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Japanese automakers Honda and Nissan have announced plans to join forces and form the world’s third-largest automaker by sales as the industry undergoes dramatic changes in its transition away from fossil fuels.

  • ilinamorato@lemmy.worldEnglish
    254·
    3 days ago

    Ok, I see misinformation like this on like every social media site now. I didn’t know it had made it to Lemmy.

    So, you know that conversion of energy causes energy loss, right? So how is it that converting that energy four times (original source > electricity > hydrogen > electricity > motion) sounds more efficient to you than converting that energy twice (original source > electricity > motion)?

    Especially when you consider that electricity already has a network of well-established, proven, global distribution infrastructure whose transfer loss has been obsessively optimized over the last century, while hydrogen emphatically does not?

    From the point of view of pure physics, it makes more sense to charge up a bunch of batteries and put them on a truck than to put a bunch of fuel cells onto that same truck. And remember, you can make those batteries more convenient by sending the electricity through the grid instead.

    Charging times are quickly decreasing. They’ll eventually reach a reasonable parity with gas tank fills, but they’ll have become the dominant transportation energy source long before that. The current state of battery technology is the worst that it will ever be, and multiple industries are working together to make them better. Hydrogen pretty much only has wide applications to one industry.

    Would all of this have been true if both technologies were starting from zero? Probably not. But electricity has a hundred year head start over hydrogen in the consumer space, and a lot of money is still being put into it. Plus, it’s obviously going to be the eventual winner because physics, so why bother with the transitional source when what we would transition to is already a more mature technology?

    The war is long over, and anyone who pretends otherwise is just ignoring the laws of physics.

    Edit: I recognize that I’m papering over the transfer loss of electricity > battery > electricity. That’s because the transfer loss of charging a battery is <10%, while the transfer loss of generating hydrogen is >20%.

    • nixcamic@lemmy.worldEnglish
      7·
      3 days ago

      While I agree that hydrogen is inherently inefficient, most batteries don’t store electricity as such, you’re still going electrical > chemical > electrical.

      • punkfungus@sh.itjust.worksEnglish
        6·
        3 days ago

        Hydrogen, even with fuel cell/electric, is not suitable for rural car owners. It’s only really suitable for vehicles that are constantly running, like freight trucks. Why? Because hydrogen leaks out of any vessel you try to put it in. It’s the smallest element in the universe so it slips past the molecules of whatever sealing material you are using. It will even permeate through solid metal, making said metal brittle in the process. And this problem of course gets worse at higher pressures, which you have to use to get any energy density.

        So not only do you have to contend with the terrible efficiency loss of using electricity to create hydrogen only to turn it back into electricity again, a whole bunch of your fuel is constantly leaking out during transport and storage. And then if you use cryogenic hydrogen for the best energy density it gets worse again because you can’t keep it cold enough. It’s constantly boiling off and has to be vented to prevent your tank from exploding.

        So even if you solve all the myriad other implementation problems with hydrogen, you’re never escaping the fact that you need to use all your fuel quickly or you’re setting money on fire as it leaks. Not to mention potentially getting stuck because you didn’t drive your car for a few days and now you don’t have the fuel to reach a fill station.

        Hence why, if it ever matures enough to become actually viable, it will almost certainly be limited to freight and courier type vehicles. They run near constantly and so burn through fuel fast enough that the leakage isn’t an issue.