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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

#251

Post by dredmorbius »

mapontosevenths wrote: post #182
nandomrumber wrote: post #123

Earlier quoted context omitted.

There is a great way to store, transport, and use hydrogen: Bind it to various length carbon chains. When burned as an energy source the two main byproducts are carbon dioxide which is an essential plant growth nutrient, and water which is also essential to plant growth. Environmentalists will love it! And they can prise my turbo diesel engines from my cold dead hands.

Carbon Dioxide is a greenhouse gas, which makes the world warmer on average. It also lowers the PH levels of the oceans. If the oceans die, its very likely that many or even most humans will also. As a human I am pretty strongly opposed to dying, but thats just, like, my opinion man.

It's possible to synthesise hydrocarbon analogues of petroluem-based fuels. The problem to date has been that this isn't cost-competitive with petroleum, though the difference is narrower than you might expect. Most famously, a Google X Project attempted this and succeeded technically, but the economics were unfavourable: Project Foghorn: https://x.company/projects/foghorn/>. Both Germany and South Africa have performed synfuel production (from coal) at industrial scale since the 1930s / 1950s, respectively. Using non-fossil carbon is largely the same chemistry; the process does in fact scale.

Fischer-Tropsch and Sabatier process can both operate with scavenged CO2. There's been some work since the 1990s utilising seawater as a CO2 source, with CO2 capture being far more efficient than from atmospheric sources.

Whilst hydrocarbons have numerous downsides (whether sourced from fossil or renewable sources), they are also quite convenient, exceedingly well-proven, and tremendously useful. In some applications, particularly marine and aviation transport, there are few if any viable alternatives.

I've commented on this numerous times at HN over the years: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...>.

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

#252

Post by mapontosevenths »

Timon3 wrote: post #220
nandomrumber wrote: post #218

Earlier quoted context omitted.

No one ever attract public support and funding by saying: Don’t Panic. Everything is O.K. —- Edited to add: Rate limited so can’t reply without creating more alt accounts than I’m willing to, so: @Timon3 - that’s actually a really good point, and I follow at least a few folk that could be categorised as such at least some of the time.

No, many people say exactly that and make a lot of money doing so while also telling us that all the evidence is fake.

Trump asked for a billion. [0] He didn't get the whole billion (as far as we know), but he's keeping up his end of the deal.

[0] https://www.politico.com/news/2024/05/09/trump-asks-oil-exec...

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

#253

Post by TheSpiceIsLife »

mapontosevenths wrote: post #217
TheSpiceIsLife wrote: post #184

Earlier quoted context omitted.

Take The Great Barrier Reef for example. There’s more of it now than in the reefs recorded history. Well, 2022 data: https://www.aims.gov.au/information-centre/news-and-stories/...

Bad news, there has been a fourth great bleaching event going on since January of 23. This time 80+% of all reefs have been impacted and the consensus seems to be that its unlikely there will be any reefs left at all before too long. https://www.theguardian.com/environment/2025/oct/13/coral-re...

[flagged]

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

#255

Post by overfeed »

dotancohen wrote: post #249
belorn wrote: post #203

Earlier quoted context omitted.

People looked at how the cost of wind and solar went down and made a assumption that green hydrogen would follow. The reasoning was that the cost of green hydrogen was energy, and thus at some point green hydrogen would be too cheap to meter. The whole energy plan of central/northen Europe, especially Germany, was built for the last several decades on the idea that they would combine wind, solar and cheap natural gas…

I had to Google what is green hydrogen. It is hydrogen produced by electrolysis. If you've already got the electricity for electrolysis, would it not be more efficient and mechanically simpler to store it in a battery and power an electric motor?

Before the introduction of 800V charging architectures, long charge-time for EVs was a big con. Hydrogen Cell vehicles were supposed to be EVs with drastically faster fill-up times. The tradeoff was more complex delivery infrastructure.

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

#256

Post by Intermernet »

TheSpiceIsLife wrote: post #253
mapontosevenths wrote: post #217

Earlier quoted context omitted.

Bad news, there has been a fourth great bleaching event going on since January of 23. This time 80+% of all reefs have been impacted and the consensus seems to be that its unlikely there will be any reefs left at all before too long. https://www.theguardian.com/environment/2025/oct/13/coral-re...

