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> Is there a global push to get everyone to switch to heat pumps. I mean, yes. They're much more energy efficient than the alternatives and will play a key pa

> Is there a global push to get everyone to switch to heat pumps. I mean, yes. They're much more energy efficient than the alternatives and will play a key part of removing our dependence on fossil fuels. > I understand that its for climate benefits but it feels very coordinated. That seems like a good thing?

nashashmi 4y ago
They are not more energy efficient than burning gas. Edit: since i am getting downvoted to oblivion, let me fight back here. I genuinely wished heat pumps would be more efficient and in theory they can be. I would love to not generate heat and just use the outside heat energy and compress it down into a smaller location. But compressing and decompressing is not an energy efficient task. It takes a lot of work. Mechanical inefficiencies are a huge energy consumption. Gas is simply burning fuel. Yes, we should save gas for rainy days. But I hate to say that it is more efficient and cheap. There is no comparison.
- pjerem 4y ago
  Yes they are. You get more heating from an heat pump running from electricity coming from gas plants than what you get by just burning the gas. Including losses on the grid.
  - nashashmi 4y ago
    I cannot imagine this in anyway. Heat pumps work like ACs do. They do compress a medium till it heats up, and then spread that heat around. And then they decompress until it cools down and dump that cold until outside heat brings up the temperature again. Those compressions and decompressions take up immense amounts of energy. They are less efficient than simply burning gas. On the flip side, could we not create electricity generation and heating from Natural gas?
    - baxuz 4y ago
      That's the whole point. For most modern systems you get >4x of the energy in heat exchange compared to the energy you put in. You don't produce heat, you exchange it. https://www.wolf.eu/en-de/advisor/cop-heat-pumps https://www.wolf.eu/en-de/advisor/cop-heat-pumps
    - elil17 4y ago
      I think you are misunderstand where most of that energy comes from. Say I have some refrigerant in liquid form at a low pressure. That refrigerant will have a boiling point of say, -20 degrees F. I use the ambient air, which is say 0 degrees F, to boil the refrigerant into a gas. The internal energy of the refrigerant goes up significantly, but it's temperature does not change. Then, I compress the gas so that it goes up in temperature. This change in temperature does not correspond to a large change in the internal energy of the gas. The same energy is pushed closer together, resulting in a higher temperature[1]. Then, I condense the gas at it's new boiling point, say 100 F, into a liquid. Then you decompress the resulting liquid and the cycle repeats. Most of the energy is coming from the ambient air, only a small amount of electricity is used to change what temperature that energy is available at. [1] A very simple mental model you can use to understand the difference between temperature and energy for a gas is that temperature is the number of times the gas molecules bump into each other in a second, while energy is how fast the gas molecules are moving. So if you have a very low pressure gas, even all of those molecules have a ton of energy in the form of motion, the temperature of the gas will be quite low because the gas molecules won't interact often. But compress that gas down to a small volume, and the molecules will bump into each other all the time even though they don't have much more energy.
- nicoburns 4y ago
  Well of course when talking about efficiency you have to specify what you are being efficient with respect to: what's most energy efficient might be different to what's most cost efficient which might be different to what's most carbon efficient. Cost is going to vary greatly on the electricity and gas prices in your area, so it's hard to give a definitive answer there. With regards to energy efficiency, my understanding is that heat pumps can be up to 400% (300% typical), which is naively much better than gas which is at most 90% efficient (70-80% typical). This doesn't take into account the extra innefficiency of generating the electricity in the first place, but a quick google tells me coal plants are typically 33% efficient, with combined cycle gas plants being typically being 50% efficient. Even at those levels, heat pumps still look to be coming out ahead to me. And that's not even taking into the possibility of green energy generation through renewables or nuclear.
  - zeroonetwothree 4y ago
    There is also up to 10% loss from transmission/distribution. So that makes the two closer though heat pumps still win.
  - elil17 4y ago
    Yes, heat pumps do win. They win even more when you consider that the energy mix is not 100% fossil fuels. Globally something like 15% of energy comes from renewables or nuclear, plus 20-ish % from natural gas which is, as you said, 50-ish % efficient in turbine power plants.
- gabrielhidasy 4y ago
  They literally are more efficient than burning gas, a good heat pump can do over 300% efficiency (KWs of heat in your house vs KWs of electricity used) while a furnace can only hope to get 100%. Even if the heat pump is fed from gas power plants (which burn gas with about 50-60% efficiency, more if the waste heat is reused), they are still using less gas for the same amount of heat than directly burning it.
  - nashashmi 4y ago
    400% efficiency? Is that even possible? (Did AI write this?)
    - thehappypm 4y ago
