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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 downs

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 even better, do what the city mass transit company does here in Brno, Czech Republic - get trolley busses with batteries, that charge from the overhead wires while on the way, so they can then continue to serve additional destinations past the terminus of road electrification. It is also super handy for any road work, they just automatically stow their collectors and then once again under wires, deploy them. There is usually a small trough around the wires at this spot, guiding the 2 collectors to the 2 wires. As a result, the driver does not have to leave the vehicles when connecting or disconnecting from wired power. And it looks super cool! :)

martinald 2y ago
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. I do definitely think green hydrogen has a big future ahead of itself though. We still use an absolutely ridiculous about of H2 in industrial processes (especially fertilizers). Europe could produce huge amounts of fertilizers in the summer in the future with all the excess solar and wind it has via this method. It seems to me hydrogen skipped a step - focus on replacing hydrogen feedstocks in industrial processes directly with green hydrogen, instead of replacing stuff up the chain that can be done with batteries directly anyway.
- londons_explore 2y ago
  Any decent sized installation will use current clamps at the local transformers to scale the charging rate up and down depending on other users in the local area. Ie. in the evening whilst everyone has their ovens on, charging might only be 3 kW per bus, but then at 1am when everyone has gone to bed, it can be 30 kW per bus. Using that approach, you can get far more capacity out of old infrastructure. Unfortunately, some utility companies aren't amenable to that approach, and instead insist you pay to upgrade the infra, since to them it's a free upgrade.
  - martinald 2y ago
    Not really. Buses need to be charged whenever, not just overnight (it creates enormous logistical problems otherwise). A typical bus route running 5am to midnight say is not going to last with one charge, depending on length. Also, if it is a cold night and everyone leaves electric heating/heat pumps on, what happens then? Noone can get to work the next day? Regardless most urban transformers are not going to have 15MW of overnight capacity spare even on a good day. The largest LV substations might be 30MVA in the UK at least - they won't just have half capacity suddenly free.
    - adgjlsfhk1 2y ago
      Lots of busses are split shift. i.e. they drive from ~6:30am to ~9:30am and ~4pm to 7pm. This means that a significant portion of your bus fleet will be able to charge during the middle of the day when energy demand is relatively low and there's a ton of solar power. As an aside, we have so far really dropped the ball on level 1 electric vehicle chargers at offices. As solar power and EV numbers increase, it's pretty obvious that we want more cars charging during the day and fewer charging at night.
      - linedgolyi 2y ago
        >we have so far really dropped the ball on level 1 electric vehicle chargers at offices Our govt. really did a disservice to transition to EVs by slapping on a big tax to anyone even brushing against a charger at work: 120€/year
      - bmicraft 2y ago
        Where do you live that buses aren't running during most of the day? That just seems absurd to me. Buses in my city run at only slightly reduced (from the rush hour peak) intervals for the whole day
        martinald 2y ago
        Agreed, I assume this is a very US centric viewpoint. Wherever I have been in Europe the schedule is basically the same throughout the day, with reduced frequency in the evenings. Potentially slightly higher at rush hours, but nothing dramatic. Not sure why you are being downvoted.
- discardable_dan 2y ago
  Luckily, humans are rather expert water-boilers at this point in time.
- smeeger 2y ago
  a lot of people like to laugh very, very loudly at the idea of upgrading the grid to handle EVs. simply remind them that at one point in time there was no grid at all. the grid is not some magical entity that cant be changed
  - HPsquared 2y ago
