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> Hydrogen is such a terrible idea it was never getting off the ground.

It's coming from Toyota because Toyota can't wrap its head around not making engines. Ironically, the place hydrogen might work is airplanes where the energy density of batteries doesn't work.



> the place hydrogen might work is airplanes where the energy density of batteries doesn't work.

How is that going to work? Cryogenic liquid hydrogen? High pressure tanks? Those don't seem practical for an airplane.

What does work for airplanes is to use carbon atoms that hydrogen atoms can attach to. Then, it becomes a liquid that can easily be stored at room temperature in lightweight tanks. Very high energy density, and energy per weight!

(I think it's called kerosene.)


Diesel, kerosene, rocket propelled RP1, and fuel oil / bunker fuel in the case of cargo ships.

It’s not a coincidence that where easy of handling, storage safety, and high energy density are needed everything seems to converge on compression ignition medium to long chain liquid hydrocarbons.


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.


Has the hydrogen storage problem been solved yet?

Last time I checked it needs to be stored in cryo / pressure vessel and it also leaks through steel and ruins its structural properties in the process.


There are some innovation like hydrogen paste but it’s not going to be useful for a combustion engine cycle.


The Mirai does not combust hydrogen.


We store hydrogen all the time for industrial processes. It's not some super science, it's just expensive.


We do? Where? Using what fabrication technologies.

I’ve worked mostly in or adjacent to manufacturing and primary industry.

As far as I’m aware, the majority of hydrogen production is use on site, and mostly for ammonia production.

There isn’t really much in the way of hydrogen storage and transportation, it’s mostly used where it’s generated.

And if we use expensive as a proxy for heavy / energy intensive, which it is in the case of hydrogen, that goes a long way to preclude it from anything like being useful for transportation.


There is hydrogen all over the place in exactly where you'd expect to see it: petroleum refineries and petrochemical process plants. The metallurgy of handling and storing hydrogen is well understood and has been for a long time. You just have to use alloys resistant to hydrogen embrittlement. Hydrogen is squirrelly - it doesn't like to stay put but you can make it stay put long enough to make it useful.

When you are specifying valving or piping in a refinery one of the big things you have to find out is how much hydrogen is in the process because a lot of stuff in a refinery has at least some hydrogen and it will destroy common alloys.


> Has the hydrogen storage problem been solved yet?

No. Not for using Hydrogen for transportation. People have been trying to use Hydrogen for transportation for more than 50 years. These people are trying to bend the laws of physics. And there are a lot of con artists in the mix who prey on the gullible. See the convicted fraudster Trevor Milton of Nikola fame.


WTF , you are commenting about FCEV - these things dont have engines!

The strategy clearly stated by Akio Toyoda is multiple power train technology. You can listen to his interviews on the subject, some are in Japanese, but as you have stated a clear and unambiguous interpretation of Toyota's policy I will assume you have that fluency.

(Automotive OEMs are assemblers, the parts come from the supply chain starting with Tier 1 suppliers. In that sense TMC does not do "making engines", but possibly the nuance and consequences here of whether not it "wraps it's head" to "makes things", vs if it has the capability to specify, manufacture distribute something at scale with a globally localized supply chain AND adjust to consumer demand/resource availability changes 5 years after the design start - in this context i ask you, can you "wrap your head" around the latest models that are coming out in every power train technology fcev, (p)hev to bev)


Toyota has had this hydrogen bug since the early 90's.

What's that old meme?

Stop trying to make ____ happen, it's not going to happen.


The point I was trying to make was I'm not sure it was ever about making something happen completely, but being prepared on all fronts for whatever the outcome is.

Kaizen and JIT are not good for revolutionary change. So I expect by bootstrapping different options early enough they can act on real market pressure once the condition to accurately assess the evidence is available.

For hydrogen getting to that point was a multi decade lead time.

I suspect most western commentary on this topic comes from people not understanding both how numerical/empirical based Toyota are, how self aware of their potential weaknesses they are, plus the ability of a Japanese business to hold to a multi decade hedging initiative.