      Yes, you might want to do some research on it. The core idea is that you aren’t using 1 unit of electrical energy to create 1 new unit of heat energy. You are using 1 unit of electrical energy to capture several units of pre-existing heat energy from the environment and pump it indoors.
    - sbradford26 4y ago
      So the term efficiency with heat pumps typically refers to COP Coefficient of Performance. It a measure of how many watts of heat you are able to pump per given watt of electricity used. So 400% would be a COP of 4.0 which is definitely possible with air source heat pumps in milder weather and ground source heat pumps in pretty much any weather.
    - Nihilartikel 4y ago
      If I can spend 1 joule to transfer two joules of enthalpy from outside to inside, then that is 200% efficiency. Burning 1 joule of gas would give you 1 joule of heat in a perfect world. That is what a non pump does.
      - vikingerik 4y ago
        Where exactly does that first spent joule go, thermodynamically speaking? Is it also converted to heat within the electromechanicals of the heat pump?
- SigmundA 4y ago
  They can be, natural gas is about 1000 BTU per cubic foot. An expensive high efficiency gas furnace might be 95% efficient (most normal furnaces are in the 80's) 1000 x 0.95 = 950 BTU/cuft A high efficiency natural gas power plant is 60% efficient and a modern high efficiency low temp heat pump can have a COP up to around 2.7 at 17F 1000 x 0.6 x 2.7 = 1620 BTU/cuft A 40% power pant is still more efficient than a 95% furnace with a 2.7 COP heat pump. There is obviously more to this, there are some grid losses to account for but has to be compared to piping losses, there is also cost factors and also how much renewable is mixed into your grid supply, but generally once that heat pump is above around 2.5 COP it starts to make sense, this is a no brainer in milder climates which is why I have a heat pump and no gas furnace here in FL even though I have gas to the house for other uses.
  - snuxoll 4y ago
    > this is a no brainer in milder climates which is why I have a heat pump and no gas furnace here in FL even though I have gas to the house for other uses. They're a no-brainer in every climate. Newer heat pumps can handle fairly cold temperatures (-13°F) pretty easily, there may be a loss in efficiency but in the majority of the world it doesn't stay that cold. A few days of lower than normal efficiency, and at worst plugging in a few space heaters if it gets extremely cold for a day or two, does not change the overall math of heat pumps being a better solution. Hell, that's just me talking about air source heat pumps. No reason for new construction to not use ground source and get better efficiency and not worry about ambient outdoor temperatures.
    - nashashmi 4y ago
      Ok! I am genuinely interested in how heat pumps are more efficient. My online search led me to calling heat pumps more efficient when compared to electric heaters. And better in other ways compared to gas burners. But lord's sake, they were all upselling marketing sites for heat pumps. I am looking for genuine research, and not from paid mouth pieces. Majority of the comments here seem like agents of heat pump industry. And HN rules forbid me from calling them that.
- Nihilartikel 4y ago
  The new order world government will have to pry my wood burning lightbulbs from my cold dead guns!
- SigmundA 4y ago
  Just to counter your edit: >But compressing and decompressing is not an energy efficient task. It takes a lot of work. Mechanical inefficiencies are a huge energy consumption. Gas is simply burning fuel. Yes, we should save gas for rainy days. But I hate to say that it is more efficient and cheap. There is no comparison. You are very mistaken, the energy required to compress refrigerant is less than the energy captured and delivered if COP > 1, which is the point of a heat pump. At COP 1 it is basically heat of compression and equal to a resistive heater at COP greater than 2 the heat pump captured more heat from the environment than used to compress the refrigerant. I am not sure if you are arguing in good faith, if so here are some of the simplest resources I can find to explain how a heat pump can exceed a furnace in efficiency even when taking power plant and transmission losses into account, with easy to understand graphics: https://greenbusinesswatch.co.uk/cop-vs-spf https://greenbusinesswatch.co.uk/cop-vs-spf https://energyeducation.ca/encyclopedia/Coefficient_of_performance https://energyeducation.ca/encyclopedia/Coefficient_of_perfo... http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatpump.html http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatpump.h... This should really be taught and drilled in lower education, the difference between heat and temperature and relationship to power, how heat engines work, etc. This stuff basically makes modern society possible and we will never progress in decoupling our power sources from use of the power which is what electrification allows which allows us to transition away from throwing carbon up in the air for energy.
vintermann 4y ago
Yeah. If some people came together at Davos or whatever and decided "we need to promote heat pumps!", you can be sure they would mess it up. Consent can maybe be manufactured. Enthusiasm is organic, for good and bad.
- aliqot 4y ago
  It's like you got to the endzone and fumbled with <5yds
- nicoburns 4y ago
  Agreed that top-down programs aren't always very effective (although sometimes they can be), but would point out that "coordinated" doesn't imply top-down. It could just mean that lots of individual entities are working with each other to achieve a common goal.

