I use it to heat my house.

  • @mvirts
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    2211 months ago

    Ive been testing combustion engines made of wood but keep getting more energy out than I put in…

  • Troy
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    1211 months ago

    Lisa, in this meme we obey the laws of thermodynamics!

  • @buycurious
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    1011 months ago

    Sorry, I’m a bit dumb for this one.

    Could someone please explain?

    • Dem Bosain
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      4911 months ago

      There’s no such thing as a 100% efficient “engine”. But in this case, since the waste heat is put to use (heating the house), OP thinks there’s a loophole.

      But, house would also need to be soundproof. Any noise leaking to the outside is lost energy.

      • @Ellie_The_Nurse
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        11 months ago

        Ah, but that’s by design: it also acts as a soothing white noise machine.

        Then you might point out the exhaust and all it’s associated wastes, but that’s by design: it produces a heady and aromatic product for recreational huffing.

        Then you might point out the vibrations, but that’s by design: the engine also provides invigorating massages to relax taut muscles.

        • @[email protected]OP
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          911 months ago

          Don’t tell anyone, but I actually only used 1 significant figure, so anything above 50% will do.

          I’m also using the version of significant figures where I work backwards from the answer, otherwise I’d need 95% or higher and that’s too difficult.

    • @[email protected]OP
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      3011 months ago

      Most engines are less than 30% efficient at producing movement. The majority of the energy is lost as heat.

      Thermodynamics tells us that pretty much all energy ends up as heat. In a closed system, any device that uses energy is 100% efficient at making heat. A 1000W computer will make exactly as much heat as a 1000W heater.

      A 100% efficient engine can only exist if the desired output is heat, thus making it a pretty useless engine. Also, in a closed system, the exhaust cannot leave.

      • @[email protected]
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        1011 months ago

        A 1000W computer will make exactly as much heat as a 1000W heater.

        All space heaters should be coin miners (or some other borderline useless energy wasting tech, like AI training). Change my mind.

        • @owenfromcanada
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          311 months ago

          If you want to be philanthropic, there are programs you can run that use your computer’s idle time to process data for cancer research and such.

        • @someguy3
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          211 months ago

          You can sign up for research crunching.

      • Hello_there
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        311 months ago

        But even a furnace/fireplace is subject to incomplete combustion, where some portion of the wood is transformed into byproducts that rob some of the energy of the fire. There’s actually a big difference in the amount of energy you can get out of a fire, depending on the type of stove that’s used.
        That’s some of what NGOs have tried to do for developing countries - find cheap and easily produceabke stove designs that can reduce the amount of wood needed and improve air quality in the home.

        • @someguy3
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          211 months ago

          Yes he is incorrect. NG furnace is 95% efficient iirc.

  • @[email protected]
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    811 months ago

    I’m more impressed by that fact that if either runs perfectly silent or that your house has perfect sound insulation

  • @muntedcrocodile
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    811 months ago

    Wait till you hear about reverse cyxling air conditioning it exceeds 100% efficiency.

  • @[email protected]
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    611 months ago

    this is true only if you dont vent the exhaust outside making the air inside quite fun to breathe

  • TheOneCurly
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    211 months ago

    It’s only 100% efficient if you’re also letting all the exhaust into the house too…

  • @someguy3
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    11 months ago

    Fyi I think they’re around 95%.