this post was submitted on 01 Nov 2023
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It never ceases to amaze me how people don't read past the title π€¦ There are people debating about -10 to -30C when the article clearly states that it works in those temperatures. Not only does it work, it's twice as efficient as electrical heating at those temperatures.
I think it does, and it seems to work because of a defrosting feature that earlier models didn't have. But I wouldn't say it does so very clearly. Unless I missed it.
Electric heat is not always 99.9% efficient, resistive heating is.
Heat pumps are more than 100% efficient(compared to resistive heating)
It's not bs, because we are moving heat, not creating it. You thinking it is bullshit will not change the laws of thermodynamics. Try to think about it this way.
"Cold" is a made up human concept, it really is a lack of heat energy. The coldest is 0K, but even a Midwest winter is waaaaaay above that. Heat pumps (and all refrigerant-based systems) work by changing the phase of the refrigerant from liquid to gas to cool, or by compressing a gas to a liquid. This phase change takes energy from the surrounding air (think about computer duster, the can gets cold) and then pipes it inside, where it can be compressed to release the heat it just picked up from outside. In the summer you flip the reverse switch to cool your house.
Here is an explanation from someone much more eloquent than myself:https://youtu.be/7J52mDjZzto?si=sYlNlpvGnJs16lwk
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Do you understand how heat pumps work? The heat you're drawing on is the the heat of the outside compartment on the outside, therefore the heat moved to the inside can be more than just the heat equivalent of the electric energy you put in. That's how these achieve more than 100% efficiency, in general. In fact if the outside isn't so cold outside they can achieve 300%-500%.
Now the trick to moving heat from a cold outside compartment to a warmer inside compartment lies in the compression. If you draw even a moderate amount of heat energy into your medium, then compress it, it will turn quite hot allowing you to dump heat into your warm inside compartment. Then as the medium flows out you let it expand and it turns really cold, cold enough that it can draw in heat from the cold outside. But the lower the difference in temperature of the outside air to your expanded medium gets the less heat you can transport per unit of time, that's why we're only looking at 200% here.
You also have the waste heat being converted into useful heat, which only helps the efficiency. A standard resistive heater is almost all waste heat, so if you can use some of that energy to get more heat from elsewhere, that's how you can get 100%+ heat efficiency.
So you'd rather trust your feelings? Just loon into it if you're that skeptical.
Arrogantly uninformed. It's an impressive combination
"at those temperatures"
well, to a heat pump even -40Β° is still 230K, which is plenty of energy to move around and work with. It may be cold to you, but to a heat pump it's not.
Don't you just love it when people decide things are true because they feel it's true?