[flagged]

I think you've been listening to the wrong people. That's a whole lot of dog whistles in that screed.

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

#257

Post by MagicMoonlight »

thrownthatway wrote: post #230
aunty_helen wrote: post #181

Earlier quoted context omitted.

Even if it was fully green, you can’t run an electrolysis system from home. So you have to buy it, so there’s a market and an expensive solution. Electricity comes out the wall.

What do you mean? You can run electrolysis from a cup.

You can’t make and store bulk hydrogen at home

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

#258

Post by somat »

dotancohen wrote: post #249
belorn wrote: post #203

Earlier quoted context omitted.

People looked at how the cost of wind and solar went down and made a assumption that green hydrogen would follow. The reasoning was that the cost of green hydrogen was energy, and thus at some point green hydrogen would be too cheap to meter. The whole energy plan of central/northen Europe, especially Germany, was built for the last several decades on the idea that they would combine wind, solar and cheap natural gas…

I had to Google what is green hydrogen. It is hydrogen produced by electrolysis. If you've already got the electricity for electrolysis, would it not be more efficient and mechanically simpler to store it in a battery and power an electric motor?

I think that is the way it is headed. But you never know. Sometimes when comparing it helps me to reduce these things down to lower levels.

What is a battery? A chemical cell to store hydrogen and oxygen(true, it does not "have" to be hydrogen and oxygen but it usually is) to later get energy out of. For example lead-acid(stores the oxygen in the lead-sulfate plates and the hydrogen the the sulfuric acid liquid) or nickle-metal(charges into separate oxygen and hydrogen compounds, discharges into water) the lithium cell replaces hydrogen with lithium. Consider a pure hydrogen, oxygen fuel-cell, it could be run in reverse(charged) to get the hydrogen and oxygen and run forward(discharged) to get electricity out of it. So it is a sort of battery, a gas battery. Gas batteries are generally a bad idea, mainly because they have to be so big. Much time and effort is spent finding liquids that can undergo the oxidation/reduction reactions at a reasonable temperature. But now consider that there is quite a bit of oxygen in the air, if we did not have to store the oxygen our battery could be much more efficient, This is the theory behind free-air batteries. But what if our battery did not have to run at a reasonable temperature. We could then use a heat engine to get the energy out. And thus the Mirai. They are shipping half of the charged fluid to run in a high temperature reaction with the other half(atmospheric oxygen) to drive a heat engine that provides motive power.

As opposed to having the customer run the full chemical plant to charge and store the charged fluids to run in a fuel cell to turn a electric motor for motive power. Honestly they are both insane in their own way. But shipping high energy fluids tend to have better energy density. Perhaps the greatest problem in this case is that it is in gaseous form(not very dense) so has no real advantage. Unfortunately one of the best ways to retain hydrogen in a liquid form is carbon.

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

#259

Post by itishappy »

TheSpiceIsLife wrote: post #253
mapontosevenths wrote: post #217

Earlier quoted context omitted.

Bad news, there has been a fourth great bleaching event going on since January of 23. This time 80+% of all reefs have been impacted and the consensus seems to be that its unlikely there will be any reefs left at all before too long. https://www.theguardian.com/environment/2025/oct/13/coral-re...

[flagged]

Yes yes, The Sky Is Falling™. :)

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

#260

Post by aunty_helen »

HPsquared wrote: post #248
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.

Synthetic fuels (including hydrogen) do still make a lot of sense for heavy stuff like trucks, buses or trains, and aircraft where the energy density is a big plus. Those are where you'd expect to see hydrogen take off first, not passenger cars. Same as how diesel started in trucks - expensive engines but economical when amortized and worth it for heavy usage applications. If they couldn't crack those areas, no chanc…

Trucks and busses would be better off with battery swaps at depo like electric forklifts do. More mileage more towing weight for trucks, just stack more batteries. Overweight? Use a diesel.

Trains is an easy one, over head lines.

Aircraft, I think short distance trips <1hr maybe otherwise biofuel. Likely we’ll see biofuels widely used by 2040. Electric motors on a 777, I’m not sure.

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