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“Battery EV” vs “Hydrogen Fuel cell EV”
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tom66:

--- Quote from: Sal Ammoniac on November 15, 2021, 07:24:46 pm ---The CEO of Toyota is pushing internal combustion engines burning hydrogen as a carbon-neutral power source.

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The other problem is it's pretty difficult to make a hydrogen ICE car - I mean it's not as if hydrogen FCEVs are easy *either* but hydrogen ICE introduces even more complexities.



To make an efficient one, you basically have the same problem efficient, powerful diesels have: NOx.  So you won't be getting rid of adblue any time soon.  'tho I suppose you could produce the ammonia from excess hydrogen.

It's also even less efficient than hydrogen FCEV, because an ICE is just not that thermodynamically efficient.   The best fuel cells are ca. 75-80% efficient, with a motor, maybe 60-70% of hydrogen goes to the wheels;  an ICE is what, 33-40%?  I am not sure how hydrogen changes that efficiency, but we also have to remember that a FCEV gets you "hybrid" for free, that is, regen braking, electric A/C, electric PS, and no ICE running under inefficient acceleration/coast profiles.  Those usually only come if you then bolt an electric motor onto the side of an ICE engine, so you still need a small battery pack and inverter.

It's really hard to see what the Toyota CEO is thinking here - he's clearly betting on battery EVs being too expensive (despite the fact you can now get 50kWh battery cars like e-208 which aren't *that* much more expensive than their ICE counterpart) - but at the same time thinks that we're going to have massive amounts of hydrogen infrastructure and hydrogen fuel to throw about.  Obviously, because we'd be throwing away 5x as much renewable energy per km travelled with hydrogen ICE than a battery EV.

I do see a strong future for hydrogen, but I think it will be in domestic/industrial heating, air travel, trucks and for trains where they are impractical to otherwise electrify.  It just doesn't add up for passenger cars.
ogden:

--- Quote from: tom66 on November 15, 2021, 08:36:23 pm ---It's really hard to see what the Toyota CEO is thinking here - he's clearly betting on battery EVs being too expensive (despite the fact you can now get 50kWh battery cars like e-208 which aren't *that* much more expensive than their ICE counterpart) - but at the same time thinks that we're going to have massive amounts of hydrogen infrastructure and hydrogen fuel to throw about.  Obviously, because we'd be throwing away 5x as much renewable energy per km travelled with hydrogen ICE than a battery EV.

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Business as usual. In this case he is trying to convince petrolheads to buy hydrogen cars - to earn more :)
SiliconWizard:

--- Quote from: not1xor1 on November 15, 2021, 07:52:56 pm ---
--- Quote from: Sal Ammoniac on November 15, 2021, 07:24:46 pm ---The CEO of Toyota is pushing internal combustion engines burning hydrogen as a carbon-neutral power source.

https://www.bloomberg.com/news/articles/2021-11-13/japan-carmakers-showcase-carbon-neutral-fuels-in-road-race

To me, that's a step backwards from EVs and fuel-cell hydrogen cars. IC engines are inefficient (think of all of the waste heat they produce), and even when they're burning hydrogen they still produce NOx pollution that needs to be dealt with using a catalytic convertor.

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hydrogen is still produced from fossil fuels (methane). All that hydrogen stuff is pure nonsense. In the meantime they are building a factory for new DC motors made just of copper, i.e. no rare earth elements for permanent magnets while Na-ion batteries are already in production and you get plenty of Na from the oceans...

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Hydrogen production is absolutely nonsense at the moment from any efficiency or carbon-neutrality POV. But the whole point is that it can be - kinda - used as an almost direct replacement of classic fuels. The devil is in the details though, and the kinda is, in practice, kinda, but it makes the switch look easier than going for an EV, allows to reuse designs and patents - for the ICE approach in particular...

Everyone and their brother will jump on the hydrogen bandwagon these days. Doesn't mean it makes sense. Hydrogen is the new graphene.
TimFox:
If a "free" source of power should become practical (e.g., fusion), water could be electrolysed into hydrogen and oxygen at the power source and distributed through pipelines.  However, it is true that 95% of current industrial production of hydrogen is from natural gas, where the rest of the feedstock is carbon. 
See  https://en.wikipedia.org/wiki/Hydrogen_production
Sal Ammoniac:
That's the problem. Although hydrogen makes up 90% of the matter in the universe, on earth it's bound up in compounds that require lots of energy to create free hydrogen. The water in the oceans is a nearly unlimited source of hydrogen, but splitting it into oxygen and hydrogen by electrolysis requires 260 kJ/mole. Other methods, like treating methane with high temperature steam, has comparable energy costs and some of these techniques (like steam reforming of methane) produce CO2 as a byproduct.
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