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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

#431

Post by WalterBright »

Qwertious wrote: post #296
WalterBright wrote: post #169

Earlier quoted context omitted.

> So now we're only 3x-4x of a direct replacement. The math leads out an important factor. As the liquid fuel burns, the airplane gets lighter. A lot lighter. Less weight => more range. More like 6x-8x. Batteries don't get lighter when they discharge.

It's not that simple. Batteries are inherently more aerodynamic, because they don't need to suck in oxygen for combustion, and because they need less cooling than an engine that heats itself up by constantly burning fuel. You can getv incredible gains just by improving motor efficiency - the difference between a 98%-efficient motor and a 99%-efficient motor is the latter requires half the cooling . That's more import…

The fuel tanks are compartmentalized and have baffles to prevent sloshing. It's a solved problem.

Electric motors are not 98-99% efficient.

As you alluded to, battery weight is more than ICE weight. EVs are significantly heavier than ICEs.

I'm sure we can expect improvements along the lines you mentioned, but I seriously doubt it will be nearly enough.

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

#432

Post by WalterBright »

westmeal wrote: post #355
saalweachter wrote: post #278

Earlier quoted context omitted.

What if you just, like, put the hydrogen in a big balloon?

Dude so like, one time some guy did that and like the entire thing just blew up bro. Seriously knockered.

Hydrogen airships are unfairly demonized. Airplanes burn and blow up, too - we've just learned over time how to minimize that risk.

The main problem with an airship is they are vulnerable to weather.

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

#433

Post by closewith »

pfdietz wrote: post #425
closewith wrote: post #398

Earlier quoted context omitted.

It does, definitively.

If it does, then it also rules out long distance transmission of electrical power, as that is even more expensive. And the hydrogen advantage is even greater when one considers one can piggyback storage onto this system, as is done in natural gas pipelines. The electrical system would need additional batteries which are much more expensive per unit of storage capacity.

You are simply wrong on this. HVDC losses total ~5% for 1,000km, including step up and step down losses.

H2 will experience 20-30% over the same distance of natural gas line including compression and friction losses. DOA.

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

#434

Post by travisb »

bryanlarsen wrote: post #395
Manuel_D wrote: post #327

Earlier quoted context omitted.

Is suspect large trucks may eventually move to hydrogen, but smaller passenger vehicles will stay on batteries. The nature of hydrogen containment favors larger capacity, on account of better volume to surface area ratios.

Many jurisdictions require that commercial drivers take a 30 minute break every 4 hours. Those that don't should. Those stops make battery trucking feasible. And if you want to stop for 5 minutes instead of 30 you can use battery swapping solutions like the one Janus uses. Batteries are feasible for long distance trucking today. Green Hydrogen trucking uses 3X as much electricity as using it directly. Trucking's bigg…

Using mandated breaks for recharging heavy trucks isn't actually helpful in much of the world. Maybe it is in parts of Western Europe.

The problem is that those mandated breaks are mandated and happen (with a small amount of wiggle room) wherever the truck happens to be at that moment. Rolling out enough charging infrastructure to make that work is an even more immense challenge than the already massive challenge of adding sufficient charging infrastructure to places like existing truck stops.

Imagine the cost of installing 1MW chargers on, say, half the wide spots on every highway.

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

#435

Post by TheSpiceIsLife »

Shaanie wrote: post #410
TheSpiceIsLife wrote: post #399

Earlier quoted context omitted.

You’re going to have to explain how you read from what I wrote. From the site guidelines: Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith. https://news.ycombinator.com/newsguidelines.html

It's quite impressive to quote the guidelines to someone when your first post breaks a whole bunch of them.

[flagged]

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

#436

Post by TheSpiceIsLife »

antonvs wrote: post #337
TheSpiceIsLife wrote: post #324

Earlier quoted context omitted.

> Republican presidents have added about $1.4 trillion per four-year term, compared to $1.2 trillion added by Democrats since 1913. That doesn’t sound right, so I spend twenty three seconds looking it up: New Report Reveals Democrats Generated 90% of Federal Debt Held by the Public since WWII - https://www.jec.senate.gov/public/index.cfm/republicans/2011... As of April 5, 2024, the national debt has grown by about $6…

Your last source contradicts your first (partisan) source, and also mentions: > The national debt grew by more than $8.1 trillion during Donald Trump’s presidency, the largest four-year increase in the nation’s history.

I was addressing the claim that Democrats had added merely $1.2 trillion since 1913.

I apologise if that wasn’t clear enough.

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

#437

Post by whatever1 »

vel0city wrote: post #119
whatever1 wrote: post #84

Not that much worse than an ev.

Used models for my five year old EV are still selling for ~50% of what I paid for, so no, its far worse than most EVs.

Looking at Ford Mach-E. I don't see the number you are seeing. I can find 2024 Mach-E 50% off its MSRP.

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

#438

Post by mapontosevenths »

dredmorbius wrote: post #251
mapontosevenths wrote: post #182

Earlier quoted context omitted.

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 perfo…

I hadn't heard of Fischer-Tropsch. Looks like it usually works based on gassification of biomass or existing fossil fuels, so it seems at first glance that it has the same negative externalities as just burning the source material doesn't it?

The Sabatier process looks like it might have much less of that! Very cool stuff. I would love to see a future in which we use uninhabitable, non-arable, desert land to generate cheap synfuel that we can ship wherever needed.

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

#439

Post by Tade0 »

b112 wrote: post #351
Tade0 wrote: post #318

Earlier quoted context omitted.

> EVs take forever to charge, rendering long trips unrealistic. You'll find EVs that will go 700km+ with just one, 15min stop, as they charge at over 350kW in this day and age: https://ev-database.org/#group=vehicle-group&av-1=1&rs-pr=10... You'd want to make that 15min stop at least once on such a trip. Or fly instead. > It's only through trillions of research dollars, that current battery tech is where it is. Probl…

There is only one car in that database that has even close to a 700km range on long trips, and that is only under perfect conditions. As with any car, you don't wait until out of fuel to recharge. Instead, you seek to do so well before. These pages at least understand a little of that, and cite a real-world range under perfect conditions of 450km before recharging, with a range of 300km afterwards. Yet these figures…

> I often have circumstances where I drive 1600km a day.

Do you not do stops? The ranges I've shown include a 15min stop to recharge.

Anyway, I used to do such trips regularly. Covered over 100k km like that. I still did stops every ~400km because a man's gotta eat and, more importantly, wee.

Also sleep, because after a few close calls caused by 18h+ of driving I figured it makes more sense to find a hotel after 1200km or so.

Overall, current-day EVs and infrastructure wouldn't add more than 30min (if anything at all) compared to a combustion car if I were to do the same trip today.

In hindsight I should have flown and take taxis at my destination - would have been cheaper.

My view is that you're arguing about a non-issue, because the small minority that actually runs down a full tank before stopping is endangering others and being unkind to their bodies.

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

#440

Post by graemep »

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?

> 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?

The Mirai uses the hydrogen in a fuel cell so it is an EV: https://en.wikipedia.org/wiki/Toyota_Mirai

It looks like a reasonable idea, but it needs infrastructure.

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