I use it to heat my house.

  • mvirts@lemmy.worldEnglish
    22·
    il y a 11 mois

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

  • Troy@lemmy.caEnglish
    13·
    il y a 11 mois

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

    • Dem Bosain@midwest.socialEnglish
      501·
      il y a 11 mois

      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@lemmy.worldEnglish
        23·
        il y a 11 mois

        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.

        • 18107OPEnglish
          9·
          il y a 11 mois

          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.

    • 18107OPEnglish
      29·
      il y a 11 mois

      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.

      • RvTV95XBeo@sh.itjust.worksEnglish
        111·
        il y a 11 mois

        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.

      • Hello_there@kbin.social
        3·
        il y a 11 mois

        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.

  • EmoDuck@sh.itjust.worksEnglish
    8·
    il y a 11 mois

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