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I'm very skeptical whether it makes any sense to use hydrogen on a train. We know since many decades how to run trains on electricity. It's an established tech

by hannob 6y ago

I'm very skeptical whether it makes any sense to use hydrogen on a train. We know since many decades how to run trains on electricity. It's an established technology. It seems hydrogen trains are a cheap excuse for places where infrastructure is lacking and train tracks haven't been electrified. Except it's not cheap, because physics dictates using hydrogen will always be much less efficient compared to direct electricity use, as it includes an additional conversion step. I think developing hydrogen infrastructure is important for sectors where no other alternatives are available. For sectors were established technologies for electrifiation already exist - not so much.

gsnedders 6y ago
There's plenty of train lines in the world that see very few trains, maybe only one an hour, where the business case for electrification is much weaker. Many of these lines are already questionable from a business case point of view which can deter anything that would increase infrastructure costs, and if hydrogen trains can approach the operational cost of electric trains then there's a clear business case for them.
- hannob 6y ago
  > if hydrogen trains can approach the operational cost of electric trains That's exceptionally unlikely. You go from "use electricity to run a train" to "use electricity to run an electrolyseur, fill hydrogen into hydrogen tanks on the train, use hydrogen to power a fuel cell to generate electricity, use that electricity to run a train".
  - i_am_proteus 6y ago
    You need to add "build electric lines over entire length railway" to the left side of the equation and "build a hydrogen locomotive" to the right side.
  - nine_k 6y ago
    Hydrogen is easier to store than electricity, and you can produce it at times where electricity price is zero or negative (very sunny days at photovoltaic plants, very windy days at wind turbine plants, 3am at nuclear plants). Processes more efficient than electrolysis do exist. I suppose safe storage and transportation of hydrogen is a major cost, though. Hydrogen gets absorbed into metals, because their crystalline lattices act like sponges for molecules this small. Worse yet, hydrogen can seep through things that work as impenetrable solids for other gases. And hydrogen flame is all but invisible (most radiation is infrared, nearly no visible light).
- owenversteeg 6y ago
  Yep. The trains in the article (Cuxhaven-Bremerhaven) go once per hour. That entire region of Germany, and the area of the Netherlands that borders it, has an enormous amount of trains running on a 1x/hourly schedule. Groningen-Leeuwarden, Groningen-Delfzijl etc etc. All running (diesel-electric) Stadler FLIRT trains, which have taken the world by storm. The political decisions in these less populated regions are similar to small town politics in two ways: the budgets are tiny (aka no money for electrification) and a fairly small group can push things through if it fits their agenda. For those reasons I think these hydrogen trains could totally become popular for less densely populated areas like this.
  - tinus_hn 6y ago
    Just like just about every line in the Netherlands, there’s a train from Groningen to Leeuwarden and Delfzijl every 30 minutes.
pjc50 6y ago
The fixed cost and time consumption of electrification is quite high. I'm not sure about hydrogen specifically, but just as steam trains had a coal+water "tender" behind the engine, it seems not unreasonable to have a "battery" car on a train. Whether that's a tank of H2 or just a boxcar full of 18650 cells (anyone care to do the maths on that?)
- Gibbon1 6y ago
  I tried doing the math a few years ago. I did another search and up popped this. http://www.brooklynrail.net/science_of_railway_locomotion.html http://www.brooklynrail.net/science_of_railway_locomotion.ht... Which has the comment: At the same speed, same load (GCW) and on level ground, any steel wheeled railway vehicle is 24.6 times more energy efficient than any large rubber tire road vehicle, regardless of the type of power source. My hand wavy argument would be, to go 300 miles a passenger car needs 33% (guess) of it's weight to be batteries. But a truck is probably 2-2.5 times more efficient. So would only need 33% / 2.25 (split the middle between 2 and 2.5) or 15%. If a 4000 ton train is 25 times more effecient than a truck as started above then. 15%/25 is 0.6%. So the battery for a 4000 ton train would weigh 4000 * 0.6% -> 24 tons. Seems to pencil out to me.
  - gsnedders 6y ago
    Note that the majority of hydrogen trains currently under development are all multiple units, and don't have dedicated locomotives. In the UK at least, track access charges push things towards distributed traction in part because of the axle loadings of any dedicated locomotive (or battery car). You see this to varying degrees across countries where speed is relevant. To take as an example: each British Class 802 motor car has a 1550 litre fuel tank. If we (slightly optimistically) assume the diesel engine is 50% efficient, and diesel fuel to have 10.8kWh/L energy density, then that's 8370kWh of energy produced. The Tesla 3 battery pack manages 160Wh/kg, so to carry 8370kWh the battery pack would be 52 tonnes. That's more than each car currently weighs in total. And a nine-car train has five such fuel tanks and engines.
