Battery electric trains or Hydrogen Trains?

[TwistedMentat]

For freight it needs to be hydrogen. We could take a lesson from the steam era and carry the fuel in a tender behind the locomotive.

...
Current battery packs are down to 190 kg for 50 kwh, that would be a 75 ton battery!

An power plant weighs about 50t for the engine + alternator, plus 7t for the fuel.

So a battery is not a million miles away in weight! Cooling it might be another matter of course.
Cost, currently at £125/kwh = £2.5m, but is that so much more than a diesel / alternator set?

A class 66 that goes under the wires at any point (or the class 88) may not actually need such a large battery anyway!

Anyone with better figures out there?

A battery tender. That could be swapped out for a fresh battery.

 

[edwin_m]

While LNG has a greatly reduced carbon footprint v diesel, it is still a source of greenhouse gas emissions. Hydrogen is needed if the locomotive is to be zero carbon.

It's possible to harvest methane from sewage works and landfills, which has the double benefit of reducing consumption of other fuels and reducing the amount of methane that gets into the atmosphere (where it is more of a greenhouse gas molecule for molecule than CO2). Liquifying it would use a fair amount of energy but if that was also methane-powered it would remain carbon neutral or perhaps even carbon negative.

 

[DuncanD]

View attachment 45997
Only milk floats & mobility scooters can be battery operated. Image things as big as buses or trains?

Actually I have seen some of these DB Class 515 - and did travel on them quite a few times in my childhood days. So battery trains are nothing new - they do work. It is rather the price tag for the battery which was - and still is - prohibitive.

 

[hwl]

It's possible to harvest methane from sewage works and landfills, which has the double benefit of reducing consumption of other fuels and reducing the amount of methane that gets into the atmosphere (where it is more of a greenhouse gas molecule for molecule than CO2). Liquifying it would use a fair amount of energy but if that was also methane-powered it would remain carbon neutral or perhaps even carbon negative.

Which is already done by a firm in the UK that operates Bio-LNG refuel points in the UK (the biggest is at Daventry) with some of the big haulage firms as customers (Tesco, Sainsburys, Waitrose, B&Q, Coca Cola, DHL).

See: http://www.gasrec.co.uk/why/

 

[InTheEastMids]

Older UK locos hold about 3500 litres whereas a class 66 holds 6400 litres, hence a 66 would need a battery of around 20,000 kwh if no charging was possible all day.

Current battery packs are down to 190 kg for 50 kwh, that would be a 75 ton battery!

It's not just the weight, it's the size. I think a 10MW/5MWh battery needs 4 40ft ISO containers (which includes the power electronics), so the "tender" other people have mentioned could be much longer than the loco if the capacity will be 20 MWh - 4x larger than this. A future battery freight loco might look more like a 3 or 4 car EMU full of lithium.

Cost, currently at £125/kwh = £2.5m, but is that so much more than a diesel / alternator set?

At a basic pack cost, you're probably heading for the right ball-park. However, once you've added in power electronics, balance of plant, integration costs etc then you're looking at a much bigger number. I have some figures from last year that include all this in the context of utility battery systems and the number is North of £600 / kWh, although as I say, it's not a like-for-like comparison.

A class 66 that goes under the wires at any point (or the class 88) may not actually need such a large battery anyway!

Exactly, although the ability to put a cheap little diesel in an 88 makes that business case harder. You don't really care about the CO2 emissions from the diesel, or the cost of the fuel if it's only a small percentage of the total energy bill for the trip. Perhaps the first application is where somebody needs something like an 88, but that is fully zero-emissions, or needs full fat performance for a few km away from the wires.

 

[edwin_m]

Worth noting here that train length is constrained in the UK mostly by the lengths of available freight loops - most freight trains were historically fairly short and NR is pushed to lengthen them. So a couple of wagons' worth of batteries or gas tanks could mean loss of payload if the train is up against its length (or possibly weight) limit. This is a bit different from places like America and Russia where they have more scope to make the trains longer, as well as a larger structure gauge which reduces the length needed for a given volume.