nashashmi 4y ago

They are not more energy efficient than burning gas. Edit: since i am getting downvoted to oblivion, let me fight back here. I genuinely wished heat pumps would be more efficient and in theory they can be. I would love to not generate heat and just use the outside heat energy and compress it down into a smaller location. But compressing and decompressing is not an energy efficient task. It takes a lot of work. Mechanical inefficiencies are a huge energy consumption. Gas is simply burning fuel. Yes, we should save gas for rainy days. But I hate to say that it is more efficient and cheap. There is no comparison.

pjerem 4y ago
Yes they are. You get more heating from an heat pump running from electricity coming from gas plants than what you get by just burning the gas. Including losses on the grid.
- nashashmi 4y ago
  I cannot imagine this in anyway. Heat pumps work like ACs do. They do compress a medium till it heats up, and then spread that heat around. And then they decompress until it cools down and dump that cold until outside heat brings up the temperature again. Those compressions and decompressions take up immense amounts of energy. They are less efficient than simply burning gas. On the flip side, could we not create electricity generation and heating from Natural gas?
  - baxuz 4y ago
    That's the whole point. For most modern systems you get >4x of the energy in heat exchange compared to the energy you put in. You don't produce heat, you exchange it. https://www.wolf.eu/en-de/advisor/cop-heat-pumps https://www.wolf.eu/en-de/advisor/cop-heat-pumps
  - elil17 4y ago
    I think you are misunderstand where most of that energy comes from. Say I have some refrigerant in liquid form at a low pressure. That refrigerant will have a boiling point of say, -20 degrees F. I use the ambient air, which is say 0 degrees F, to boil the refrigerant into a gas. The internal energy of the refrigerant goes up significantly, but it's temperature does not change. Then, I compress the gas so that it goes up in temperature. This change in temperature does not correspond to a large change in the internal energy of the gas. The same energy is pushed closer together, resulting in a higher temperature[1]. Then, I condense the gas at it's new boiling point, say 100 F, into a liquid. Then you decompress the resulting liquid and the cycle repeats. Most of the energy is coming from the ambient air, only a small amount of electricity is used to change what temperature that energy is available at. [1] A very simple mental model you can use to understand the difference between temperature and energy for a gas is that temperature is the number of times the gas molecules bump into each other in a second, while energy is how fast the gas molecules are moving. So if you have a very low pressure gas, even all of those molecules have a ton of energy in the form of motion, the temperature of the gas will be quite low because the gas molecules won't interact often. But compress that gas down to a small volume, and the molecules will bump into each other all the time even though they don't have much more energy.
nicoburns 4y ago
Well of course when talking about efficiency you have to specify what you are being efficient with respect to: what's most energy efficient might be different to what's most cost efficient which might be different to what's most carbon efficient. Cost is going to vary greatly on the electricity and gas prices in your area, so it's hard to give a definitive answer there. With regards to energy efficiency, my understanding is that heat pumps can be up to 400% (300% typical), which is naively much better than gas which is at most 90% efficient (70-80% typical). This doesn't take into account the extra innefficiency of generating the electricity in the first place, but a quick google tells me coal plants are typically 33% efficient, with combined cycle gas plants being typically being 50% efficient. Even at those levels, heat pumps still look to be coming out ahead to me. And that's not even taking into the possibility of green energy generation through renewables or nuclear.
- zeroonetwothree 4y ago
  There is also up to 10% loss from transmission/distribution. So that makes the two closer though heat pumps still win.
- elil17 4y ago
  Yes, heat pumps do win. They win even more when you consider that the energy mix is not 100% fossil fuels. Globally something like 15% of energy comes from renewables or nuclear, plus 20-ish % from natural gas which is, as you said, 50-ish % efficient in turbine power plants.
gabrielhidasy 4y ago
They literally are more efficient than burning gas, a good heat pump can do over 300% efficiency (KWs of heat in your house vs KWs of electricity used) while a furnace can only hope to get 100%. Even if the heat pump is fed from gas power plants (which burn gas with about 50-60% efficiency, more if the waste heat is reused), they are still using less gas for the same amount of heat than directly burning it.
- nashashmi 4y ago
  400% efficiency? Is that even possible? (Did AI write this?)
  - thehappypm 4y ago
    Yes, you might want to do some research on it. The core idea is that you aren’t using 1 unit of electrical energy to create 1 new unit of heat energy. You are using 1 unit of electrical energy to capture several units of pre-existing heat energy from the environment and pump it indoors.
