fire resistance of a compressed straw bale is excellent. it singes on the outside but it's v difficult to burn through.

chongli 8y ago

I really don't like the idea of PassivHaus. I don't want to live in a hermetically sealed pod. I like a house with a very high rate of fresh air exchange with the outdoors. There are so many sources of odor in a house that need to be cleared out, not to mention CO2. Yeah, you could have some sophisticated ventilation with a heat exchanger but that's one more piece of equipment to maintain and if it fails without you noticing it then the air quality could decline very rapidly.

KozmoNau7 8y ago
The current recommendation here is to air out for 5-10 minutes, 3 times a day. Not just one window open, but full airing out with as many open windows and doors as possible. It's a good habit to get into, no matter how old and drafty or new and tightly sealed your house is.
jessaustin 8y ago
These objections make sense, and in the right climate open windows will meet most of your comfort needs. In other climates controlling the movement of air is the only way to control the energy needed to heat and cool.
Tharkun 8y ago
I think you misunderstand PassivHaus. Ventilation and air quality are a big part of it. If there are smells or high CO2 levels, it's not up to the standard.