 

[hwl]

Worth noting here that train length is constrained in the UK mostly by the lengths of available freight loops - most freight trains were historically fairly short and NR is pushed to lengthen them. So a couple of wagons' worth of batteries or gas tanks could mean loss of payload if the train is up against its length (or possibly weight) limit. This is a bit different from places like America and Russia where they have more scope to make the trains longer, as well as a larger structure gauge which reduces the length needed for a given volume.

LNG would only be 1 tanker wagon (which is enough to keep a pair of locos going on a transcontinental run and more in the States) why is why it is the most appealing of the alternative options to the UK FOCs.

 

[HSTEd]

The tanker might actually be fitted out as a "road slug" (in US parlance) - being fitted with traction motors powered by the attached unit.
That would enable it to generate tractive effort, especially when full.

Also worth noting that recuperated gas turbines are appearing with efficiencies north of 40% - which are still far more compact than diesels.
LNG is the perfect fuel for such an engine - which will would potentially allow high power electro....gas locomotives to be constructed.

 

[edwin_m]

The tanker might actually be fitted out as a "road slug" (in US parlance) - being fitted with traction motors powered by the attached unit.
That would enable it to generate tractive effort, especially when full.

Also worth noting that recuperated gas turbines are appearing with efficiencies north of 40% - which are still far more compact than diesels.
LNG is the perfect fuel for such an engine - which will would potentially allow high power electro....gas locomotives to be constructed.

Perhaps less relevant on a European mixed traffic railway where power is relatively more important. It probably doesn't matter in the States if you slog (or slug) up the hills at 5mph, but that's less of a possibility when there are passenger trains behind.

 

[The_Engineer]

See this presentation on Alstom's proposed Hydrogen powered train for the UK. 1000 kilometre range before refuelling, it carries a small battery for additional peak acceleration power and recapture of braking energy.
https://futureoftechnology.co.uk/video/moving-with-the-times-hydrogen-trains/
More in the times on how Alstom and Eversholt are working together to make a UK version of the technology.
https://www.thetimes.co.uk/article/hydrogen-fuel-cell-trains-herald-new-steam-age-mdf78f2dk

 

[InTheEastMids]

Just came across these slides which have some interesting consensus forecasts about battery development in terms of high-level KPIs. Time to get out the beermats/fag-packets...

https://www.apcuk.co.uk/app/uploads/2018/02/EES_Full_Pack.pdf

 

[D365]

Just came across these slides which have some interesting consensus forecasts about battery development in terms of high-level KPIs. Time to get out the beermats/fag-packets...

https://www.apcuk.co.uk/app/uploads/2018/02/EES_Full_Pack.pdf

What does "KPI" stand for please?

Personally I believe that until a serious viable alternative for energy storage is developed, lithium-ion technology will continue to be the preferred medium. As an indication of the progress that has been made in the last decade, Tesla/Panasonic batteries have an energy density more than twice that of the Valence "U-Charge" type used in the Class 379.

 

[Shaw S Hunter]

What does "KPI" stand for please?

KPI = Key Performance Indicators, a favourite term in management speak.

 

[Andy25]

Hydrogen's too dangerous, you'd be better off using steam or bionic duckweed...

Dangerous how? Used in buses in London without issue

 

[HSTEd]

Hydrogen is a terrible fuel for things that move.
It's energy density once you include things like tanks is absolutely terrible.

Much better to use things like dimethyl ether and the like.

 

[Thunderer]

Stick to coventional 25KV overhead lines. Tried and tested. All this Hydrogen and Battery nonsense Alternative technology is not developed enough yet to implement as reliable and that comes at a huge cost to anyone thinking of using this new technology to power something as big as a train. Instead of daft DFT cancelling electrification projects, it should be rolled out on a much bigger scale. GWR will end up with a half arsed job thanks to the DFT. Wires should have been put up as planned to Swansea, Bristol Parkway to Exeter and Reading to Exeter should have been electrified, thus making great use of 800/802

 

[D365]

All this Hydrogen and Battery nonsense Alternative technology is not developed enough yet to implement as reliable and that comes at a huge cost to anyone thinking of using this new technology to power something as big as a train.