    It's a bit like the difference between building a new house, vs renovating an old one. Different skills are required and the renovation project can actually be more complex than new build.
- m4rtink 2y ago
  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.
- crote 2y ago
  You wouldn't need 300kW chargers, though! Battery buses have a battery capacity of around 400kWh. Assuming they are stabled for 6 hours overnight, that's only a charging power of 66kW. Suddenly your depot needs a connection with a peak capacity of 3.3MW instead of the proposed 15MW. This can get significantly better in practice. There's a peak transit demand during commute hours, but that means there are quite a few unused buses in the middle of the day. Those can charge at the depot to take advantage of cheap daytime solar. A lot of bus routes are timed, with a waiting time of 5 to 10 minutes at the turnaround point. Place an overhead charger here, and the charging demand can be distributed across the day. As a bonus, this also reduced the battery capacity needed - and the associated lower weight reduces total energy demand as well. Sure, bus depots are going to need beefy connections, but that's hardly an insurmountable obstacle. The ongoing rapid rollout shows that it simply isn't a such a big issue in practice.
  - martinald 2y ago
    You're oversimplifying on many angles. Firstly you have charging losses - and you're assuming that you can charge at the same rate consistently over the cycle of the charge. Secondly, doing it like that massively reduces operational flexibility. If buses are all late back (bad traffic for example) you would want to charge more aggressively than the 60kW. You can't so you're going to have buses that are low on charge the next day. Finally, it's all a bit moot. In most areas you do not have 3MW of spare capacity on the LV network to suddenly plug into. You're going to need a new HV connection or dramatic LV grid reinforcement, so you might as well put a decent connection in at that point. The cost is basically the same, most of the cost is in permits and civils. Your idea to place charging points at turnaround points is also not as feasible as you make out. It's incredibly hard to do that (TfL massively struggles to get planning for a simple toilet block for drivers at turnaround points) and they are not designed in a way to have buses in a certain exact position to charge often. And even if you could if buses are late they cannot skip the turnaround like now as they need to charge. This will cause massive cascading delays down the route for the rest of the day. Grid connections are the reason rollout is so slow, at least in the UK. There is relatively plentiful funding for it but most depots are now completely maxed out in power availability - any spare capacity has already been used and the LV DNO queue is 10+ years for local reinforcement.
Kirby64 2y ago
> 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). Unless you burn the hydrogen, you aren't producing any emissions... unless you count water as an emission. Fuel cells don't produce any emissions. Burning hydrogen though, does produce some emissions, however it's pretty minimal. I believe it's only NOx, and even then at far lower rates compared to gas vehicles. No CO2, CO, or any other stuff from gas or not-fully-burnt gas. That said, I agree hydrogen has seemingly no place in something like buses. Frankly, the only places that I see hydrogen has any future is either going to be for planes and boats, or potentially for intermediate storage akin to batteries (i.e., create hydrogen with excess solar/wind power).
- vardump 2y ago
  Don't fuel cells require air without any contaminants, thus air filters? So you still need filters, this not for the exhaust, but for the intake.
  - Kirby64 2y ago
    Is that a real problem here? Air filters on ICE cars are easy and not that frequent. You need cabin air filters regardless for passengers, so changing those at the same time isn’t that much different. Filters are cheap unless fuel cell ones are super expensive for some reason.
    - vardump 2y ago
      The air purity requirements for fuel cells are rather demanding. Impurities will destroy them. ICE air filter would destroy them in no time.
      - Kirby64 2y ago
        Hm, I looked up how much a Toyota mirai filter is and they’re quite expensive. $270 it looks like from a 3rd party? It’s every 36k miles though. Not every year/12k like a normal air filters.
