If a machine is never 100% efficient transforming energy into work because part of the energy is converted into heat, does it mean an electric heater is 100% efficient? @showerthoughts@lemmy.world

  • JohnDClay@sh.itjust.works
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    4 months ago

    But you can heat an area with ‘better than 100% efficiency’ if you use a heat pump and move heat from one place to another. Coefficients of performance (cop) of about 2.5 I think are pretty common, meaning if you put 100 watts into moving heat, the area will get 250 watts warmer.

    • cosmic_skillet@lemmy.ml
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      4 months ago

      Total amount of heat for the entire closed system does not increase over 100% of energy used to drive the heat pump. Like you said, you just moved heat around