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The Hydrogen Truck Problem Isn't the Truck

mikeayles.com

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Re: The Hydrogen Truck Problem Isn't the Truck

#41

Post by _carbyau_ »

dirk94018 wrote: post #8

Hydrogen has been the future as long as I have been paying attention to electric cars. There are many problems with it, including Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, and has terrible energy density by volume. You either compress it to 700 bar (heavy tanks), liquefy it at -253°C (energy-intensive), or store it in metal hydrides (heavy, slow release). Solid state batteries are…

> enable 10-minute charging.

I have a problem with the current physics of this. A car requires a LOT of energy to run. The electrical requirements "at the pump" are going to be pretty hefty for 10 minute charging.

Unless:

1. Reduce capacity requirements. IE Cars evolve smaller and smaller until they are practically aerodynamically efficient go-karts. A trend opposite of current affairs....

2. Charge for longer timeframes but swap in less than 10 minutes. IE standardise and replace batteries as needed.

I suspect that the "10 minute recharge" meme will be obviated by ridiculous ranges allowing us to then charge while sleeping instead.

Re: The Hydrogen Truck Problem Isn't the Truck

#42

Post by AnthonyMouse »

jMyles wrote: post #36
AnthonyMouse wrote: post #35

Earlier quoted context omitted.

Isn't that good for aviation? Makes it relatively less expensive to carry reserve energy you don't expect to use, don't have to pay the weight cost during takeoff when weight costs the most energy because you just charged the battery and once you're at cruising speed more weight is just neutral momentum. Probably the least convenient thing would be if you had to land and take off again somewhere without recharging.

> Probably the least convenient thing would be if you had to land and take off again somewhere without recharging. ...or... go around?

Except you started with 1500 miles of charge for a 200 mile flight because "fully charged" weighs less.

If you're up there waiting for a long time you don't have to fly in a tight circle at a high speed.

Re: The Hydrogen Truck Problem Isn't the Truck

#43

Post by defrost »

tim-tday wrote: post #40

Is it that hydrogen is a dirty fossil fuel in garish green makeup?

No, that's not the problem given in the article.

And no, that's not an accurate hot take ankle deep summary of the hydrogen industries arc.

* https://www.mckinsey.com/industries/oil-and-gas/our-insights...

Re: The Hydrogen Truck Problem Isn't the Truck

#44

Post by vardump »

_carbyau_ wrote: post #41
dirk94018 wrote: post #8

Hydrogen has been the future as long as I have been paying attention to electric cars. There are many problems with it, including Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, and has terrible energy density by volume. You either compress it to 700 bar (heavy tanks), liquefy it at -253°C (energy-intensive), or store it in metal hydrides (heavy, slow release). Solid state batteries are…

> enable 10-minute charging. I have a problem with the current physics of this. A car requires a LOT of energy to run. The electrical requirements "at the pump" are going to be pretty hefty for 10 minute charging. Unless: 1. Reduce capacity requirements. IE Cars evolve smaller and smaller until they are practically aerodynamically efficient go-karts. A trend opposite of current affairs.... 2. Charge for longer timefr…

Very much simplified, a 10 minute charge would mean 6C charging throughout the curve. 100 kWh battery would thus require 600 kW on average. Right now the most powerful MCS chargers deliver 1440 kW.

So not impossible, as long as the battery can handle the current. It's obvious that charging technology is not going to be the bottleneck.

(A real battery would probably have a charging curve that slows down towards the end, so more than 6C would be required in realistic conditions.)

Re: The Hydrogen Truck Problem Isn't the Truck

#45

Post by timmmmmmay »

Hydrogen is so hard to handle that NASA never really figured it out; hydrogen leaks just delayed Artemis 2 last week. There's been about 70 years of trying to solve these issues for space launch and very little progress. It doesn't seem like it'll be easier trying to do this as the scale of every gas station?

Re: The Hydrogen Truck Problem Isn't the Truck

#46

Post by xbmcuser »

_carbyau_ wrote: post #41
dirk94018 wrote: post #8

Hydrogen has been the future as long as I have been paying attention to electric cars. There are many problems with it, including Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, and has terrible energy density by volume. You either compress it to 700 bar (heavy tanks), liquefy it at -253°C (energy-intensive), or store it in metal hydrides (heavy, slow release). Solid state batteries are…

> enable 10-minute charging. I have a problem with the current physics of this. A car requires a LOT of energy to run. The electrical requirements "at the pump" are going to be pretty hefty for 10 minute charging. Unless: 1. Reduce capacity requirements. IE Cars evolve smaller and smaller until they are practically aerodynamically efficient go-karts. A trend opposite of current affairs.... 2. Charge for longer timefr…

2-3 min battery replacement is already a thing in China for trucks. The largest manufacture CATL is also pushing for safety and compatibility standards so all trucks can use all truck batteries in future. And for charging they are building charging stations with batteries that are charged slowly but can charge cars fast. The electricity revolution is just picking up pace

