Toyota boasts new battery technology with 745-mile range and 10-minute charging time — here’s how it may impact mass EV adoption::The potential to significantly reduce pollution could be huge.

  • @TheGrandNagus@lemmy.world
    link
    fedilink
    English
    97 months ago

    Hydrogen cars cannot be better than battery electric cars, because the laws of physics doesn’t allow them to be.

    A HFCEV is just a BEV with extra steps and efficiency losses. Reverse hydrolysis is used to generate electricity (with losses) that in turn charges a small battery that drives the car.

    Smaller batteries can’t provide the same amount of power as larger batteries (that’s why the fastest EVs always have large batteries and why performance drops as the battery gets close to empty).

    Already it’s a loss for HFCEVs, but the bad news doesn’t end there - that ultra-pressurised hydrogen doesn’t just magically appear in your tank. So we need to look into that. In fact, let’s look at the whole process.

    I’m going to be very generous here and assume that all hydrogen is produced with green energy - this obviously isn’t the case. Hydrogen production is far more carbon-intensive than almost all national electricity grids are.

    BEV:

    Electricity is generated, and sent over power lines until it makes its way to a charger. This charger directly charges the battery of the car (whole process, typically over 90% efficient). The battery drives the electric motor. The car moves (electric motors, 90-97% efficient).

    HFCEV:

    First water must be collected and purified. I don’t know how energy intensive that is, but it could be a lot. Then it needs to undergo hydrolysis, which is extremely energy intensive. The hydrogen needs to be pumped out and compressed, which requires yet more energy. From there, the hydrogen needs to be loaded onto transport, be it shipping tankers, trucks, trains. It needs to be physically transported, which is more energy. Then if it was on a tanker or train it needs to be put into smaller distribution vehicles. Then transported to a fueling station. The pumps and station needs a lot of energy to run. People fill their cars up. The car runs an (again quite energy intensive) reverse hydrolysis, which charges the battery and powers the electric motor.

    There’s a lot more “work” being done than sending electrons down wires.

    And this is before we even get into things like infrastructure or safety. A typical hydrogen fueling station costs over $5m to build, in part due to the safety regs of pressurised hydrogen being a very explosive substance (and fueling stations have blow up before, despite them virtually not existing).

    Chargers range from $600 to $10k each. Say a location has 20 of them. That’s still pennies compared to a hydrogen fueling station. Petrol stations cannot be used for hydrogen. They look the same but they are not the same, even ignoring all the additional safety requirements.

    Electricity on the other hand has infrastructure everywhere, even wired directly to our homes. Electricians exist everywhere, it’s a widely understood technology and pretty much any electrician is capable of installing at least a home charger.

    Sorry for the rant, but no, HFCEVs will not take off. They’re vastly more complex. More expensive. Less safe. Less performant. Nowhere near as energy efficient. There’s not really any angle you can look at where they make sense even if we assume battery tech completely stagnates.