    - 6y ago
globular-toast 6y ago
Overhead lines are an eyesore and third rails are dangerous. I wouldn't consider electrification the be all and all for railways. It comes with tradeoffs like anything else.
- ben_w 6y ago
  I’ve never understood the aesthetic argument given the railways themselves — and indeed major roads — are something I find extremely ugly.
  - chrisseaton 6y ago
    You never understood why people think they’re ugly given that you think they’re ugly as well? What?
    - ben_w 6y ago
      I’ve never understood why electrification makes it worse when it’s ugly without, and when the alternatives are also ugly.
      - chrisseaton 6y ago
        The point is electrification via gantries makes it much more ugly. A railway line disappears into the ground somewhat, and to some people is actually attractive, even with emissions from a combustion engine. https://en.wikipedia.org/wiki/Glenfinnan_Viaduct https://en.wikipedia.org/wiki/Glenfinnan_Viaduct Electric gantries are seen to many people are far more intrusive to the landscape, and even destructive to landmarks, since they stick up into the air.
        gsnedders 6y ago
        By way of comparison, the Royal Border Bridge, with relatively lightweight and specifically designed gantries: https://upload.wikimedia.org/wikipedia/commons/9/93/60163_Tornado_7_March_2009_Berwick.jpg https://upload.wikimedia.org/wikipedia/commons/9/93/60163_To...
tremon 6y ago
Passenger service is usually high-usage enough that the cost of electrification is worthwhile. But many freight-only lines still use diesel, even in areas where a majority of the rail net has been electrified, because little-used supply tracks lack an incentive to electrify them. If we can replace those diesel lines with hydrogen, that's a win. Also note that the motors themselves are electric, so when this train is running on an electrified section, it could still use the overhead lines. Not sure if modern diesel engines offer that same option (i.e. if the diesel is purely used as a generator for an otherwise electric engine).
- tobylane 6y ago
  Yes, all the diesel train engines are diesel-electric, and on some routes they use bi-mode (eg electric London to near Bristol, diesel-electric to Cardiff) trains.
MLR 6y ago
Something like 60% of the UK rail network is unelectrified and recent electrification projects have been ruinously expensive, we need something to fill in the gaps and hydrogen definitely has potential.
- gsnedders 6y ago
  > Something like 60% of the UK rail network is unelectrified and recent electrification projects have been ruinously expensive, we need something to fill in the gaps and hydrogen definitely has potential. It's not as bad as is often made out; with relatively few exceptions (GWML most prominently) most recent electrification programmes in the UK haven't been too much above European norms. In general, the reasons why costs have been higher in the UK are: * other countries having fairly constant ongoing electrification work leading to availability of skilled staff (versus massively spikes of electrification, then nothing for a decade or more), * many more structures (e.g., overbridges, tunnels) close to the limits of the loading gauge and hence more structures work needed * track access being more difficult in the UK (in general prolonged closures are harder to get approval for), and * operators being compensated for service disruption. At this point the UK really just needs an ongoing programme of electrification, as we now have high-quality modern off-the-shelf parts for most needs approved and in use on new projects, and we have designs that meet the requirements of almost all current routes. Also worth bearing in mind is the recently announced Scottish Government plan to decarbonise rail in Scotland by 2030, which includes electrifying all the major lines in Scotland. (A few won't be, and hydrogen trains have been mooted for them, but these are mostly lines with a few trains per day where the business case for electrification is always going to be weakest, especially combined with them often being in the most challenging terrain.)
- fyfy18 6y ago
  Have there been any experiements (on a long distance route) to have battery packs on trains that are fast-charged at stations? In the UK a lot of routes are at least partially electrified, and EV chargers have proved it is fairly easy to supply a few hundred kilowatt electric supply to urban areas. I know there are trams that work like this, but I'm wondering if the tech could be scaled up to trains. https://en.m.wikipedia.org/wiki/Acumulador_de_Carga_R%C3%A1pida https://en.m.wikipedia.org/wiki/Acumulador_de_Carga_R%C3%A1p...
progfix 6y ago
> because physics dictates using hydrogen will always be much less efficient compared to direct electricity use You have to look at the whole system (and life-cycle) and not just compare single trains. I assume people with enough insight and expertise did the math and they don't just try this tech out for fun. EDIT: Also looking at the video, the giant transformators you usually have in a Lok aren't there. That weight difference already could make hydrogen competitive.