Biofuel makes more sense for airplanes. No conversion even necessary. You could fuel up a 737 with properly formulated biofuel and fly it now, though a lot of validation would be needed to be generally allowed especially for passenger flights.

If we want easier to produce biofuels then LNG aviation makes sense. We are flying LNG rockets already. You could go ahead and design LNG planes now and they’d emit less carbon even on fossil natural gas. Existing turbofan jet engines could be retrofitted to burn methane.

Biogas is incredibly easy to make to the point that there are pretty easy designs online for off grid biogas digesters you can use to run a generator. You can literally just turn a barrel upside down in a slightly larger barrel full of water, shit, and food waste, attach a hose to it, and as the inner barrel floats up it fills with biogas under mild pressure that you can plug right into things. May need to dry it for some applications since it might contain some water vapor but that’s not hard.

Industrial scale biogas is basically the same principle. Just large scale, usually using sewage and farm waste.

LNG rockets also mean “green” space launch is entirely possible.


LNG aviation does not make any more sense than H2 aviation. Even LPG does not make any sense since you neither can haul 16 bar fuel tanks, nor can you realistically maintain temperature for 1-2atm pressure. And any leak is not 'oh. look, a kerosene stain on tarmac', it's ready-made fuel-air explosion.

On the plus side we would be able to retire airport fire engines because they would never be able to get to a crash before it completely burns out.


You can't get much better than ready-made, for rocketry.

As if LNG is effectively more dense in flight than ordinary LPG, which doesn't need to be cryogenic to handle.

Armchair fuel experts do still provide food for thought though ;)


> It's coming from Toyota because Toyota can't wrap its head around not making engines.

Of course they can. Toyota sells BEVs. As time goes on BEVs will become a greater percentage of their sales.


The bZ4X? 10+ years after the Nissan Leaf?


And the bZ3, bZ5, bZ7, bZ3X, bZ Woodland, C-HR+, the Lexus RZ, and soon the Hilux EV:

https://electrek.co/2026/01/09/toyota-electric-pickup-images...


A list of cars that aren't available for purchase yet doesn't disprove the argument that Toyota is late to the game.


They are available for purchase.

Toyota is in the game of selling cars. Toyota has been the best selling automaker for the last six years straight.

Toyota had record sales last year:

https://www.reuters.com/business/autos-transportation/toyota...

It's possible that Toyota understands the car business better than you do.


All of the bz* models you listed are Chinese models, and while the Woodland and C-HR are listed on their US website, they aren't really available for purchase (though I did find one C-HR if I'm willing to drive 500 miles to buy it). Obviously the world auto market is greater than the US, but the US is the leading market for Toyota in terms of total units sold, so it's odd to me that if I drive to the Toyota dealership 10 minutes from my house, their game of selling cars only leaves me with one model to purchase if I'm committed to buying a BEV.


China is the biggest EV market, Europe is the second biggest, and North America is third.

For EVs the US will remain lower priority than China and Europe for a while yet. Toyota understands how to sell cars.

It's funny how this thread has gone from "Toyota can't wrap its head around not making engines" to "Toyota is not prioritizing small EV markets first".


You are correct that China is the number one market in terms of BEV sales, but the US is number two, selling more than 3-5 combined. That's an odd way to define a small EV market. Funny thing is, in terms of rankings, the US is actually a "small market" when it comes to gas-only cars.

Prior to moving to only BEVs, our family bought several Toyotas (and before that, only Hondas), and I was disappointed to find that I had no options (at the time, and in the 4 years since, between the 2 manufacturers, only 2 have come to market that I can purchase). Perhaps VW and Kia don't understand how to sell cars, but they understood how to sell them to me.


> You are correct that China is the number one market in terms of BEV sales, but the US is number two, selling more than 3-5 combined.