I’m sorry that you think our self-powered rolling stock R&D studies are a waste of time.

 

[Thunderer]

I’m sorry that you think our self-powered rolling stock R&D studies are a waste of time.

Its certainly not a waste of time, all research and study is valuable, but for me I don't really see the point for this for the railways when the answer is already there..25Kv..just need more of it. Those technologies (battery/hydrogen) are more associated with road vehicles and personally, thats where I think this technology fits perfectly.

 

[D365]

I’d love it if 25kV was a perfect answer. The problem isn’t the electrical costs, it’s the civils involved in enabling overheads to be put up.

 

[superkev]

I'm puzzled where all this hydrogen is going to come from. The current bulk technology is steam reforming of natural gas at around £10 a litre which is hardly green or economic. Electrolysis is even less efficient Roger Ford of modern railways quoting an overall efficiency to wheel of only 30% compared with 80% for electrification.
K

 

[Shaw S Hunter]

People can be as sceptical as they like but hydrogen powered trains are being ordered in various places and there is growing interest in the concept generally.

Zillertalbahn in Austria has ordered 5 HMUs as an alternative to electrification: http://www.railwaygazette.com/news/...upplier.html?sword_list[]=hydrogen&no_cache=1

14 HMUs have been ordered by the Niedersachsen transport authority for use in far North-West Germany: https://www.globalrailnews.com/2017...order-for-its-hydrogen-powered-coradia-ilint/

Rhein-Main transport authority is tendering for (likely) 26 HMUs for its Taunus regional network: https://www.railjournal.com/index.p...g-begins-for-german-hydrogen-train-order.html

The province of Ontario is seriously considering hydrogen power as an alternative to electrification for its future RER style network: http://www.railwaygazette.com/news/...y-finds.html?sword_list[]=hydrogen&no_cache=1

I would suggest that already it is the case that it's the economics of hydrogen fuel production and distribution that is the limiting factor to its wider adoption rather than any significant technical concerns.

 

[gingertom]

People can be as sceptical as they like but hydrogen powered trains are being ordered in various places and there is growing interest in the concept generally.

Zillertalbahn in Austria has ordered 5 HMUs as an alternative to electrification: http://www.railwaygazette.com/news/...upplier.html?sword_list[]=hydrogen&no_cache=1

14 HMUs have been ordered by the Niedersachsen transport authority for use in far North-West Germany: https://www.globalrailnews.com/2017...order-for-its-hydrogen-powered-coradia-ilint/

Rhein-Main transport authority is tendering for (likely) 26 HMUs for its Taunus regional network: https://www.railjournal.com/index.p...g-begins-for-german-hydrogen-train-order.html

The province of Ontario is seriously considering hydrogen power as an alternative to electrification for its future RER style network: http://www.railwaygazette.com/news/...y-finds.html?sword_list[]=hydrogen&no_cache=1

I would suggest that already it is the case that it's the economics of hydrogen fuel production and distribution that is the limiting factor to its wider adoption rather than any significant technical concerns.

there is a place for hydrogen, with all its limitations. It is not suitable as power source for high power applications: fast passenger and heavy freight. Those will remain in the capable hands of diesel and electric.

 

[K.o.R]

Its certainly not a waste of time, all research and study is valuable, but for me I don't really see the point for this for the railways when the answer is already there..25Kv..just need more of it. Those technologies (battery/hydrogen) are more associated with road vehicles and personally, thats where I think this technology fits perfectly.

I've said before that the solution is clearly chicken-wire strung up over all the roads and a dodgem-car pole attached to every vehicle.

 

[gingertom]

I've said before that the solution is clearly chicken-wire strung up over all the roads and a dodgem-car pole attached to every vehicle.

but not in areas of outstanding natural beauty, one of Chris Grayling's reasons for cancelling Windermere's OLE.

 

[Shaw S Hunter]

there is a place for hydrogen, with all its limitations. It is not suitable as power source for high power applications: fast passenger and heavy freight. Those will remain in the capable hands of diesel and electric.

