Ideas for Recharging battery trains

[Nottingham59]

What are the practical methods for recharging battery-powered trains? In the most straightforward case, the battery train will have a long run under the wires (or on third rail) before reaching a short unelectrified section. This might apply to the Windermere branch, or Matlock after MML electrification.

But most cases will require some other form of power supply to recharge the batteries.

This article reports a short OHLE bus bar at a terminus station:

Fast charging for battery trains successfully tested in Germany

The rapid charging station for battery trains Voltap has passed its technical baptism of fire. A battery train from Stadler Rail was successfully charged with Voltap, developed by Swiss catenary specialist Furrer + Frey and local utility company Stadtwerke Tübingen. Charging with Voltap takes...

www.railtech.com

("Charging with Voltap takes place without a socket or plug. Although the point of a battery trains is that it can run on non-electrified lines, it is charged via its pantograph at an overhead line system, which together with a transformer station forms the rapid charging station. However, the rest of a line then does not need to have an overhead line to be operated with electric trains.")
This approach would be simple, but I can see all sorts of problems with unbalanced phases, and a static frequency converter (SFC) would be hugely expensive just to recharge trains at, say, Oban.

Vivarail claim they can recharge 600kWh 3-car train in 10 minutes, using their proprietary system. See here: https://vivarail.co.uk/cop26-battery-train-makes-the-evening-news/ (video) and here https://www.railjournal.com/technology/vivarail-shows-off-battery-train-at-cop26/ ("The three-car former London Underground class 230 D-Train used to demonstrate battery power in Scotland is fitted with six batteries ....Vivarail’s Fast Charge system which can fully recharge the train in 10 minutes.")
I can see that sort of approach working at places like Uckfield, and thus saving the cost and risks of extending third rail electrification.

Ionity super-fast car chargers now being able to deliver 350kW at the kerbside. Would it be feasible to use that technolgy to recharge battery trains at terminating stations like Oban? 350kW would recharge a Vivarail class 230 in half an hour, giving a claimed 100 mile range.

Any thoughts?

 

[wobman]

What are the practical methods for recharging battery-powered trains? In the most straightforward case, the battery train will have a long run under the wires (or on third rail) before reaching a short unelectrified section. This might apply to the Windermere branch, or Matlock after MML electrification.

But most cases will require some other form of power supply to recharge the batteries.

This article reports a short OHLE bus bar at a terminus station:

Fast charging for battery trains successfully tested in Germany

The rapid charging station for battery trains Voltap has passed its technical baptism of fire. A battery train from Stadler Rail was successfully charged with Voltap, developed by Swiss catenary specialist Furrer + Frey and local utility company Stadtwerke Tübingen. Charging with Voltap takes...

www.railtech.com

("Charging with Voltap takes place without a socket or plug. Although the point of a battery trains is that it can run on non-electrified lines, it is charged via its pantograph at an overhead line system, which together with a transformer station forms the rapid charging station. However, the rest of a line then does not need to have an overhead line to be operated with electric trains.")
This approach would be simple, but I can see all sorts of problems with unbalanced phases, and a static frequency converter (SFC) would be hugely expensive just to recharge trains at, say, Oban.

Vivarail claim they can recharge 600kWh 3-car train in 10 minutes, using their proprietary system. See here: https://vivarail.co.uk/cop26-battery-train-makes-the-evening-news/ (video) and here https://www.railjournal.com/technology/vivarail-shows-off-battery-train-at-cop26/ ("The three-car former London Underground class 230 D-Train used to demonstrate battery power in Scotland is fitted with six batteries ....Vivarail’s Fast Charge system which can fully recharge the train in 10 minutes.")
I can see that sort of approach working at places like Uckfield, and thus saving the cost and risks of extending third rail electrification.

Ionity super-fast car chargers now being able to deliver 350kW at the kerbside. Would it be feasible to use that technolgy to recharge battery trains at terminating stations like Oban? 350kW would recharge a Vivarail class 230 in half an hour, giving a claimed 100 mile range.

Any thoughts?

This may be a better option for the tfw 230's instead of them being diesel hybrid units, they can recharge at Bidston and then install a small 3rd rail section at Wrexham general p4 to central.

 

[Ken H]

I am probably out of date with battery technology, but doesnt fast charging heat up the battery damaging it, and thus, shortening its life.
And delivering 350Kw in a small town may be difficult without major upgrade to the local network. Especially when you want 350Kw for a short time then a long period of no load. Most infrastructure is based on a constant load, not having big local spikes.

 

[D365]

The selling point of the Vivarail system is that, save for the driver ”activating” the system from the cab, it’s entirely automated. No need to plug or unplug the train.

 

[Skie]

The Merseyrail expectations for Bidston to Wrexham, based on their battery trials, are 2 or 3 charging points at intermediate stops. The 777s would just need a slightly longer dwell time to top up the battery. A full lap of the loop is then enough to fully charge the battery ready for the next stint off the 3rd rail.