This is incorrect, unless you're viewing the US as a single market but the EU as multiple (which, I mean, ah, you do you, but that doesn't make any sense from an industry perspective). Last year about 1.3 million BEVs were sold in the US (a minor decline from 2024), 1.9 million BEVs were sold in the EU (up 33% YoY). In Europe more broadly defined, 2.5 million BEVs were sold (in practice, the industry largely treats EU+EFTA+UK as one market). In China, 8 million were sold, up about 25% YoY.

You can, ah, perhaps see why the US is not a top-priority market for the industry. In practice, the US _will_ get many of these Toyota models, or some variant thereof, but later. You mention VW, but they, too, treat the US as a second priority BEV market; their electric cars generally come out about a year late there if at all. Hyundai does release in the US at the same time as elsewhere (when they release at all; the Ioniq 3 will not be available in the US, for instance, because the US does not buy small cars in significant numbers).


Nation-based segmentation makes the most sense to me because as I understand it (coming from a US-centric perspective, so I may have misunderstandings) there may be additional friction (fees, regulations, etc) buying from another EU country as opposed to someone in the US buying a vehicle from a different state. In many cases, you don't even have to go to another state; dealerships regularly transfer inventory (with a shipping fee, but not anything at the government level)


The entire point of the European Union is to eliminate all of that friction. Most of the rules and regulations have been pushed to the EU level, just like the USA pushed most of its rules and regulations to the federal level. A car only needs a single type approval granted by a single member state, and it can be sold across the entire EU.

There are of course still some tax differences and importing from another member state might be slightly trickier for a consumer than buying it from a dealership in their own country, but I don't see how that is any different from dealing with different kinds of sales tax in the various US states, or having to transfer your car title to another state.

The European single market operates as, well, a single market.


From the point of view of the manufacturers, the Single Market is, ah, a single market; they only have to get type approval once, and then they can sell anywhere. The only real complicating factor is Ireland and Malta, which drive on the left side of the road (and some niche cars will never be released there as a consequence; for instance Tesla stopped selling Model S/X in a left hand drive configuration a while back, though they now seem to have stopped selling both in Europe entirely, in any case).

Post-Brexit, the UK has its own type certification (and of course it also has the left hand drive problem), and, again, some niche car models may be available in the EU but not the UK. But in practice, for mainstream stuff, the manufacturers tend to treat it as just part of the European market.



Toyota sells bad EVs and was the last OEM to offer one. It’s the most anti-EV OEM by far and engages/engaged in the most EV FUD.


The bZ4X was particularly bad. Toyota adopted a combo of NIH syndrome and DNGAF. They didn’t anticipate cold weather. The batteries lost like 30% of their capacity in the cold and the resale value of it tanked.


> The batteries lost like 30% of their capacity in the cold

Here in Norway Toyota was invited to include the bZ4X in this years winter range test[1], but they declined. Suzuki entered with their eVitara model, which is a "technological twin" of the Toyota Urban Cruiser.

The Urban Cruiser really disappointed in a regular test performed in cold weather[2]. So perhaps unsurprisingly, the Suzuki eVitara was by far the worst in the winter range test, with the least range overall and more than 40% reduction compared to its WLTP range, among the worst in the test.

[1]: https://www.tek.no/nyheter/nyhet/i/d4mMkA/verdens-stoerste-r...

[2]: https://www.tek.no/test/i/OkQAwE/toyota-urban-cruiser


They’re also just phenomenally ugly cars.


It shares the same ugly design language as much of Toyota’s lineup.


> Toyota sells bad EVs

The 2026 bZ Woodland [1] looks pretty nice in my opinion.

[1] https://arstechnica.com/cars/2026/02/looks-a-lot-like-an-ele...


I have only purchased Toyota vehicles (currently in the market for an EV) and it baffles me that Dodge created a Charger in EV form and Toyota hasn’t made even an EV Corolla or Camry.


> it baffles me that Dodge created a Charger in EV form and Toyota hasn’t made even an EV Corolla or Camry

Dodge's Charger EV has been a sales flop [1] and pretty much universally panned by critics as something that nobody asked for.