For fast/high-speed passenger I think you're probably right, as in electrified lines is what makes sense. For heavy freight the argument is less clear cut. Given the increasing demands to phase out diesel things are bound to change. Hydrogen is unlikely to scale up to heavy haul but cleaner burning CNG/LNG could be a viable alternative. And for freight trains the need to carry additional fuel, whether in a dedicated tender or as part of the train, is not really an issue: trans-continental freights in Australia already do this with diesel (and water).

 

[xotGD]

For fast/high-speed passenger I think you're probably right, as in electrified lines is what makes sense. For heavy freight the argument is less clear cut. Given the increasing demands to phase out diesel things are bound to change. Hydrogen is unlikely to scale up to heavy haul but cleaner burning CNG/LNG could be a viable alternative. And for freight trains the need to carry additional fuel, whether in a dedicated tender or as part of the train, is not really an issue: trans-continental freights in Australia already do this with diesel (and water).

A tender full of hydrogen would work just fine for freight. Or indeed loco-hauled stock on passenger services.

 

[Shaw S Hunter]

A tender full of hydrogen would work just fine for freight. Or indeed loco-hauled stock on passenger services.

The problem being that individual fuel-cell units of a rail-suitable size produce only enough power to drive one or two vehicles, fine for passenger units but not for freight. BNSF have a single hydrogen powered switcher working in California as part of a Department of Defense(!) sponsored research project which has been going on for 9 years already. Alstom are planning on building hydrogen powered locos in (and for) India but the power output is only about 300kw, fine for shortish local stopping trains but nothing more. For higher output non-electric locomotives internal combustion remains the only viable method of power generation but that doesn't have to be diesel. And using hydrogen for internal combustion is fraught with huge difficulties compared with CNG/LNG.

 

[randyrippley]

I can't help thinking that if hydrogen is the way forward, then you'd get a better power/weight ratio by using a small gas turbine rather than an internal combustion engine. You'd have to use battery/capacitor storage to maximise efficiency so the turbine runs at constant speed. But it should still be lighter than a modified petrol engine. Remember not a lot of research has gone into large spark plug engines in recent years: hydrogen isn't going to work in a diesel. If you're going to design a new range of engines you might as well go for turbines.
What happened to the small Rover units used in the APT-E?

 

[James James]

I can't help thinking that if hydrogen is the way forward, then you'd get a better power/weight ratio by using a small gas turbine rather than an internal combustion engine. You'd have to use battery/capacitor storage to maximise efficiency so the turbine runs at constant speed. But it should still be lighter than a modified petrol engine. Remember not a lot of research has gone into large spark plug engines in recent years: hydrogen isn't going to work in a diesel. If you're going to design a new range of engines you might as well go for turbines.
What happened to the small Rover units used in the APT-E?

BTW, hydrogen isn't used like a conventional "fuel":
https://en.wikipedia.org/wiki/Fuel_cell

Essentially you'll have an electric train, with a hydrogen fuel cell providing the electricity instead of catenary (or a diesel engine + generator).

 

[edwin_m]

I can't help thinking that if hydrogen is the way forward, then you'd get a better power/weight ratio by using a small gas turbine rather than an internal combustion engine. You'd have to use battery/capacitor storage to maximise efficiency so the turbine runs at constant speed. But it should still be lighter than a modified petrol engine. Remember not a lot of research has gone into large spark plug engines in recent years: hydrogen isn't going to work in a diesel. If you're going to design a new range of engines you might as well go for turbines.
What happened to the small Rover units used in the APT-E?

The conclusion in the 1970s was that gas turbine wasn't suitable for rail, due to the fuel consumption on idle being nearly as much as on full power. Trains have intermittent bursts of full power when accelerating but most of the time are at a lower power level. There was some fleet service of Turbotrains, notably in France, but once the oil crisis hit in 1974 it was always unlikely any more would be built.

From what I can tell a fuel cell has a related problem, that isn't good at changing power output quickly. So (unless the gas turbine has improved drastically). either would need to be "hybridised" with a bank of batteries or supercapacitors so that the prime mover could run moreorless constantly, storing the energy when not immediately needed to give a boost during acceleration.