Can’t you just break down water, use the hydrogen to power the electric motor, and I don’t think O2 as a byproduct is bad, now this is of course an ideal condition, but why hasn’t this been looked into more?

  • Gigan@lemmy.world
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    5 months ago

    I’m not a chemist/physicist, but if I had to guess it’s because it takes more energy to break apart the water into Hydrogen than what you will get by burning the Hydrogen to power the motor.

    • BlameThePeacock@lemmy.ca
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      5 months ago

      Your guess is accurate.

      The other side of the issue is that “water” is rarely only water. There are tons of other shit floating in the water that cause problems with the splitting process, so you usually have to clean the water first which takes even more energy/resources.

  • DeltaTangoLima@reddrefuge.com
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    5 months ago

    As a lot of people have already said, breaking water down into hydrogen and O2 requires more energy than that produced by running a car on hydrogen.

    Luckily, there’s some promising research underway, on solar panels that converts water vapour in the air into hydrogen. Last I read, they’re approaching kilowatt scale, but it takes a big system to produce just 500 grams of hydrogen in a day. Which will only produce around 2kW of output power.

    Assuming they can somehow make all of that much smaller, and produce much, much more hydrogen from that smaller system, there’s the secondary problem of storing and pressurizing the hydrogen produced, for use in a vehicle. That will take more energy again.

  • peto@lemm.ee
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    5 months ago

    “Hydrogen powered” generally means burning hydrogen in oxygen to make water: 2(HH) + OO -> 2(HHO). To run a car on water as you say is a lot like trying to make a fire out of ash, rather than wood. You can’t burn the ash because it has already been burned.

    • dustyData@lemmy.world
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      5 months ago

      Technically speaking, no one outside of college demonstration engines are burning hydrogen. Almost all hydrogen powered EVs use fuel cell stacks that mediate the proton exchange through an electrolyte. This allows the capture of far more energy than could be possible by just letting the hydrogen burn, as in a internal combustion engine, for example.

    • fastandcurious@lemmy.worldOP
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      5 months ago

      Kinda like internal combustion, you can probably use a battery or something to start it and then use part of the energy from the motor to further continue the process, but yeah lol this seems wishful thinking🤷🏼‍♂️

      • Nollij@sopuli.xyz
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        5 months ago

        That would be a perpetual motion machine, and violate the first law of thermodynamics.

        The amount of energy you get by burning hydrogen (creating water) is exactly the same as you spent to split water into hydrogen and oxygen.

        • fishos@lemmy.world
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          5 months ago

          No it’s not. They’re referring to exactly what a car or fusion does. To “break even”( in fusion terms), you must produce more energy than is being put in to maintain it. In a car, you turn some of that combustion power back into electrical power via the alternator and recharge the battery that you used to start the car.

          They’re just asking if the same principle can apply: using a quick burst of auxillary power to get it going that you then recoup from the excess power created by the hydrogen combustion. And keep in mind, you ARE creating excess power. It’s what moves the vehicle lol.