The Camry and Corolla were the best-selling sedan and compact sedan of 2025 [2]. I think this shows that Toyota is listening to what Corolla and Camry drivers want - something inexpensive and reliable to get them to and from work every day without issue.

Some day Toyota will make an EV sedan. I think their 2026 bZ Woodland [3] shows that they are starting to figure out how make compelling EVs. And Toyota's EV strategy seems pretty reasonable to me overall - their delays to develop a decent EV don't seem to put them under threat from any legacy automakers. They are being threatened by Chinese EV makers, but so is Tesla - so even a huge head start likely wouldn't have benefited Toyota much either in that regard.

[1] https://www.roadandtrack.com/news/a69927938/dodge-charger-da...

[2] https://www.caranddriver.com/news/g64457986/bestselling-cars...

[3] https://arstechnica.com/cars/2026/02/looks-a-lot-like-an-ele...


An electric Corolla or Camry is my ultimate. I hate driving.

I want an appliance that just works. The Corolla and Camry were this for petrol.

I love my Leaf but it isn’t a Carolla.

What’s with the turning circle on the Leaf?


That's essentially the bZ3. But a Corolla branded BEV will eventually happen:

https://electrek.co/2025/10/13/toyotas-best-selling-car-elec...


And yet they had one of the first hybrids (although not a plug-in hybrid) in the Prius.


Honda also was early in hybrids, but they like Toyota are also late on EVs.


The difference is probably philosophical. A (non-phev) hybrid is primarily an ICE car in every way. Building hybrids is building ICE cars with a little extra. Building EVs is different.


Honda and Toyota invested a lot in hybrid tech, they probably want to milk that investment more and the hydrogen distraction kept them from also investing in BEV tech. China was basically starting a car industry from scratch so didn’t have those sunk costs to worry about.


We're actually not that far off.

Right now, liquid fuels have about 10x the energy density of batteries. Which absolutely kills it for anything outside of extreme short hop flights. But electric engines are about 3x more efficient than liquid fuel engines. So now we're only 3x-4x of a direct replacement.

That means we are not hugely far off. Boeing's next major plane won't run on batteries, but the one afterwards definitely will.


> 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 getvincredible 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 important than the ~1% increase in mileage.

Also, the batteries are static weight, which isn't as nightmarish as liquid fuel that wants to slosh around in the exact directions you want it not to. Static weight means that batteries can be potentially load-bearing structural parts (and in fact already are, in some EV cars).

The math leaves out a lot of important factors.


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.


Not to mention that jet planes routinely take off heavier than their max safe landing weight today too, relying on the weight reduction of consuming the fuel to return the plane to a safe landing weight again while enjoying the extra range afforded. This trick doesn't work well with batteries either.


There isn't any battery technology on the horizon that would lead to practical airliners.


You could do it with a ground effect plane for inland sea jaunts, like Seattle to Victoria. If you can float, then you don’t technically need a huge reserve like is normally needed.


> Boeing's next major plane won't run on batteries, but the one afterwards definitely will.

Jet engines work better. Boeing's next major plane will have jet engines, just like their previous major planes.

Synthetic, carbon neutral jet fuel will be the future for commercial jets.


Well, there's also burning regular fuel in a fuel cell, a FCEV. That doubles the efficiencies over ICE, so I guess that bumps it back up to 8x away?

Given the great energy densities and stability in transport of hydrocarbons, there's already some plants out there synthesising them directly from green sources, so that could be a solution if we don't manage to increase battery densities by another order of magnitude.


> there's already some plants out there synthesising them directly from green sources

I didn't realize that a "green" carbon atom is different from a regular carbon atom. They both result in CO2 when burned.


The problem isn't CO2 it's pulling carbon out of geological deposits. Thus the carbon atoms in synthetic fuel can be considered "green" provided an appropriate energy source was used.