cenamus 2y ago
Are those new in Brno? Can't remember them from the last time I was there, but sure sounds interesting
- m4rtink 2y ago
  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 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-troleje-baterka-parcialni-trolejbus-sobesice-sadova-bystrc.html 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. :)
  - satiric 2y ago
    Do the poles fall off the wires a lot? Our trolley buses in Seattle have a bit of a problem with that. According to the folks I know in San Francisco, theirs do too. They're great otherwise though. Seattle's newer trolley buses can operate off the wire for about 3 miles/5 kilometers (on a LiFePO4 battery) which helps a bit.
    - m4rtink 2y ago
      I have seen it happen a few times, but it does not seem to happen very often. I don't think I ever saw it happen when riding a trolley bus - usually I saw a stopped trolleybus with the driver stepping out & reatacching the collector poles before driving away. Took a couple minutes at most. It was usually in some tricky spots - trolley wires crossing streetcar wire on Konečného náměstí (yeah, we have both :) ) or on the top of the rather steep slope of the Kotlářská street next to the Natural sciences faculty of the Masaryk university. I guess the new trolley busses with batteries and poles thatr can be stowed automatically might be even better for this - no need to fix the poles immediately, but wait for a regular stop or even the line terminus & just use the battery. Also once when touring one of the trolleybus depos (the small one in Husovice) the local maintenance chief mentioned that the one roundabout wired for trolley buses (yes, that exists) is a pain to maintain & maybe they could scrap it in the future, with the busses crossing it on batteries instead. :)
misswaterfairy 2y ago
> 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 Australia in the 2000s though has slowly declined due to petrol/electric hybrids coming along. https://www.abc.net.au/news/2023-04-19/lpg-cars-disappearing-from-roads-gas-renewable-fuel-vehicles/102236128 https://www.abc.net.au/news/2023-04-19/lpg-cars-disappearing... That said, it's possible to convert diesel engines to burn a 90% hydrogen/10% diesel mix, which could dramatically alter those numbers: https://www.unsw.edu.au/news/2024/08/converting-diesel-engines-to-run-on-hydrogen https://www.unsw.edu.au/news/2024/08/converting-diesel-engin... It shouldn't be too difficult to bring back 'autogas' infrastructure in Australia. And if we can, I don't see why others couldn't deploy it made sense to do so. Liquid/gas fuels make much more sense in very-low to moderate density areas with long distances between populated centres. Batteries make much more sense in high population density areas with relatively short trips. Whilst I agree it's not as ideal as a true zero-emissions thing, it's certainly a stepping stone to greatly accelerate the decarbonisation of our fuels, by allowing many to convert internal combustion engines to use much cleaner fuels, without having to buy brand new vehicles. Given that petrol and diesel these days are usually almost double the cost per litre of LPG in Australia, and that a lot of decently sized long range EVs are still very expensive in Australia, especially considering cost-of-living pressures and the distances many Aussies have to drive in rural and remote areas where EVs just aren't practical, I'm a little surprised LPG hasn't made a comeback. Australia has since kicked off a project to construct a large green hydrogen generation plant in Western Australia, due to be producing by 2029 and fully operational by the end of 2031, so hydrogen could become a pretty big deal in by 2030. https://research.csiro.au/hyresource/murchison-hydrogen-renewables-project/ https://research.csiro.au/hyresource/murchison-hydrogen-rene...
- perilunar 2y ago
  > many Aussies have to drive in rural and remote areas where EVs just aren't practical I’m currently in rural NW NSW, and it seems to me that BEVs would be ideal out here once they get a bit cheaper. Plenty of sunlight. Plenty of rooftop solar — every second house and farm shed has solar panels already. Powering farm vehicles from local solar instead of imported diesel seems logical and inevitable really.