by hannob 6y ago

gsnedders 6y ago

There's plenty of train lines in the world that see very few trains, maybe only one an hour, where the business case for electrification is much weaker. Many of these lines are already questionable from a business case point of view which can deter anything that would increase infrastructure costs, and if hydrogen trains can approach the operational cost of electric trains then there's a clear business case for them.

hannob 6y ago
> if hydrogen trains can approach the operational cost of electric trains That's exceptionally unlikely. You go from "use electricity to run a train" to "use electricity to run an electrolyseur, fill hydrogen into hydrogen tanks on the train, use hydrogen to power a fuel cell to generate electricity, use that electricity to run a train".
- i_am_proteus 6y ago
  You need to add "build electric lines over entire length railway" to the left side of the equation and "build a hydrogen locomotive" to the right side.
- nine_k 6y ago
  Hydrogen is easier to store than electricity, and you can produce it at times where electricity price is zero or negative (very sunny days at photovoltaic plants, very windy days at wind turbine plants, 3am at nuclear plants). Processes more efficient than electrolysis do exist. I suppose safe storage and transportation of hydrogen is a major cost, though. Hydrogen gets absorbed into metals, because their crystalline lattices act like sponges for molecules this small. Worse yet, hydrogen can seep through things that work as impenetrable solids for other gases. And hydrogen flame is all but invisible (most radiation is infrared, nearly no visible light).
owenversteeg 6y ago
Yep. The trains in the article (Cuxhaven-Bremerhaven) go once per hour. That entire region of Germany, and the area of the Netherlands that borders it, has an enormous amount of trains running on a 1x/hourly schedule. Groningen-Leeuwarden, Groningen-Delfzijl etc etc. All running (diesel-electric) Stadler FLIRT trains, which have taken the world by storm. The political decisions in these less populated regions are similar to small town politics in two ways: the budgets are tiny (aka no money for electrification) and a fairly small group can push things through if it fits their agenda. For those reasons I think these hydrogen trains could totally become popular for less densely populated areas like this.
- tinus_hn 6y ago
  Just like just about every line in the Netherlands, there’s a train from Groningen to Leeuwarden and Delfzijl every 30 minutes.

pjc50 6y ago

The fixed cost and time consumption of electrification is quite high. I'm not sure about hydrogen specifically, but just as steam trains had a coal+water "tender" behind the engine, it seems not unreasonable to have a "battery" car on a train. Whether that's a tank of H2 or just a boxcar full of 18650 cells (anyone care to do the maths on that?)

Gibbon1 6y ago
I tried doing the math a few years ago. I did another search and up popped this. http://www.brooklynrail.net/science_of_railway_locomotion.html http://www.brooklynrail.net/science_of_railway_locomotion.ht... Which has the comment: At the same speed, same load (GCW) and on level ground, any steel wheeled railway vehicle is 24.6 times more energy efficient than any large rubber tire road vehicle, regardless of the type of power source. My hand wavy argument would be, to go 300 miles a passenger car needs 33% (guess) of it's weight to be batteries. But a truck is probably 2-2.5 times more efficient. So would only need 33% / 2.25 (split the middle between 2 and 2.5) or 15%. If a 4000 ton train is 25 times more effecient than a truck as started above then. 15%/25 is 0.6%. So the battery for a 4000 ton train would weigh 4000 * 0.6% -> 24 tons. Seems to pencil out to me.
- gsnedders 6y ago
  Note that the majority of hydrogen trains currently under development are all multiple units, and don't have dedicated locomotives. In the UK at least, track access charges push things towards distributed traction in part because of the axle loadings of any dedicated locomotive (or battery car). You see this to varying degrees across countries where speed is relevant. To take as an example: each British Class 802 motor car has a 1550 litre fuel tank. If we (slightly optimistically) assume the diesel engine is 50% efficient, and diesel fuel to have 10.8kWh/L energy density, then that's 8370kWh of energy produced. The Tesla 3 battery pack manages 160Wh/kg, so to carry 8370kWh the battery pack would be 52 tonnes. That's more than each car currently weighs in total. And a nine-car train has five such fuel tanks and engines.
  - 6y ago

globular-toast 6y ago

Overhead lines are an eyesore and third rails are dangerous. I wouldn't consider electrification the be all and all for railways. It comes with tradeoffs like anything else.