I understand that, but it's a fallacious argument. It's still emitting the same amount of CO2 into the atmosphere.

You can also bury dead trees in a landfill.


You misunderstand the problem. The act of emitting CO2 into the atmosphere is not a problem.

Significantly increasing the CO2 concentration in the atmosphere is the problem. This happens when geological sources are used.

Unfortunately, burying dead trees in a landfill doesn't solve the problem because they decompose to methane which escapes. But you're right that geological CO2 production could be balanced by geologic CO2 sequestration, done properly.


The point is that emitting CO2 into the atmosphere was never the problem. Adding geological carbon back into the carbon cycle is the root cause of the entire thing.

You can certainly bury dead trees. I'm not sure how deep you'd need to go to accomplish long term (ie geological timeframe) capture. I somehow doubt the economics work out since what is all the carbon capture research even about given that we could just be dumping bamboo chips into landfills?


> I'm not sure how deep you'd need to go to accomplish long term (ie geological timeframe) capture.

Coal mines are sequestered trees.


Correct, but burying trees today isn't going to turn them into coal.

The big difference is that when the current coal layers were formed, bacteria to decompose trees hadn't evolved yet. There was a huge gap between trees forming and the ecosystem to break down trees forming, which led to a lot of trees dying and nothing being able to clean it up, which meant it was just left lying there until it was buried by soil and eventually turned into coal.

Try to bury a tree today, and nature will rapidly break it down. It won't form coal because there's nothing left to form coal.


But if the CO2 recently came from the atmosphere it's still a net zero impact though.

Like, take 5 units of carbon out of the atmosphere to create the fuel. Burn it and release 5 units of carbon to the atmosphere. What's the net increase again? (-5) + 5 = ?

FWIW I'm not saying these processes actually achieve this in reality. Just pointing out that it could be carbon neutral in the end.


> I didn't realize that a "green" carbon atom is different from a regular carbon atom.

Easy mistake to make, don't beat yourself up over it.

It's not the individual carbon atoms that carry the signature, it's the atoms in bulk that give the story ... eg: 6 x 10^23 carbon atoms

See: https://pmc.ncbi.nlm.nih.gov/articles/PMC7757245/


Its the time shift. Burning a plant releases CO2 and it is still considered to be carbon neutral.


Sorry, that's just verbal sleight of hand. There's no such thing as "green" CO2.


Yes there is. I used to fall for the same lie, but it's just not true. It's a question of system boundaries.

Green CO2 was recently (in geological terms) captured from the atmosphere into biomass, that's why its release is basically net zero.

Fossil CO2 hasn't been part of the atmosphere in eons (back in e.g. the Crustacean, the CO2 ratio was many times higher), so its release is additive.


So bury the trees. Or run them through the sawmill and build houses.


How do you justify exhaling then?


Well, you don't. Everything you do has a carbon footprint, you know, haven't you heard? Everything.


Have you always had difficulty with abstraction?


And, the two major byproducts of burning hydrocarbons are water and carbon dioxide.

Literally essential plant nutrients, essential for life.

Tangentially related, the 2022 Hunga Tonga–Hunga Haʻapai volcanic eruption ejected so much water vapour in to the upper atmosphere, it was estimated to have ongoing climate forcing effects for up to 10 years.

Water vapour is a stronger greenhouse gas than carbon dioxide.

And we heard precisely nothing about that in the media other than some science specific sources at the time and nothing on an ongoing basis.

From Wikipedia:

The underwater explosion also sent 146 million tons of water from the South Pacific Ocean into the stratosphere. The amount of water vapor ejected was 10 percent of the stratosphere's typical stock. It was enough to temporarily warm the surface of Earth. It is estimated that an excess of water vapour should remain for 5–10 years.

https://en.wikipedia.org/wiki/2022_Hunga_Tonga%E2%80%93Hunga...


Please, the media didn't report on this because natural disasters affecting the climate is not controllable by humans and thus doesn't warrant a global effort to address unless it's so large as to be species ending.

