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this post was submitted on 23 Sep 2023
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I don't understand how hydrogen didn't win the race. Transports and explodes just like gasoline. Make car go fast. Doesn't degrade like lithium. Can be "mined" by throwing electricity at water during times of excess generation by renewables. When you burn it, it turns into water. Has none of the national security concerns of distribution of lithium mining and production in other countries.
Hydrogen for cars is a nonsense. It is so inefficient. Unless you are making it from oil, which why the oil companies are pushing it, you lose loads of energy making it. Then it has to storages and transported, which is hard. Then the car use of it is inefficient too.
So ignoring the oil industries' "blue hydrogen", and looking only at "green hydrogen", you are looking at about 22% of the energy generated ending up pushing the car forward! With an EV it is about 73%. So hydrogen car are over 3 times more expensive to run.
Plus you can just plug in an EV anywhere. With an EV, if need be, you can charge, slowly, off a normal home socket. Of course, normally, you fit faster charging at home.
Hydrogen cars is lie pushed by big oil.
To be fair, i think it may have some use for fleet vehicles like taxis and long range buses because these are applications where being able to refill in minutes at a fuel depo you already run actually matters as compared to the stress you would put on a large battery fast charging day in day out. I also believe that Japan has a nuclear plant that is being built with the capacity to efficacy generate hydrogen directly. That being said, for personal vehicles I can’t really see the market of people who need that fast of a refil being large enough to reach the economies of scale necessary to be practical.
Afaik it has a higher energy density than common batteries, so it could be useful in things like aviation where this is the main concern and you can build special infrastructure to support it.
The frustrating thing is that a car running on hydrogen works really well, has a pretty long range and can be refueled quickly, so it looks like a good alternative. It's only when you ask how that hydrogen was made and how it arrived at the refueling station that things start to fall appart.
What about hydrogen fuel cells? They got 79% efficiency and can replace batteries of EVs right?
Yes, but turning electricity into hydrogen doesn't have 100% efficiency, during transport, storage and filling the car with hydrogen you lose some of it and only then you get to the fuel cell, which isn't very efficient in itself. And then you lose a bit more (although very little) in the electric motor. All this amounts to the 22% of the guy above (didn't check the number btw, but it sounds plausible)
Toyota bet on this and it didn't go anywhere in the US. They're pivoting to battery EVs.
Even countries that invested heavily in hydrogen are pulling back - like Denmark eliminating all hydrogen stations. https://energywatch.com/EnergyNews/Renewables/article16432608.ece
You can use liquified hydrogen which need to be chilled and insulated, and will evaporate away in a short time if not properly sealed
Or you use compressed hydrogen which means you are basically carrying an IED that weighs several hundred kilograms with the amount of pressure inside the gas tank
And hydrogen combustion is as others have said, inefficient.
Another issue is that you also need to use basically pure oxygen if you want to use a hydrogen fuel cell, otherwise the catalyst inside the cell would get poisoned
And well, there is a car that did all that, the Toyota Mirai, but that also pretty much ended in commercial failure, due to lack of hydrogen filling infrastructure and a whole load of other reasons.
Everybody keeps talking about all the problems storing hydrogen, but that's just quitter talk. You know how you solve 'em quick and easy? You simply combine the hydrogen with some carbon to make a convenient liquid fuel! As a bonus, you don't even need to develop fancy new fuel cell tech: you can burn it in the same engines we already have.
(Half of me is serious, and the other half is making a Key & Peele style "motherfucker that's called gasoline" joke.)
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You need green energy to produce climate friendly hydrogen. This is a LOT more inefficient than to just use that green energy directly in EVs. Thus green hydrogen is also expensive and most importantly it is needed in the industry. It's the same with e-fuels.
Hydrogen currently doesn't produce, store or transport well. This means it is not as economical as gasoline.
Not really a fan of lithium batts either. We're going to end up with some environmental problems down the line but its the most economically viable tech we have at present if we're intending on living the way we currently live.
As I understand it, the big issue is energy density? A tank of gasoline takes you quite far compared to an equivalent tank of hydrogen.
And don't get me wrong, lithium batteries are super bad at this too, but I do think that has been a limiting factor for H cars.
And then there's the whole tire dust issue which is definitely a conversation worth having.
Wdym super bad? Most new EVs go like 500km on a charge
Yeah, but they require somewhere in the neighborhood of a thousand pounds of batteries to do so. Some of the more egregious ones need multiple thousands, e.g. the electric hummer whose battery alone is heavier than an ICE Honda Civic. Whereas a dozen gallons of gasoline (roughly 72lbs at 6lb/gal) can power that same ICE Civic for a nearly equivalent range, while causing much less wear & tear on the roads, and likely releasing less tire particulates due to the reduced weight. Of course it still releases CO2 and other nasties...
But yeah, the energy density of EVs is still super bad. It's just "good enough" that we're making it work.
Production is wildly inefficient and the storage and transfer of the stuff is quite tricky.
Because right now we don't have that much excess energy... Therefore it's just a waste of energy to use it, because it is way less efficient. AND on top of it an hydrogen car also needs a battery just a smaller one. So it has all the downsides without any upsides. The only upside is that you can recharge your car faster and it has some more range. But both those things don't matter for the average consumer
It makes sense for long haul trucking and aviation vs batteries, at least for now, but it doesn't scale well for most common consumer vehicles. Any hydrogen vehicle needs to be a hybrid because there isn't the fine tune fuel ratio control you get on traditional gasoline.
I don't think any average person would know of these advantages. So theres a general lack of education about the topic.
There is also a hydrogen refueling network problem to overcome. Before public electric charging stations existed, electric people could charge at home and install their own chargers where required so the electric industry has been able to partially side step that issue at the beginning.
Finally I think it just doesn't seem sexy. To a casual bystander it's like gas in, pay, then drive as usual.
Hydrogen might get more prominent in the heavy vehicles, with few more innovation.
probably because of infrastructure. electric charging stations were one of the first around and if you ask a new car buyer to choose between two renewable fuel sources, they'll chose the one with the most stations. In the US at lease, hydrogen stations have always been few and far between, and often quite pricey.