• Jojo, Lady of the West
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    8 months ago

    They’re more than 100% efficient (they move more watts of heat than they produce), but they’re less than ∞% efficient (they use Watts of energy still, so they still produce Watts of heat)

    • hperrin@lemmy.world
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      8 months ago

      100% efficient would mean they do their job without any waste heat. They create waste heat, therefore they are not 100% efficient.

      The only thing that is 100% efficient is an electric heater, because its job is to create heat, so it doesn’t create “waste heat”.

      • Jojo, Lady of the West
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        8 months ago

        A heat pump can heat a home by more than the energy in the electricity it uses. It’s more than 100% efficient at “converting electricity into heat in your home”. It does that by not actually covering electricity but by moving heat, and it is less than 100% efficient at converting electricity into motion, and introduces some waste heat

        • hperrin@lemmy.world
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          8 months ago

          The efficiency of a machine isn’t measured at how effective its job is, but how efficiently it does that job. If it moved heat without producing any waste heat, it would be 100% efficient. If it produces any waste heat at all it’s not 100% efficient. No machine can ever be more than 100% efficient. That would violate the laws of thermodynamics.