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Hydrogen vs. Battery Buses: A European Transit Reality Check

cleantechnica.com

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Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#161

Post by hylaride »

foobarian wrote: post #138
hylaride wrote: post #116

Earlier quoted context omitted.

They can (and do) have room if they're designed from the ground up for it. The engines for diesel electric trains are so large because they need to be sized to drive power for peak energy (usually accelerating and hills). If the energy can be stored, the engines for hybrid locomotives themselves can (and are) smaller. So far you're only seeing hybrid locomotives for trains that stop/start a lot (shunting trains and p…

I would imagine long range freight would be more likely to have long stretches of uphill grade which would mess with the minimum battery size

Yeah, that could be a problem. Even modern trains often now have multiple locomotives (including in the middle of train sets) to deal with range/weight, so who knows. There’s no reason hybrid trains can’t have multiple locomotives or battery bank-cars for those situations.

As I mentioned above, the freight lines are very conservative with new tech and amortize equipment over decades (often to the point where many rail cars are unsafe, especially outdated tank cars), so even if it exists we won’t see it in practice for awhile yet.

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#162

Post by praseodym »

petertodd wrote: post #139
praseodym wrote: post #111

Earlier quoted context omitted.

> Yes, you can refill quicker Unless the hydrogen fueling nozzle freezes to the car, which is apparently quite common in high humidity weather and/or when multiple cars are fueled consecutively. See e.g. https://www.sciencedirect.com/science/article/pii/S036031992...

That's just a minor problem, not a fatal flaw. Obviously you can fix that with a small heater for negligible energy cost.

Commercially available solutions seem to use a flow of nitrogen to purge condensation from the nozzle, which is quite a bit more complicated: https://www.weh.com/en_us/general-news/preventing-the-fuelin...

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#163

Post by stevesimmons »

spacebanana7 wrote: post #61
mmooss wrote: post #56

Earlier quoted context omitted.

> The biggest hydrogen bus fleet seems to be 35 vehicles From the OP: Cologne is one of the few relatively good news stories for hydrogen bus fleets. Regionalverkehr Köln (RVK) has become the largest operator of hydrogen fuel cell buses in Europe, with a fleet that reached 101 vehicles by late 2024 and is expected to grow to 160 by the end of 2025.

Still, their point was directionally correct. London has 1397 electric buses and Moscow has over 2300. https://en.m.wikipedia.org/wiki/Low_emission_buses_in_London https://en.m.wikipedia.org/wiki/Electric_buses_in_Moscow

And Minsk in Belarus has more than 1000 electric buses, of which 150 to 180 are powered by supercapacitors rather than batteries!

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#164

Post by ch_sm »

marcosdumay wrote: post #155
philjohn wrote: post #122

Earlier quoted context omitted.

https://www.sciencedirect.com/topics/engineering/fuel-cell-e... I believe all Hydrogen vehicles are using proton exchange membranes still, which have roughly 40-50% efficiency. And that's before you take into account that even the most cutting edge hydrogen refining processes are around 70% efficient. So 1kWh of energy input (electricity) will net you 3X the motive power when used directly in a BEV than first being c…

I don't think any hydrogen vehicle in actual use has a fuel cell (and if there's any, it's an incredibly rare exception). They are all internal combustion engines. Proton exchange membranes are very unreliable and expensive. They are also not power-dense, one that powers a bus will be very large.

It‘s actually the opposite: some hydrogen cars that use combustion exist, but they are really, really rare. Almost all hydrogen cars that are road legal use a fuel cell in combination with BEV parts to smooth out/extend power delivery.

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#165

Post by mmooss »

philjohn wrote: post #92
mmooss wrote: post #85

Earlier quoted context omitted.

If people followed that reasoning, there would be few EVs now because EVs had been tried for decades without success; so were airplanes and AI. If people quit as easily as you say hydrogen car manufacturers should, we wouldn't have much of anything.

Yes - but Hydrogen vehicles have not proven to match or even beat EV's in a lot of key metrics that matter. The biggest one is efficiency. 40% efficient is one figure I saw, versus 80% for EV's. Yes, you can refill quicker, but time to "refuel" EV's is dropping precipitously as well, and it's just all around safer than tanking around highly combustible liquid gas.

