4 ms·

I actually believe that the opposite is true. It takes much more energy to cool off a home with AC than it does to heat a home in cold weather.

marcinzm 5y ago
No it doesn't. An AC essentially transfers more heat energy out than electricity it consumes. Most heating generates exactly as much heat as energy consumed (electric heaters, burning fuels, etc.). Heat pumps are an exception but they don't work well before freezing temperatures.
- cartoonworld 5y ago
  Yeah the defrost cycle limits the heat pumps heating ability, but AC units have a similar limit wrt how much they are able to lower the temperature of the air. AFIAK they can do about 20 F. At this point you need to do some math and add additional units and run them 24/7 nullifying this benefit. Geothermal heat pumps and good insulation solve both.
- jltsiren 5y ago
  Typical energy efficiency of heating is comparable to AC. The baseline solution is using waste heat from electricity generation and industrial processes. Geothermal heat pumps have become popular in the past decade or two, and lake/seawater heat pumps are seen as the future of district heating systems in dense cities. The big difference is insulation. On the average, houses that need heating are better insulated than houses that need air conditioning.
bliteben 5y ago
I think you are confusing the efficiency of heating sources vs the inefficiency of A/C. However A/C just moves heat, it doesn't have to create it. This is why in climates in which they are appropriate heat pumps can be even more efficient than other forms of heating. I will say there likely isn't a ton of good hard data on this for another reason, and that is that humidity plays a role, both in what temperatures are comfortable and maybe in some forms of temperature management.
- 8note 5y ago
  Huh? That hard data was half of my undergrad courses in mech
- rainbowzootsuit 5y ago
  The work put into the compressor and fan motors has to be rejected along with the heat that is transported by the refrigerant.
johngalt 5y ago
It is counterintuitive but A/C in general has a much smaller footprint than heating.

marcinzm 5y ago

No it doesn't. An AC essentially transfers more heat energy out than electricity it consumes. Most heating generates exactly as much heat as energy consumed (electric heaters, burning fuels, etc.). Heat pumps are an exception but they don't work well before freezing temperatures.

cartoonworld 5y ago
Yeah the defrost cycle limits the heat pumps heating ability, but AC units have a similar limit wrt how much they are able to lower the temperature of the air. AFIAK they can do about 20 F. At this point you need to do some math and add additional units and run them 24/7 nullifying this benefit. Geothermal heat pumps and good insulation solve both.
jltsiren 5y ago
Typical energy efficiency of heating is comparable to AC. The baseline solution is using waste heat from electricity generation and industrial processes. Geothermal heat pumps have become popular in the past decade or two, and lake/seawater heat pumps are seen as the future of district heating systems in dense cities. The big difference is insulation. On the average, houses that need heating are better insulated than houses that need air conditioning.

bliteben 5y ago

I think you are confusing the efficiency of heating sources vs the inefficiency of A/C. However A/C just moves heat, it doesn't have to create it. This is why in climates in which they are appropriate heat pumps can be even more efficient than other forms of heating. I will say there likely isn't a ton of good hard data on this for another reason, and that is that humidity plays a role, both in what temperatures are comfortable and maybe in some forms of temperature management.

8note 5y ago
Huh? That hard data was half of my undergrad courses in mech
rainbowzootsuit 5y ago
The work put into the compressor and fan motors has to be rejected along with the heat that is transported by the refrigerant.

johngalt 5y ago

It is counterintuitive but A/C in general has a much smaller footprint than heating.