Global warming is not fake, there's tons and tons of evidence it is real and the weather is getting more and more extreme as humans continue to burn petrol.


Also some time after that other guy copied and pasted his canned Hunga remark into his big spreadsheet of climate denial comments the international community of climate scientists concluded that Hunga cooled the atmosphere, on balance.

"As a consequence of the negative TOA RF, the Hunga eruption is estimated to have decreased global surface air temperature by about 0.05 K during 2022-2023; due to larger interannual variability, this temperature change cannot be observed."

https://juser.fz-juelich.de/record/1049154/files/Hunga_APARC...


Thanks for linking that document, I’ll have a read.


Yes, and it doesn’t fit the narrative.

We should be moving towards being able to terraform Earth not because of anthropogenic climate forcing, but because one volcano or one space rock could render our atmosphere overnight rather uncomfortable.

You won’t find the Swedish Doom Goblin saying anything about that.

> burn petrol.

Well yeah, so making electricity unreliable and expensive, and the end-user’s problem (residential roof-top solar) is somehow supposed help?

Let’s ship all our raw minerals and move all our manufacturing overseas to counties that care less about environmental impacts and have dirtier electricity, then ship the final products back, all using the dirties bunker fuel there is.

How is that supposed to help?

I mean, I used to work for The Wilderness Society in South Australia, now I live in Tasmania and am a card carrying One Nation member.

Because I’m not a complete fucking idiot.

Wait till you learn about the nepotism going on with the proposed Bell Bay Windfarm and Cimitiere Plains Solar projects.

I’m all for sensible energy project development, but there’s only so much corruption I’m willing to sit back and watch.

With the amount of gas, coal, and uraniam Australia has, it should be a manufacturing powerhouse, and host a huge itinerant worker population with pathways to residency / citizenship, drawn from the handful of countries that built this country. And citizens could receive a monthly stipend as their share of the enormous wealth the country should be generating.

Japan resells our LNG at a profit. Our government is an embarrassment.


Natural resources are not required to make a country an economic powerhouse. See Japan, for example. Hong Kong, Taiwan, S Korea.

What's needed are free markets. Any country that wants to become a powerhouse has it within their grasp. Free markets.


And political will.

The Antipodes have such a problem with successful people we even invented a term for it.

https://en.wikipedia.org/wiki/Tall_poppy_syndrome

On the subject of free markets, Australia excels. We even let foreign entities extract and sell our LNG and pay no royalties and no tax.

https://australiainstitute.org.au/post/zero-royalties-charge...

Doesn’t get any freer than that!


Spain stripped S. America of its gold and silver, and neither Spain nor S. America benefited from it.


Doesn’t South America collectively produce more gold in one year than the Spanish usurped from them in their entire conquest period?

Gold production by country:

https://en.wikipedia.org/wiki/Lists_of_countries_by_mineral_...

In only the first half-century or so of the Spanish conquest of the Americas, over 100 tons of gold were extracted from the continent. - https://www.worldhistory.org/article/2045/the-gold-of-the-co...

Context is for kings though. In the context of what occurred when it occurred, you’re right.

For a while there, Australia was known as ‘the lucky country’ because despite the folly of politicians, and general fallibility of humans, we had wealth for toil.

Now we just give it away.


Hmmm. If we do simple extrapolation based on a battery density improvement rate of 5% a year, it takes about 30 years to get there. So it's not as crazy as it sounds - and it's also worth noting that there are incremental improvements in aerodynamics and materials so that gets you there faster...

However, as others have pointed out, the battery-powered plane doesn't get lighter as it burns fuel.


If we do simple extrapolation, a cellphone-sized battery will reach the 80kWh needed to power a car in as little as 180 years.

Expecting a 5% / year growth rate sustained for 30 years is very optimistic. It is far more likely that we'll hit some kind of diminishing return well before that.


More accurately, the calculation needs to factor in the fact that battery weight doesn’t decrease as charge is used.