> Hydrogen vehicles have not proven to match or even beat EV's in a lot of key metrics that matter

Not yet. That is the nature of technological R&D - if we had the answers, we wouldn't be doing R&D.

AI before the last decade or so didn't beat other computer technologies in key metrics; should they have stopped developing it? Fusion power doesn't beat fission and other options in key metrics; solar didn't beat other sources in key metrics, including costs, ... - should humanity have stopped developing those things?

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#166

Post by mmooss »

marcosdumay wrote: post #156
mmooss wrote: post #82

Earlier quoted context omitted.

Nobody doubts EVs are more popular now. You should see the numbers for ICE buses too. The discussion is about the future.

Do you expect any problem to appear for batteries at the next century or so? What king of change do you expect on the future for it to not repeat the lessons we learned at the present? Fossil fuels are on the way out because we do expect problems. Do you have something similar for EVs?

Efficiency is always a problem. EVs wouldn't exist if they weren't more efficient than ICE vehicles, but there is still a cost to EVs - power generation, manufacturing, waste .... A new technology could increase efficiency.

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#167

Post by adrian_b »

bluGill wrote: post #151
preisschild wrote: post #145

Earlier quoted context omitted.

> Batteries work out better anyway though because they allow you to go around obsticals (roadwork, cars illegally parked in the land...) The pantographs of trolleybuses are often pretty long, so they can switch to the other lane to avoid obstacles.

Which does no good if the whole road is blocked.

Which is why many European cities have lanes reserved for public transportation, in order to prevent stupid car drivers to block the traffic.

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#168

Post by adrian_b »

coderenegade wrote: post #110
chermi wrote: post #11

The hydrogen economy hasn't made since to me from when I first heard about it 15+years ago. It's one of the clearest examples of academics not understanding how business works.

Hydrogen makes sense as a chemical feedstock for methanol and ammonia. It also scales well to grid energy storage, because you can add hundreds of GWhs at a time, and the technology is mature (Moss Bluff opened in 1983). You wouldn't use hydrogen in vehicles, because methanol is easy to make, and is a much better fuel for non-aero applications. Shipping is moving to methanol for that reason.

Hydrogen also makes sense as a reducing agent replacing coal for producing steel and other metals, where it makes possible the production of metals with less impurities.

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#169

Post by pipodeclown »

nautilius wrote: post #113
philjohn wrote: post #92

Earlier quoted context omitted.

Yes - but Hydrogen vehicles have not proven to match or even beat EV's in a lot of key metrics that matter. The biggest one is efficiency. 40% efficient is one figure I saw, versus 80% for EV's. Yes, you can refill quicker, but time to "refuel" EV's is dropping precipitously as well, and it's just all around safer than tanking around highly combustible liquid gas.

Efficiency is the standard red herring of the battery crowd - if efficiency was the prime motivation, we would all be driving bicycles and SUV or sportscars would not exist. What are your other metrics? It’s an electric drivetrain with all advantages, but with the range of a gasoline car. Refueling cNG or LNG is standard in Europe, LH2 works just fine. Google “burning Tesla” for that ridiculous take on why batteries…

Efficiency doesn't matter when you're literally pumping energetic liquid from the ground. It does matter when you need to build 150% more solar panels to produce the energy to create your energetic liquid/gas.

Re: Hydrogen vs. Battery Buses: A European Transit Reality Check

#170

Post by pipodeclown »

marcosdumay wrote: post #155
philjohn wrote: post #122

Earlier quoted context omitted.

https://www.sciencedirect.com/topics/engineering/fuel-cell-e... I believe all Hydrogen vehicles are using proton exchange membranes still, which have roughly 40-50% efficiency. And that's before you take into account that even the most cutting edge hydrogen refining processes are around 70% efficient. So 1kWh of energy input (electricity) will net you 3X the motive power when used directly in a BEV than first being c…

I don't think any hydrogen vehicle in actual use has a fuel cell (and if there's any, it's an incredibly rare exception). They are all internal combustion engines. Proton exchange membranes are very unreliable and expensive. They are also not power-dense, one that powers a bus will be very large.

That is completely incorrect, it is the opposite.
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