Not really - hydrogen shoots straight up into the atmosphere, whereas petrol both pools in the area and also turns to gas and mixes with air quite easily (which is why it's used as a fuel in the first place)
In practice, hydrogen cars are quite safe. They're just not worth the cost in infrastructure and lack of efficiency compared to BEVs.
It also depends on storage method. Cryogenic and compressed hydrogen have extreme risks completely unrelated to the flammability of the gas itself, while various metal hydride options are mostly a danger if you drop the tank on your foot.
> They're just not worth the cost in infrastructure and lack of efficiency compared to BEVs.
Don't BEVs weigh more than hydrogen cars, given the same model and range? That would give at least some incentive to use hydrogen over BEV, as it decreases road wear, which reduces the costs associated with the operation of that car.
Additionally, hydrogen cars could be considered safer once they've gotten into an accident, as risk of battery thermal runaway wouldn't usually be an issue for extended periods of time in hydrogen cars, whereas several car carrier ships have been lost due (in part or in full) to battery fires.
Even if car registration was taxed completely commensurate with their road wear (i.e. weight) the difference wouldn't be enough to move people over from BEV given the lack of refilling options.
Gas still has the infrastructure, but batteries are closer to having what they need than hydrogen for critical adoption.
Unless you're in the upper Midwest and your car is one of those stuck at a charger unable to fast charge because it's too cold and you didn't have an hours worth of time and energy to preheat it.
> Unless you're in the upper Midwest and your car is one of those stuck at a charger unable to fast charge because it's too cold and you didn't have an hours worth of time and energy to preheat it.
You also have the problem where it is "too hot". Higher battery wear and all. Part of me feels the BEV revolution only considered half the northern hemisphere.
Tons of EVs on the roads in Texas. I realize there can be hotter places (Death Valley) or more humid but certainly if you can drive an BEV in the height of Texas summer that should fit more of the worlds use cases.
I think cold is a harder problem to solve, I think your delta T of environment temps and operating temps are much greater in cold weather.
Exactly. People freaking out over EV infrastructure haven't done the math - nearly all first world home electric hookups are fine for charging a couple of EVs
Right since we haven’t already used an equal or even more so flammable substance for the past century
As far as I’m aware gasoline ignites at much lower mixtures of oxygen than hydrogen. The Hindenburg can’t hurt you and if it was filled with gasoline vapors instead of hydrogen, well it would never get of the ground, but it would have been more dangerous.
Nope. Hydrogen is not just flammable, the article tells you it is EXPLOSIVE at concentration of 4 percent to 74 percent in air. If the Hindenburg was a hydrogen-air mixture, it would have leveled a large portion of the area rather than just burning where it fell.
I've worked in areas where they were developing hydrogen fuel cell vehicles at major auto makers. The facilities are equipped with collectors, detectors, and alarms, and everyone knows to GTFO if the alarm goes off. Hydrogen leaks indoors are extremely dangerous.
One time I filled a Mylar balloon with H2 by electrolysis. It floated very nicely but I was too cowardly to keep it in the house. It made a nice fireball when lit outside but no particularly notable explosion.
Encouraged by this I filled one of those grocery store vegetable bags with H2 + O2 from the same electrolysis setup (combine both outputs this time). Stoichiometric mixture! The boom was so loud I thought it was going to break my windows from about 20 feet away.
The Hindenburg is a largely misunderstood incident [1]. It was one of the safest airplane crashes of the century. As the balloon burned, flames and gasses vented upwards, keeping the cabin and passengers under the balloon safe. Moreover, the balloon descended slowly as the hydrogen was replaced by air. So slowly that most people got off once it was close to the ground. Out of 97 people only 35 died.
Hydrogen is significantly more dangerous than gasoline; and gasoline is crazy dangerous as it is.
Lower spark energy
Broader range of combustibility
Faster detonation speed (? [1])
It's only positive is it dissipated quickly, but that's not that great because it goes boom boom at 5% H2 -air. Everyone I know who has worked on combustion problems (I haven't myself, but colleagues have) give H2 a lot of respect.
[1] this one is an educated guess on my part based on the thermo.
>Lower spark energy. Broader range of combustibility ...
But not at the same time. That is important because H2 has such a wide ignition range. At the lower end of concentration it isn't much easier to ignite than other things. A readable discussion:
Gasoline is an easily-contained liquid. Gasoline-vapor/air mixtures explode under relatively limited circumstances. Vs. hydrogen is a difficult-to-contain gas, the concentration range for hydrogen/air to be explosive is extremely wide, and triggering the explosion is extremely easy.
While I do not argue the explosive nature of it, safety can be improved by embracing how fast it disperses. Think Toyota went that path with interleaved fibers in their containers' outer enclosures, to augment that effect, so it isn't sufficient for an explosion to occur.
But a hydrogen / air mixture is explosive from 4% hydrogen to 74% hydrogen, Americans love their attached garages, and most attached garages feature a perfectly-placed electric spark detonator...er, I mean electric garage door opener...which is triggered daily.
I was not clear - I agree with you. I was saying that gasoline might be explosive, but it is not likely to happen. it is remarkably tolerant of heat/spark at STP conditions.
In practice, hydrogen cars are quite safe. They're just not worth the cost in infrastructure and lack of efficiency compared to BEVs.