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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

#131

Post by mrspuratic »

NooneAtAll3 wrote: post #94
amsha wrote: post #59

There is a very to-the-point diagram called the Hydrogen Ladder [0] that classifies the usefulness of hydrogen by domain. The author makes a good case that, despite its versatility, hydrogen is almost always worse than some other clean technology for any use case. It’s hard to make, store, and use in a scalable/cheap way, and even generous estimates of future progress show a cost curve that requires subsidies basical…

did the picture die or smth? edit: no, even internet archive from a year ago shows no picture

"V5" article doesn't render (multiple browsers), try the older v4.1 version linked from it at the bottom (the faux "energy efficiency" graph).

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

#132

Post by m4rtink »

cenamus wrote: post #90
m4rtink wrote: post #2

I'm not really sure there is any place for a discussion - you would need a whole new infrastructure for hydrogen powered buses, while keeping a lot of the downsides of fossil fueled air breathing vehicles (eq. air filters filters regardless of if you burn the hydrogen or use it in fuel cells). With battery buses - you might need to slightly beef up the local transformer and installs some new wires and that's it. Or e…

Are those new in Brno? Can't remember them from the last time I was there, but sure sounds interesting

That started showing up maybe ~5 years ago ?

Googling a bit I found this article about the first series produced parcial trolley busses (eq. battery equiped) being delivered in 2018: https://www.bmhd.cz/aktuality/aktualita.php?1481

Since then it certainly expanded a lot & there are now regular lines that have the trolleybus go part of the line under its own power, like the recently introduced line to Soběšice: https://brnensky.denik.cz/zpravy_region/brno-mhd-prvni-linka...

Thanks to this you can go watch them stow/deploy their collectors at the Královo Pole nádraží stop at about any time during the day. :)

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

#133

Post by m4rtink »

martinald wrote: post #7
m4rtink wrote: post #2

I'm not really sure there is any place for a discussion - you would need a whole new infrastructure for hydrogen powered buses, while keeping a lot of the downsides of fossil fueled air breathing vehicles (eq. air filters filters regardless of if you burn the hydrogen or use it in fuel cells). With battery buses - you might need to slightly beef up the local transformer and installs some new wires and that's it. Or e…

While I agree with you; just to be clear it's not "slightly" beef up the local transformer. If you imagine a medium sized depot with 50 buses stabled at any one time, and 300kW chargers (I believe you could go higher), that's 15MW peak which is not trivial to add in many cities overnight. You really need some sort of HV connection for that kind of load, the existing local LV distribution grid isn't going to handle it…

Thats the genial thing about trolleybuses with batteries - there is alread a substantial city wide charging network, that is even distributed and enables on-the-go charging. :)

Sure, for regular battery buses without trolley collectors, indeed some new transformers might be needed. But even here, I wonder if you could make it somewhat distributed, with some charging happening at the line terminus where the drivers also often have to take a break anyway.

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

#134

Post by fluidcruft »

philjohn wrote: post #122
filmor wrote: post #109

Earlier quoted context omitted.

How is that efficiency calculated, respectively?

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…

BEVs aren't 100% efficient though so it's closer to 2x rather than 3x.

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

#135

Post by fluidcruft »

linedgolyi wrote: post #84
CraigJPerry wrote: post #81

Earlier quoted context omitted.

I thought they all had AVAS fitted? Are there markets where this isn’t the case?

Maybe? Problem is either that it can be and is always disabled by driver, or it's very quiet, because I as a healthy man in their 20s, hear the pavement tire noise before any other noise, and the car is already really close at that point

Most pedestrians have airpods in nowadays and probably couldn't hear an ambulance.

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

#136

Post by masklinn »

ReptileMan wrote: post #103
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.

EV has been tried with great success since the moment the electric motor was invented. Trams, metros, trolleybuses. The bottleneck for free range was always the battery - which was solved by the mobile phones. The electronics industry had the money to invest into batteries because of the premium that people were willing to pay for even minor battery improvements. And the economy of scale pushed it down to where a bat…

> The bottleneck for free range was always the battery - which was solved by the mobile phones.

I wouldn't say solved here. Significantly improved into usability yes, but there are still big issues with batteries:

- their low energy density means it's essentially impossible to have a long range in a small car, every long range EV is necessarily quite large, yet still has a shorter range than a city car

- specific energy remains meh, contributing to weight inflation (though by no means the only factor here)

- low temperature performance remains dreary and something you have to manage (and possibly hack / work around e.g. if your car only does automatic battery conditioning)

- while I think fast charge times are a bit overblown as a single driver on long trips (because stretching / resting every 2-3 hours is a good idea anyway), if you have relief drivers and can relay they're a significant impediment

Not that I think hydrogen has any future mind. But EVs do have a lot of drawbacks. And the amount of power you need available to charge a bus fleet in reasonable time is significant if you do pure battery.

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

#137

Post by masklinn »

rstuart4133 wrote: post #65
kalleboo wrote: post #62

Earlier quoted context omitted.

An example of such a line is in Sweden https://en.wikipedia.org/wiki/Iron_Ore_Line > From Riksgränsen on the national border to the Port of Narvik, the trains use only a fifth of the power they regenerate. The regenerated energy is sufficient to power the empty trains back up to the national border.

Similar thing happens in Australia: https://www.jalopnik.com/these-electric-trains-never-need-re... The twist: these trains aren't connected to the grid. They use regenerative braking to charge batteries when carting ore to the coast, and the batteries power the trip back to the mine.

IIRC there are mine trucks set up similarly in some locations, they're loaded at the top, regen downhill, and that's sufficient to power them back up the hill when empty.

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

#138

Post by foobarian »

hylaride wrote: post #116
nine_k wrote: post #54

Earlier quoted context omitted.

A diesel electric locomotive has no serious batteries, and no room for enough batteries to consume the energy of slowing down a train. At least it can dump it as heat without also producing fine dust, like mechanical brakes do.

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

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

#139

Post by petertodd »

praseodym wrote: post #111
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.

> 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.

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

#140

Post by dalyons »

misswaterfairy wrote: post #101
m4rtink wrote: post #2

I'm not really sure there is any place for a discussion - you would need a whole new infrastructure for hydrogen powered buses, while keeping a lot of the downsides of fossil fueled air breathing vehicles (eq. air filters filters regardless of if you burn the hydrogen or use it in fuel cells). With battery buses - you might need to slightly beef up the local transformer and installs some new wires and that's it. Or e…

> you would need a whole new infrastructure for hydrogen powered buses, while keeping a lot of the downsides of fossil fueled air breathing vehicles (eq. air filters filters regardless of if you burn the hydrogen or use it in fuel cells) Australia kind-of already had 'hydrogen' infrastructure and supply chains already, in LPG or 'autogas'. LPG (or dual petrol/LPG) used to be a popular option for small vehicle fuel in…

Battery and charging technology are getting better constantly. That low density niche won’t last long enough for hydrogen to compete, it’s going to be all EV soon enough.
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