Commercial aviation’s profitability hinges on being able to carry only as much fuel as strictly[1] required.

How can batteries compete with that constraint?

Also, commercial aviation aircraft aren’t time-restricted by refuelling requirements. How are batteries going to compete with that? Realistically, a busy airport would need something like a closely located gigawatt scale power plant with multi-gigawatt peaking capacity to recharge multiple 737 / A320 type aircraft simultaneously.

I don’t believe energy density parity with jet fuel is sufficient. My back of the neocortex estimate is that battery energy density would need to 10x jet fuel to be of much practical use in the case of narrow-body-and-up airliner usefulness.


You laid it out better than I. Thank you!


Thanks Walter!


An A320 can store 24k liters of fuel. Jet fuel stores 35 MJ/L. So, the plane carries 8.4E11 J of energy. If that was stored in a battery that had to be charged in an hour 0.23GW of electric power would be required.

So indeed, an airport serving dozens or hundreds of electric aircrafts a day will need obscene amounts of electric energy.


Jet engines are not 100% efficient.

Electric motors can be pretty close, 98% is realistic. Of course other parts of the system will lose energy, like conversion losses.

Of course that doesn't mean batteries are currently a viable replacement. One should still take efficiency into account in quick back of the envelope calculations.


Halve it to 0.11G then.

It makes no difference, we’d still need gigawatt scale electricity production, with some multiple of that at peak, just for a fairly unremarkable airport.


> It's coming from Toyota because Toyota can't wrap its head around not making engines.

Which is also the reason why its plug-in hybrids are so reliable, despite being dramatically more complex than either an EV or an ICE.

Toyota is very good at making engines, and it would be insane to throw away all that expertise to deliver a half-assed new product.


The energy density doesn't work for now. Everybody hoping for that breakthrough, and battery aircraft are moving into certain sectors (drone delivery, air taxis etc).


One of the trade offs is that engines are actually ridiculously heavy. Compact, extreme high power electric motors are starting to be commercialised. But also, fuel burns so you lose weight as you’re flying whereas batteries stay the same.

Electric aviation is interesting but as someone who knows a bit about the industry, biofuels make more sense here.


Structural batteries were supposed to be the solution where the density wasn't so important. I don't really have a good understanding of the ration of fuel weight to structural weight in existing aircraft though.


casing is around 25% of the mass of a cylindrical cell, with the rest being actual battery bits that can't have any stresses applied. is 25% weight saving that significant?


The idea is that you build the aircraft frame out of the battery.

If you can get it to work (a big if) you get to subtract the weight of the old frame before you make calculate the pseudo-density,


I understand, but that's my point. Currently the case is 25% of the battery. Only the case can be removed. If you move the fragile guts of the battery into the frame (in no way reducing their mass or the frame's), you're effectively turning that 25% case to 0%. So, the most you can save is 25% battery weight.

That doesn't really nudge the power density needle all that much, especially when you consider that you don't throw batteries out the back as their energy is depleted, as you do with fuels.


Jet engine and wing efficiency have increased enormously over the last 50 years.


With diminishing results.

Turbofans and supercritical airfoils are done to the point of engine manufacturers looking to propfans and alternative materials (carbon fibre) to eke out further efficiencies.

Although carbon fibre has significant down sides.


I have patented the idea of replacing the nitrogen in the cabin air with helium. I'm waiting for the money to roll in!


Looks like I picked the wrong week to quit sniffing glue.


It might also be because the Japanese government works very hard to have full employment and EVs require less labor.


What does this mean? They have electric vehicles too.


They are just too much in bed with big oil to want to switch, instead they spend rnd on hydrogen in order to mess up with renewables on purpose.


Hydrogen only makes electric vehicles look good and the only alternative. In fact, if this purposeful which I doubt, it probably helped stopped other companies from making hydrogen


The Mirai is a fuel cell EV. There is no engine. Not sure what your point is regarding engines?




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