• anivia@lemmy.ml
    link
    fedilink
    arrow-up
    9
    ·
    edit-2
    4 months ago

    One thing to account for is that humans are very inefficient at converting food into energy output. Only about 25% efficient to be precise. So you need to eat about 4 times more calories than you end up outputting into the bicycle.

    The same thing applies to ICE cars, their engines are also very inefficient. EVs however reach an efficiency of 80-90%, they only end up using more energy than a bicycle because of how much faster you usually drive them. But if you drove an EV at the same speed you would ride a bicycle they would be vastly more efficient. And that’s not even accounting for the amount of energy used to produce food in the first place, which is a lot higher than the energy content of said food.

    The superior choice is obviously an electric bicycle though when you want to have the most sustainable transportation, you get all of the efficiency gains from a battery operated motor, whilst still having the low weight and drag of a bicycle

    • booly@sh.itjust.works
      link
      fedilink
      arrow-up
      1
      ·
      4 months ago

      EVs however reach an efficiency of 80-90%,

      That’s not accounting for the inefficiency of turning heat into electricity in the first place (turbine generation is about 90% at utility scale) or turning photons into usable electricity (photovoltaics are at about 20%). And with turbines, you have to account for the inefficiencies in processing the fuel to get it to that point.

      The whole universe is just an entropy generator and we’re gonna lose a lot of useful energy as we try to manipulate it.

      • anivia@lemmy.ml
        link
        fedilink
        arrow-up
        1
        ·
        4 months ago

        Yes, I was purely referring to the efficiency of the battery and motor. Producing food also requires a significantly more energy than the food ends up containing