Re: The Hydrogen Truck Problem Isn't the Truck

#47

Post by ryantgtg »

schainks wrote: post #37
akamaka wrote: post #11

This is a very poor analysis, since it doesn’t account for the capital costs. Even if hydrogen is inefficient compared to batteries, it could win if the upfront investment was low enough to offset the additional fuel cost. This is quite obvious, since that’s why diesel trucks are winning today — the upfront cost of a diesel engine is cheap enough that it offsets the higher lifetime fuel costs. I do think that batteri…

Show me how the capital costs of rolling out high PSI hydrogen infra will be cheaper than building a power grid. You can even refit and re-use existing natural gas pipelines to move hydrogen if you want to cheat. I am willing to bet the costs per kW will still be crazy, especially at last mile where you are in an area populated by humans. I don't see a bright future for hydrogen in transport while we keep putting che…

Yeah. Vehicle costs are pretty much the same (for battery electric and fuel cell electric buses, at least) and are about 2-3x more than ICE. On-site hydrogen infra for fueling/storage is substantially more than charging equipment. H2 fuel is currently $10-20 per kg (the higher end accounts for vapor losses), which is, again, much greater than either diesel or electricity.

Re: The Hydrogen Truck Problem Isn't the Truck

#48

Post by trhway »

timmmmmmay wrote: post #45

Hydrogen is so hard to handle that NASA never really figured it out; hydrogen leaks just delayed Artemis 2 last week. There's been about 70 years of trying to solve these issues for space launch and very little progress. It doesn't seem like it'll be easier trying to do this as the scale of every gas station?

The article skips that i think most realistic and plausible option - fuel cell using hydrogen extracted from the standard hydrocarbon fuel right on the truck. Thus hydrogen would be present only in the short path - from fuel splitter to the fuel call. The fuel cell has higher efficiency than ICE and having electrical engine works better for trucks than ICE too. Such setup is overkill, at least for near future, for regular cars, while for trucks it seems worth the investment.

Re: The Hydrogen Truck Problem Isn't the Truck

#49

Post by svnt »

dirk94018 wrote: post #8

Hydrogen has been the future as long as I have been paying attention to electric cars. There are many problems with it, including Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, and has terrible energy density by volume. You either compress it to 700 bar (heavy tanks), liquefy it at -253°C (energy-intensive), or store it in metal hydrides (heavy, slow release). Solid state batteries are…

My favorite part is that high pressure hydrogen leaks can auto-ignite in air.

http://www.icders.org/ICDERS2007/abstracts/ICDERS2007-0255.p...

Re: The Hydrogen Truck Problem Isn't the Truck

#50

Post by mikestorrent »

_carbyau_ wrote: post #41
dirk94018 wrote: post #8

Hydrogen has been the future as long as I have been paying attention to electric cars. There are many problems with it, including Hydrogen is the smallest molecule. It leaks through seals, embrittles metals, and has terrible energy density by volume. You either compress it to 700 bar (heavy tanks), liquefy it at -253°C (energy-intensive), or store it in metal hydrides (heavy, slow release). Solid state batteries are…

> enable 10-minute charging. I have a problem with the current physics of this. A car requires a LOT of energy to run. The electrical requirements "at the pump" are going to be pretty hefty for 10 minute charging. Unless: 1. Reduce capacity requirements. IE Cars evolve smaller and smaller until they are practically aerodynamically efficient go-karts. A trend opposite of current affairs.... 2. Charge for longer timefr…

I like the idea of swappable batteries in theory, but in reality... well... that's a lot of logistics and a lot of potential for things to go wrong. Consider the swappable propane tank market, for instance; it's clear that returning cans need refurbishment and testing before you can give them back out to people. This implies it probably can't be just done on-site at a gas station.

They also weigh an absolute ton, so specialized lift equipment is needed; they take up space and will be very difficult to move around. So, are we expecting to stock a huge pile of batteries somewhere with an automatic loader/unloader that can handle multiple people at once with a quick turnover rate that can put away a 2000 pound battery? It's just too much infra, compared to a charging station...

And then there's the matter of the vehicle design; chassis rigidity is important and batteries, being a huge weight, need to be positioned properly with enough load bearing structure around them to support this. I'm imagining a hydraulic lift raising a 2000 pound battery up into my car; some massive brace needs to be attached below it to hold it up. Talk about difficult to get right; we've got harsh conditions like road salt and rust to deal with, and we have to make a fully automatable fastening device that can work at a random gas station with any brand of car... yikes.

You're actually much closer to the idea with the reduce-capacity idea. I had a Ford Focus Electric a while ago that had about 80km of range on a good day. This was more than enough for 90% of my driving; my old SUV handled the rest. Net carbon savings were huge; pity it was totaled in an accident or I'd have kept it going. Even at almost 10 years old it still kept a charge no problem and was a delight to drive compared to a normal Focus. My current EV has far more range but feels heavy and ponderous despite nearly 500 HP.

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