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? @[email protected]

  • xigoi
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    5010 months ago

    Doesn’t the light turn into heat anyway as soon as it’s absorbed?

    • Fubber Nuckin'
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      4510 months ago

      I mean if you want to go that route, we could just say that every speaker, light source, motor, etc is 100% efficient at generating heat because all of its energy output will eventually become heat.

      • xigoi
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        4110 months ago

        That is also completely true, but meaningless because heat generation is not the purpose of these devices. However, if you use them in a building heated by a thermostat-controlled electric heater, you’re effectivhly running them for free.

        • @[email protected]
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          1410 months ago

          I‘m was using two old servers with folding@home running as space heaters in the winter. I got them for dirt cheap and thought if I convert electricity into heat, I might as well do something good with it. Also nice opportunity to run a minecraft server for the kids during that time.

        • @[email protected]
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          10 months ago

          I‘m was using two old servers with folding@home running as space heaters in the winter. I got them for dirt cheap and thought if I convert electricity into heat, I might as well do something good with it. Also nice opportunity to run a minecraft server for the kids during that time.

      • @[email protected]
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        410 months ago

        Energy can neither be created nor destroyed so in the grand scheme of things, everything is 100% energy efficient one way or another.

      • @[email protected]
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        110 months ago

        I suggest we submit proposals to define “100%” and “efficient” before we design the experiment

    • lad
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      810 months ago

      The visible part of the spectrum is likely going to be absorbed somewhere far away from the place you’re trying to heat up. Also, I’m not educated enough to tell if there will be further losses of energy

      • @[email protected]
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        410 months ago

        If it’s in a room the visible radiation will still just heat up the room. If you’re using it outdoors and point it away then yeah you’ll have some waste.

        • lad
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          410 months ago

          Not sure if visible radiation that leaves through a transparent window will still heat up only inside the room, that what I meant. Probably should have phrased it better

      • @[email protected]
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        10 months ago

        that’s only true if you shine it out a very large the window

        normally windows cover a quite small fraction of a rooms surface area

        but sure, if a few fractions of a percent leave through a window, i guess its technically not a 100% effective space heater, if we define the work as heating only the relevant room.