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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

#61

Post by tjmc »

AnthonyMouse wrote: post #42
jMyles wrote: post #36

Earlier quoted context omitted.

> 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.

The issue is maximum take off weight. Presumably the discharged battery weight would be the one you use in the pre-flight MTOW calculations, because the worse case scenario is one where you're landing an almost discharged battery and have to go around.

Re: The Hydrogen Truck Problem Isn't the Truck

#62

Post by mikeayles »

_aavaa_ wrote: post #6

Good article, as always hydrogen for transport is dead. Unfortunately, as they say, what is dead can never die. And there will always be companies trying to siphon off public funds to do “trial runs”. One thing that seems wrong is in the efficiency comparison: step 1 for hydrogen should be grid transmission, not electrolyzer. Also, how come the BEV price doesn’t adjust in response to electricity prices (not that it w…

Good catches, both of them. The hydrogen pathway should include grid transmission before the electrolyser, you're right. In practice it doesn't change the overall ratio much (multiplying by 0.95 on both sides) but the diagram should be consistent.

The BEV cost not adjusting with the electricity slider is a bug, not a choice. I'll fix both. Thanks.

Re: The Hydrogen Truck Problem Isn't the Truck

#63

Post by mikeayles »

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…

Fair point that a full TCO comparison would be more complete, and it's something I'm planning to cover in a later post. But the capital cost argument actually reinforces the conclusion rather than undermining it. Hydrogen fuel cell trucks are currently 2-3x the price of diesel equivalents, roughly comparable to battery electric. The infrastructure CAPEX is dramatically higher for hydrogen (£2-5M per station vs. transformer upgrades for depot charging). And the fuel cost gap means hydrogen has higher opex too. Diesel wins today on upfront cost, yes, but hydrogen doesn't beat BEV on capital or operating costs in any current scenario I've seen. Happy to be shown numbers that say otherwise.

The big thing I haven't covered yet is HVO, which provides the WTT CO₂ saving at a slight fuel cost surcharge, which matters if a fleet is mandated to reduce their CO₂. The TCO assuming a £100k diesel truck and £200k lifetime fuel cost, a 10% HVO surcharge brings the TCO to £320k, versus a £250-350k BEV truck that costs maybe £80k in electricity over the same life. That's £320k with an 80-90% CO₂ reduction from a drop in fuel you can put in your existing trucks tomorrow, versus £280k for battery electric with zero tailpipe. Both of those are available now, with existing infrastructure. Hydrogen is asking you to spend £300k+ on the truck, £150k+ on fuel, and hope someone builds a station within range of your routes.

Re: The Hydrogen Truck Problem Isn't the Truck

#64

Post by mikeayles »

trhway wrote: post #48
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 re…

I have done a deep dive here: https://www.mikeayles.com/blog/on-vehicle-hydrogen-generatio...

Short answer, it takes more energy to generate than the energy it produces.

You can do things like only producing electrical power from the alternator when decelerating, ensuring no load comes off the engine, but that would require accumulation as you're not actually burning fuel then either.

But running the numbers on the power requirements, I reviewed one commercially available system (at 12v 14A) and calculated that the HHO they are able to produce is 0.037% by energy going into the engine vs regular fuel.

When presented with 0.037% of the fuel substituted, their 10-15% claim on fuel savings becomes a bit of a red flag.

Re: The Hydrogen Truck Problem Isn't the Truck

#65

Post by trhway »

mikeayles wrote: post #64
trhway wrote: post #48

Earlier quoted context omitted.

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 re…

I have done a deep dive here: https://www.mikeayles.com/blog/on-vehicle-hydrogen-generatio... Short answer, it takes more energy to generate than the energy it produces. You can do things like only producing electrical power from the alternator when decelerating, ensuring no load comes off the engine, but that would require accumulation as you're not actually burning fuel then either. But running the numbers on the p…

i meant hydrogen from regular fuel, not from water.

Re: The Hydrogen Truck Problem Isn't the Truck

#66

Post by shellfishgene »

RandallBrown wrote: post #56
mikestorrent wrote: post #50

Earlier quoted context omitted.

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…

Doesn't Nio have a few thousand battery swapping stations in China?

They just announced a while ago that they performed their 100 millionth battery swap, and just now "Nio's 3,750 battery swap stations delivered 2,073,500 battery swap services between February 10-23" (Chinese new year). Seems to work fine.

Re: The Hydrogen Truck Problem Isn't the Truck

#67

Post by cjbenedikt »

rfv6723 wrote: post #32
cjbenedikt wrote: post #2

Excellent analysis. Two points: what if 1) only surplus energy from offshore wind would be used for green H2 electrolysis and 2) the price would be at or below £/€/$ 1.50 per Kg?

The logistical nightmare of hydrogen makes its production price almost irrelevant. Using surplus wind energy for carbon capture to create synthetic fuels is much smarter because these liquids are compatible with our current global infrastructure. You bypass the need for expensive new pipelines and specialized tanks entirely. By binding green hydrogen into a stable synthetic hydrocarbon, you get a fuel that is easy to…

The price of H2 is a contributing factor to the price of synthetic fuels, though. Just saying. Otherwise I agree with your points on synthetic fuel.

Re: The Hydrogen Truck Problem Isn't the Truck

#68

Post by cjbenedikt »

mikeayles wrote: post #3
cjbenedikt wrote: post #2

Excellent analysis. Two points: what if 1) only surplus energy from offshore wind would be used for green H2 electrolysis and 2) the price would be at or below £/€/$ 1.50 per Kg?

Thanks. Both good questions, and they come up a lot. To be clear, I'm fully behind decarbonising freight. It's one of the hardest sectors to clean up and it needs serious attention. But hydrogen for road transport requires jumping in with both feet (due to infrastructure requirements) when there are dozens of smaller, commercially proven steps that get you equivalent results. Better route planning, driver training, a…

"...steel, ammonia, seasonal storage, maritime." Spot on, completely agree.

Re: The Hydrogen Truck Problem Isn't the Truck

#69

Post by jMyles »

tjmc wrote: post #61
AnthonyMouse wrote: post #42

Earlier quoted context omitted.

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.

The issue is maximum take off weight. Presumably the discharged battery weight would be the one you use in the pre-flight MTOW calculations, because the worse case scenario is one where you're landing an almost discharged battery and have to go around.

Yes, this was exactly my thought; maybe I needed to state it more clearly.

Re: The Hydrogen Truck Problem Isn't the Truck

#70

Post by akamaka »

mikeayles wrote: post #63
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…

Fair point that a full TCO comparison would be more complete, and it's something I'm planning to cover in a later post. But the capital cost argument actually reinforces the conclusion rather than undermining it. Hydrogen fuel cell trucks are currently 2-3x the price of diesel equivalents, roughly comparable to battery electric. The infrastructure CAPEX is dramatically higher for hydrogen (£2-5M per station vs. trans…

It would be a stronger argument if you first tried looking at the cases where hydrogen has an advantage. The port example you brought up, where hydrogen is produced on site, is a good one to analyze. If you can look at cost projections of fuels cells and electrolyzers vs. batteries over the next 20 years and demonstrate that there’s no chance hydrogen will catch up, that would be a very strong argument, since it doesn’t rely on the hand-wavy “fueling infrastructure will never happen” argument.
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