martinald 2y ago

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. I do definitely think green hydrogen has a big future ahead of itself though. We still use an absolutely ridiculous about of H2 in industrial processes (especially fertilizers). Europe could produce huge amounts of fertilizers in the summer in the future with all the excess solar and wind it has via this method. It seems to me hydrogen skipped a step - focus on replacing hydrogen feedstocks in industrial processes directly with green hydrogen, instead of replacing stuff up the chain that can be done with batteries directly anyway.

londons_explore 2y ago
Any decent sized installation will use current clamps at the local transformers to scale the charging rate up and down depending on other users in the local area. Ie. in the evening whilst everyone has their ovens on, charging might only be 3 kW per bus, but then at 1am when everyone has gone to bed, it can be 30 kW per bus. Using that approach, you can get far more capacity out of old infrastructure. Unfortunately, some utility companies aren't amenable to that approach, and instead insist you pay to upgrade the infra, since to them it's a free upgrade.
- martinald 2y ago
  Not really. Buses need to be charged whenever, not just overnight (it creates enormous logistical problems otherwise). A typical bus route running 5am to midnight say is not going to last with one charge, depending on length. Also, if it is a cold night and everyone leaves electric heating/heat pumps on, what happens then? Noone can get to work the next day? Regardless most urban transformers are not going to have 15MW of overnight capacity spare even on a good day. The largest LV substations might be 30MVA in the UK at least - they won't just have half capacity suddenly free.
  - adgjlsfhk1 2y ago
    Lots of busses are split shift. i.e. they drive from ~6:30am to ~9:30am and ~4pm to 7pm. This means that a significant portion of your bus fleet will be able to charge during the middle of the day when energy demand is relatively low and there's a ton of solar power. As an aside, we have so far really dropped the ball on level 1 electric vehicle chargers at offices. As solar power and EV numbers increase, it's pretty obvious that we want more cars charging during the day and fewer charging at night.
    - linedgolyi 2y ago
      >we have so far really dropped the ball on level 1 electric vehicle chargers at offices Our govt. really did a disservice to transition to EVs by slapping on a big tax to anyone even brushing against a charger at work: 120€/year
    - bmicraft 2y ago
      Where do you live that buses aren't running during most of the day? That just seems absurd to me. Buses in my city run at only slightly reduced (from the rush hour peak) intervals for the whole day
      - martinald 2y ago
        Agreed, I assume this is a very US centric viewpoint. Wherever I have been in Europe the schedule is basically the same throughout the day, with reduced frequency in the evenings. Potentially slightly higher at rush hours, but nothing dramatic. Not sure why you are being downvoted.
discardable_dan 2y ago
Luckily, humans are rather expert water-boilers at this point in time.
smeeger 2y ago
a lot of people like to laugh very, very loudly at the idea of upgrading the grid to handle EVs. simply remind them that at one point in time there was no grid at all. the grid is not some magical entity that cant be changed
- HPsquared 2y ago
  It's a bit like the difference between building a new house, vs renovating an old one. Different skills are required and the renovation project can actually be more complex than new build.
m4rtink 2y ago
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.
crote 2y ago
You wouldn't need 300kW chargers, though! Battery buses have a battery capacity of around 400kWh. Assuming they are stabled for 6 hours overnight, that's only a charging power of 66kW. Suddenly your depot needs a connection with a peak capacity of 3.3MW instead of the proposed 15MW. This can get significantly better in practice. There's a peak transit demand during commute hours, but that means there are quite a few unused buses in the middle of the day. Those can charge at the depot to take advantage of cheap daytime solar. A lot of bus routes are timed, with a waiting time of 5 to 10 minutes at the turnaround point. Place an overhead charger here, and the charging demand can be distributed across the day. As a bonus, this also reduced the battery capacity needed - and the associated lower weight reduces total energy demand as well. Sure, bus depots are going to need beefy connections, but that's hardly an insurmountable obstacle. The ongoing rapid rollout shows that it simply isn't a such a big issue in practice.
- martinald 2y ago
  You're oversimplifying on many angles. Firstly you have charging losses - and you're assuming that you can charge at the same rate consistently over the cycle of the charge. Secondly, doing it like that massively reduces operational flexibility. If buses are all late back (bad traffic for example) you would want to charge more aggressively than the 60kW. You can't so you're going to have buses that are low on charge the next day. Finally, it's all a bit moot. In most areas you do not have 3MW of spare capacity on the LV network to suddenly plug into. You're going to need a new HV connection or dramatic LV grid reinforcement, so you might as well put a decent connection in at that point. The cost is basically the same, most of the cost is in permits and civils. Your idea to place charging points at turnaround points is also not as feasible as you make out. It's incredibly hard to do that (TfL massively struggles to get planning for a simple toilet block for drivers at turnaround points) and they are not designed in a way to have buses in a certain exact position to charge often. And even if you could if buses are late they cannot skip the turnaround like now as they need to charge. This will cause massive cascading delays down the route for the rest of the day. Grid connections are the reason rollout is so slow, at least in the UK. There is relatively plentiful funding for it but most depots are now completely maxed out in power availability - any spare capacity has already been used and the LV DNO queue is 10+ years for local reinforcement.

Kirby64 2y ago

> 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). Unless you burn the hydrogen, you aren't producing any emissions... unless you count water as an emission. Fuel cells don't produce any emissions. Burning hydrogen though, does produce some emissions, however it's pretty minimal. I believe it's only NOx, and even then at far lower rates compared to gas vehicles. No CO2, CO, or any other stuff from gas or not-fully-burnt gas. That said, I agree hydrogen has seemingly no place in something like buses. Frankly, the only places that I see hydrogen has any future is either going to be for planes and boats, or potentially for intermediate storage akin to batteries (i.e., create hydrogen with excess solar/wind power).