ben_w 6y ago
I’ve never understood the aesthetic argument given the railways themselves — and indeed major roads — are something I find extremely ugly.
- chrisseaton 6y ago
  You never understood why people think they’re ugly given that you think they’re ugly as well? What?
  - ben_w 6y ago
    I’ve never understood why electrification makes it worse when it’s ugly without, and when the alternatives are also ugly.
    - chrisseaton 6y ago
      The point is electrification via gantries makes it much more ugly. A railway line disappears into the ground somewhat, and to some people is actually attractive, even with emissions from a combustion engine. https://en.wikipedia.org/wiki/Glenfinnan_Viaduct https://en.wikipedia.org/wiki/Glenfinnan_Viaduct Electric gantries are seen to many people are far more intrusive to the landscape, and even destructive to landmarks, since they stick up into the air.
      - gsnedders 6y ago
        By way of comparison, the Royal Border Bridge, with relatively lightweight and specifically designed gantries: https://upload.wikimedia.org/wikipedia/commons/9/93/60163_Tornado_7_March_2009_Berwick.jpg https://upload.wikimedia.org/wikipedia/commons/9/93/60163_To...

tremon 6y ago

Passenger service is usually high-usage enough that the cost of electrification is worthwhile. But many freight-only lines still use diesel, even in areas where a majority of the rail net has been electrified, because little-used supply tracks lack an incentive to electrify them. If we can replace those diesel lines with hydrogen, that's a win. Also note that the motors themselves are electric, so when this train is running on an electrified section, it could still use the overhead lines. Not sure if modern diesel engines offer that same option (i.e. if the diesel is purely used as a generator for an otherwise electric engine).

tobylane 6y ago
Yes, all the diesel train engines are diesel-electric, and on some routes they use bi-mode (eg electric London to near Bristol, diesel-electric to Cardiff) trains.

MLR 6y ago

Something like 60% of the UK rail network is unelectrified and recent electrification projects have been ruinously expensive, we need something to fill in the gaps and hydrogen definitely has potential.

gsnedders 6y ago
> Something like 60% of the UK rail network is unelectrified and recent electrification projects have been ruinously expensive, we need something to fill in the gaps and hydrogen definitely has potential. It's not as bad as is often made out; with relatively few exceptions (GWML most prominently) most recent electrification programmes in the UK haven't been too much above European norms. In general, the reasons why costs have been higher in the UK are: * other countries having fairly constant ongoing electrification work leading to availability of skilled staff (versus massively spikes of electrification, then nothing for a decade or more), * many more structures (e.g., overbridges, tunnels) close to the limits of the loading gauge and hence more structures work needed * track access being more difficult in the UK (in general prolonged closures are harder to get approval for), and * operators being compensated for service disruption. At this point the UK really just needs an ongoing programme of electrification, as we now have high-quality modern off-the-shelf parts for most needs approved and in use on new projects, and we have designs that meet the requirements of almost all current routes. Also worth bearing in mind is the recently announced Scottish Government plan to decarbonise rail in Scotland by 2030, which includes electrifying all the major lines in Scotland. (A few won't be, and hydrogen trains have been mooted for them, but these are mostly lines with a few trains per day where the business case for electrification is always going to be weakest, especially combined with them often being in the most challenging terrain.)
fyfy18 6y ago
Have there been any experiements (on a long distance route) to have battery packs on trains that are fast-charged at stations? In the UK a lot of routes are at least partially electrified, and EV chargers have proved it is fairly easy to supply a few hundred kilowatt electric supply to urban areas. I know there are trams that work like this, but I'm wondering if the tech could be scaled up to trains. https://en.m.wikipedia.org/wiki/Acumulador_de_Carga_R%C3%A1pida https://en.m.wikipedia.org/wiki/Acumulador_de_Carga_R%C3%A1p...

progfix 6y ago

> because physics dictates using hydrogen will always be much less efficient compared to direct electricity use You have to look at the whole system (and life-cycle) and not just compare single trains. I assume people with enough insight and expertise did the math and they don't just try this tech out for fun. EDIT: Also looking at the video, the giant transformators you usually have in a Lok aren't there. That weight difference already could make hydrogen competitive.