  - sbradford26 4y ago
    So the term efficiency with heat pumps typically refers to COP Coefficient of Performance. It a measure of how many watts of heat you are able to pump per given watt of electricity used. So 400% would be a COP of 4.0 which is definitely possible with air source heat pumps in milder weather and ground source heat pumps in pretty much any weather.
  - Nihilartikel 4y ago
    If I can spend 1 joule to transfer two joules of enthalpy from outside to inside, then that is 200% efficiency. Burning 1 joule of gas would give you 1 joule of heat in a perfect world. That is what a non pump does.
    - vikingerik 4y ago
      Where exactly does that first spent joule go, thermodynamically speaking? Is it also converted to heat within the electromechanicals of the heat pump?
SigmundA 4y ago
They can be, natural gas is about 1000 BTU per cubic foot. An expensive high efficiency gas furnace might be 95% efficient (most normal furnaces are in the 80's) 1000 x 0.95 = 950 BTU/cuft A high efficiency natural gas power plant is 60% efficient and a modern high efficiency low temp heat pump can have a COP up to around 2.7 at 17F 1000 x 0.6 x 2.7 = 1620 BTU/cuft A 40% power pant is still more efficient than a 95% furnace with a 2.7 COP heat pump. There is obviously more to this, there are some grid losses to account for but has to be compared to piping losses, there is also cost factors and also how much renewable is mixed into your grid supply, but generally once that heat pump is above around 2.5 COP it starts to make sense, this is a no brainer in milder climates which is why I have a heat pump and no gas furnace here in FL even though I have gas to the house for other uses.
- snuxoll 4y ago
  > this is a no brainer in milder climates which is why I have a heat pump and no gas furnace here in FL even though I have gas to the house for other uses. They're a no-brainer in every climate. Newer heat pumps can handle fairly cold temperatures (-13°F) pretty easily, there may be a loss in efficiency but in the majority of the world it doesn't stay that cold. A few days of lower than normal efficiency, and at worst plugging in a few space heaters if it gets extremely cold for a day or two, does not change the overall math of heat pumps being a better solution. Hell, that's just me talking about air source heat pumps. No reason for new construction to not use ground source and get better efficiency and not worry about ambient outdoor temperatures.
  - nashashmi 4y ago
    Ok! I am genuinely interested in how heat pumps are more efficient. My online search led me to calling heat pumps more efficient when compared to electric heaters. And better in other ways compared to gas burners. But lord's sake, they were all upselling marketing sites for heat pumps. I am looking for genuine research, and not from paid mouth pieces. Majority of the comments here seem like agents of heat pump industry. And HN rules forbid me from calling them that.
Nihilartikel 4y ago
The new order world government will have to pry my wood burning lightbulbs from my cold dead guns!
SigmundA 4y ago
Just to counter your edit: >But compressing and decompressing is not an energy efficient task. It takes a lot of work. Mechanical inefficiencies are a huge energy consumption. Gas is simply burning fuel. Yes, we should save gas for rainy days. But I hate to say that it is more efficient and cheap. There is no comparison. You are very mistaken, the energy required to compress refrigerant is less than the energy captured and delivered if COP > 1, which is the point of a heat pump. At COP 1 it is basically heat of compression and equal to a resistive heater at COP greater than 2 the heat pump captured more heat from the environment than used to compress the refrigerant. I am not sure if you are arguing in good faith, if so here are some of the simplest resources I can find to explain how a heat pump can exceed a furnace in efficiency even when taking power plant and transmission losses into account, with easy to understand graphics: https://greenbusinesswatch.co.uk/cop-vs-spf https://greenbusinesswatch.co.uk/cop-vs-spf https://energyeducation.ca/encyclopedia/Coefficient_of_performance https://energyeducation.ca/encyclopedia/Coefficient_of_perfo... http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatpump.html http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatpump.h... This should really be taught and drilled in lower education, the difference between heat and temperature and relationship to power, how heat engines work, etc. This stuff basically makes modern society possible and we will never progress in decoupling our power sources from use of the power which is what electrification allows which allows us to transition away from throwing carbon up in the air for energy.

vintermann 4y ago

Yeah. If some people came together at Davos or whatever and decided "we need to promote heat pumps!", you can be sure they would mess it up. Consent can maybe be manufactured. Enthusiasm is organic, for good and bad.

aliqot 4y ago
It's like you got to the endzone and fumbled with <5yds
nicoburns 4y ago
Agreed that top-down programs aren't always very effective (although sometimes they can be), but would point out that "coordinated" doesn't imply top-down. It could just mean that lots of individual entities are working with each other to achieve a common goal.