vardump 2y ago
Don't fuel cells require air without any contaminants, thus air filters? So you still need filters, this not for the exhaust, but for the intake.
- Kirby64 2y ago
  Is that a real problem here? Air filters on ICE cars are easy and not that frequent. You need cabin air filters regardless for passengers, so changing those at the same time isn’t that much different. Filters are cheap unless fuel cell ones are super expensive for some reason.
  - vardump 2y ago
    The air purity requirements for fuel cells are rather demanding. Impurities will destroy them. ICE air filter would destroy them in no time.
    - Kirby64 2y ago
      Hm, I looked up how much a Toyota mirai filter is and they’re quite expensive. $270 it looks like from a 3rd party? It’s every 36k miles though. Not every year/12k like a normal air filters.

cenamus 2y ago

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

m4rtink 2y ago
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 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-troleje-baterka-parcialni-trolejbus-sobesice-sadova-bystrc.html 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. :)
- satiric 2y ago
  Do the poles fall off the wires a lot? Our trolley buses in Seattle have a bit of a problem with that. According to the folks I know in San Francisco, theirs do too. They're great otherwise though. Seattle's newer trolley buses can operate off the wire for about 3 miles/5 kilometers (on a LiFePO4 battery) which helps a bit.
  - m4rtink 2y ago
    I have seen it happen a few times, but it does not seem to happen very often. I don't think I ever saw it happen when riding a trolley bus - usually I saw a stopped trolleybus with the driver stepping out & reatacching the collector poles before driving away. Took a couple minutes at most. It was usually in some tricky spots - trolley wires crossing streetcar wire on Konečného náměstí (yeah, we have both :) ) or on the top of the rather steep slope of the Kotlářská street next to the Natural sciences faculty of the Masaryk university. I guess the new trolley busses with batteries and poles thatr can be stowed automatically might be even better for this - no need to fix the poles immediately, but wait for a regular stop or even the line terminus & just use the battery. Also once when touring one of the trolleybus depos (the small one in Husovice) the local maintenance chief mentioned that the one roundabout wired for trolley buses (yes, that exists) is a pain to maintain & maybe they could scrap it in the future, with the busses crossing it on batteries instead. :)

misswaterfairy 2y ago

> 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 Australia in the 2000s though has slowly declined due to petrol/electric hybrids coming along. https://www.abc.net.au/news/2023-04-19/lpg-cars-disappearing-from-roads-gas-renewable-fuel-vehicles/102236128 https://www.abc.net.au/news/2023-04-19/lpg-cars-disappearing... That said, it's possible to convert diesel engines to burn a 90% hydrogen/10% diesel mix, which could dramatically alter those numbers: https://www.unsw.edu.au/news/2024/08/converting-diesel-engines-to-run-on-hydrogen https://www.unsw.edu.au/news/2024/08/converting-diesel-engin... It shouldn't be too difficult to bring back 'autogas' infrastructure in Australia. And if we can, I don't see why others couldn't deploy it made sense to do so. Liquid/gas fuels make much more sense in very-low to moderate density areas with long distances between populated centres. Batteries make much more sense in high population density areas with relatively short trips. Whilst I agree it's not as ideal as a true zero-emissions thing, it's certainly a stepping stone to greatly accelerate the decarbonisation of our fuels, by allowing many to convert internal combustion engines to use much cleaner fuels, without having to buy brand new vehicles. Given that petrol and diesel these days are usually almost double the cost per litre of LPG in Australia, and that a lot of decently sized long range EVs are still very expensive in Australia, especially considering cost-of-living pressures and the distances many Aussies have to drive in rural and remote areas where EVs just aren't practical, I'm a little surprised LPG hasn't made a comeback. Australia has since kicked off a project to construct a large green hydrogen generation plant in Western Australia, due to be producing by 2029 and fully operational by the end of 2031, so hydrogen could become a pretty big deal in by 2030. https://research.csiro.au/hyresource/murchison-hydrogen-renewables-project/ https://research.csiro.au/hyresource/murchison-hydrogen-rene...

perilunar 2y ago
> many Aussies have to drive in rural and remote areas where EVs just aren't practical I’m currently in rural NW NSW, and it seems to me that BEVs would be ideal out here once they get a bit cheaper. Plenty of sunlight. Plenty of rooftop solar — every second house and farm shed has solar panels already. Powering farm vehicles from local solar instead of imported diesel seems logical and inevitable really.