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Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

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Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#101

Post by cbmuser »

Rygian wrote: post #92
ForHackernews wrote: post #88

Earlier quoted context omitted.

Why is it such a terrible idea? In theory you can generate it via electrolysis in places with plentiful renewable energy, and then you've got a very high-density, lightweight fuel. On the surface, it seems ideal for things like cars or planes where vehicle weight matters. Batteries are huge and heavy and nowhere near as energy dense as gasoline.

Check out the "Clean Hydrogen Ladder" document. Hydrogen wastes a large amount of energy.

Unless you produce it using the Sulfur-Iodine cycle in a high-temperature nuclear reactor.

See: https://en.wikipedia.org/wiki/Sulfur%E2%80%93iodine_cycle

and: https://www.jaea.go.jp/04/o-arai/nhc/en/research/hydrogen_he...

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#103

Post by SideburnsOfDoom »

SilverElfin wrote: post #44

I still feel hydrogen fuel cells are the better choice. The convenience of refilling quickly is great. Maybe that’ll matter less if PHEVs are allowed to exist but with some places banning gas cars entirely, I don’t have hope.

> The convenience of refilling quickly is great.

Is it more convenient than plugging in an EV overnight at home, and having a full "tank" every morning?

It is not.

Electricity supply is everywhere. More so than Gasoline supply, and far far more so than hydrogen supply.

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#104

Post by cbmuser »

BadBadJellyBean wrote: post #10

I don't think hydrogen will ever be a thing for personal cars. Apart from the abysmal "well to wheel" efficiency it's also just such a hassle to create a fuel network for it. Gasoline is bad enough but a gas that will just leak away whatever you do seems like a stretch. It is just so much simpler with electricity. Pretty much every gas station already has it. No driving it around with trucks. Just maybe once install…

> It is just so much simpler with electricity.

Yet the market still thinks differently. Lots of countries still keep subsidizing EV despite them already being mature technology for such a long time.

We didn't have to subsidize the smart phone to make it successful, we shouldn't have to subsidize electric cars either.

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#105

Post by oceanplexian »

If you think depreciation on a few cars is bad wait until you find out how many hundreds of millions taxpayers spent to build hydrogen stations for cars that don’t exist.

At least it’s not as blatant of a green energy scam as the high speed rail to nowhere. In this case they actually built a few stations that worked.

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#106

Post by L-four »

ForHackernews wrote: post #88
aunty_helen wrote: post #60

Kinda glad this is the case. When people go out of their way to avoid common sense they should be punished. Hydrogen is such a terrible idea it was never getting off the ground. There seems to be some kind of psychosis around it being the next oil and therefore greedy people want to get in early on. But this blinds them to the basic chemistry and physics.

Why is it such a terrible idea? In theory you can generate it via electrolysis in places with plentiful renewable energy, and then you've got a very high-density, lightweight fuel. On the surface, it seems ideal for things like cars or planes where vehicle weight matters. Batteries are huge and heavy and nowhere near as energy dense as gasoline.

The cheapest way to make hydrogen is to use fossil fuels.

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#107

Post by smcin »

CamperBob2 wrote: post #90
ForHackernews wrote: post #88

Earlier quoted context omitted.

Why is it such a terrible idea? In theory you can generate it via electrolysis in places with plentiful renewable energy, and then you've got a very high-density, lightweight fuel. On the surface, it seems ideal for things like cars or planes where vehicle weight matters. Batteries are huge and heavy and nowhere near as energy dense as gasoline.

Besides being expensive to generate unless you already happen to have an electrolysis plant handy, hydrogen is awkward and hazardous to store. Once generated, it costs yet more energy to liquefy, and then it seeps right through many common metals, weakening them in the process. It's just not a good consumer-level energy source, and nobody could figure out why Toyota couldn't see that. Interestingly, liquid hydrogen i…

Remember that China briefly embargoed Japan for rare earth metals in 2010, and Toyota launched the Mirai in 2014. My theory was that it was developed as a national fallback for Japan in case that embargo continued or got worse. Think 1930s Volkswagen. Anyone can comment on that?

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#108

Post by loeg »

ForHackernews wrote: post #88
aunty_helen wrote: post #60

Kinda glad this is the case. When people go out of their way to avoid common sense they should be punished. Hydrogen is such a terrible idea it was never getting off the ground. There seems to be some kind of psychosis around it being the next oil and therefore greedy people want to get in early on. But this blinds them to the basic chemistry and physics.

Why is it such a terrible idea? In theory you can generate it via electrolysis in places with plentiful renewable energy, and then you've got a very high-density, lightweight fuel. On the surface, it seems ideal for things like cars or planes where vehicle weight matters. Batteries are huge and heavy and nowhere near as energy dense as gasoline.

It's hell to store. The energy density is terrible and as a tiny molecule it escapes most seals. When it transitions from a liquid to a gas, it expands manyfold (i.e., explodes).

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#109

Post by credit_guy »

stephen_g wrote: post #91
ForHackernews wrote: post #88

Earlier quoted context omitted.

Why is it such a terrible idea? In theory you can generate it via electrolysis in places with plentiful renewable energy, and then you've got a very high-density, lightweight fuel. On the surface, it seems ideal for things like cars or planes where vehicle weight matters. Batteries are huge and heavy and nowhere near as energy dense as gasoline.

It’s horrible to work with - dangerous, embrittlement issues etc., and very energy intensive to compress into very heavy cryogenic storage containers…

> dangerous

It is actually less dangerous than other fuels, for the simple reason that it is extremely light and buoyant. A gasoline fire is bad, because the gasoline stays where it is until it fully burns. A hydrogen fire is less bad, because it will tend to move upwards.

Re: Toyota’s hydrogen-powered Mirai has experienced rapid depreciation

#110

Post by newyankee »

empathy_m wrote: post #76

At one point recently the Mirai came with a fuel incentive program: when you buy the car, Toyota gives you a gift card worth $15,000 towards fuel at hydrogen stations. An interesting second part of the program was that if you live near a hydrogen station but it's broken, Toyota will instead reimburse a rental car and gas for the rental, one week at a time but presumably for as long the hydrogen fuel station remains b…

I think a few people were expecting the same cost curves that happened with batteries to happen with hydrogen but it seems the challenges are more difficult to overcome. Otherwise I think a Solar PV plant combined with Captive hydrogen production for refuelling on major highways sounds interesting, at least in countries like US, Australia etc. I believe this is not just about PEM or AEM electrolyser or specific tech, it never got the scaling boost.

Ironically the stack comprising fuel cells of different types is possibly very well studied since decades.

For me the Wells to wheel efficiency never made hydrogen worthwhile for short to medium distances and this battle is effectively over.

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