I am probably out of date with battery technology, but doesnt fast charging heat up the battery damaging it, and thus, shortening its life..

Modern cooling systems help mitigate the issue almost completely. Tesla pioneered pumping coolant around their batteries, radiators and their electric motors so they can warm cold batteries and cool hot ones. Modern battery trains will be doing something similar though likely not using the traction motors to avoid too much complexity but sacrificing a bit of efficiency.

 

[swt_passenger]

I am probably out of date with battery technology, but doesnt fast charging heat up the battery damaging it, and thus, shortening its life.
And delivering 350Kw in a small town may be difficult without major upgrade to the local network. Especially when you want 350Kw for a short time then a long period of no load. Most infrastructure is based on a constant load, not having big local spikes.

IIRC Vivarail’s idea was to install another large battery at the charging point, and charge it gradually off the distribution network. Then discharge it into the train. Just seems like another source of significant charge/discharge losses.

 

[snowball]

IIRC Vivarail’s idea was to install another large battery at the charging point, and charge it gradually off the distribution network. Then discharge it into the train. Just seems like another source of significant charge/discharge losses.

However, in return for that, it does remove the need for a high-capacity mains connection to the charging site. That might make all the difference to the practicality of using battery trains on a rural route. As I mentioned in another thread, I believe Vivarail studied the West Highland Lines and concluded that charging sites at Crianlarich, Oban, Fort William and Mallaig (plus, presumably, the ability to charge from the wires between Glasgow and Craigendoran) would be enough.

 

[D365]

IIRC Vivarail’s idea was to install another large battery at the charging point, and charge it gradually off the distribution network. Then discharge it into the train. Just seems like another source of significant charge/discharge losses.

Yes but what’s the alternative?

 

[D821]

We discussed something similar in another thread back in September:

BEMUs and on-route charging

I've been following Merseytravel's proposals to run some of their new Class 777 EMUs with batteries to serve a new station at Headbolt Lane, Kirby and possibly Wrexham. Is it worth having 3rd rails at stations on non-electrified sections of route or does the the short dwell time not make it...

www.railforums.co.uk

 

[swt_passenger]

Yes but what’s the alternative?

Proper electrification would be my suggestion…

 

[GRALISTAIR]

Proper electrification would be my suggestion…

You and me both.

 

[InOban]

However, in return for that, it does remove the need for a high-capacity mains connection to the charging site. That might make all the difference to the practicality of using battery trains on a rural route. As I mentioned in another thread, I believe Vivarail studied the West Highland Lines and concluded that charging sites at Crianlarich, Oban, Fort William and Mallaig (plus, presumably, the ability to charge from the wires between Glasgow and Craigendoran) would be enough.

Scogov are planning hydrogen trains for the WHL. One of the windpower companies is planning an electrolysis site in Oban, partly to replace some of the town gas supply.

 

[D365]

Proper electrification would be my suggestion…

Absolutely, yes. But for rural lines with 1tp2h or less, when will that happen...

 

[Nottingham59]

Proper electrification would be my suggestion

But that doesn't make economic sense for fewer than around six trains per hour. Though I can see the argument for discontinuous electrification in places where it is easy, to allow battery trains to recharge on the move

 

[bavvo]

Yes but what’s the alternative?

I think the easiest way, if you are designing a system from scratch would be as follows. Design a train with a compartment at one end with wide access doors. Create a battery pack sufficient to propel the train that is mounted on a industy standard pallet. This can then be loaded at the platform at the start or end of the route, or at intermediate stations as needed. Once the battery needs recharging it would be swapped out for a fully charged one, and then can be trickle charged at the station until needed again. You might need a slightly longer train/platforms for this, and probably a forklift to move a ton of battery, but its still fairly low tech and acheivable, and probably a lot cheaper than for instance, wiring the whole West Highland line.

 

[Irascible]

I think the easiest way, if you are designing a system from scratch would be as follows. Design a train with a compartment at one end with wide access doors. Create a battery pack sufficient to propel the train that is mounted on a industy standard pallet. This can then be loaded at the platform at the start or end of the route, or at intermediate stations as needed. Once the battery needs recharging it would be swapped out for a fully charged one, and then can be trickle charged at the station until needed again. You might need a slightly longer train/platforms for this, and probably a forklift to move a ton of battery, but its still fairly low tech and acheivable, and probably a lot cheaper than for instance, wiring the whole West Highland line.

While that's a simple idea & it's possible some variation might work, the safety case might like a word... a ton of fully charged battery ought to be handled with some care, let's say.

Local electricity storage piles are not the worst idea even if you don't want to fast-charge a train, really.

 

[D365]

I think the easiest way, if you are designing a system from scratch would be as follows. Design a train with a compartment at one end with wide access doors. Create a battery pack sufficient to propel the train that is mounted on a industy standard pallet. This can then be loaded at the platform at the start or end of the route, or at intermediate stations as needed. Once the battery needs recharging it would be swapped out for a fully charged one, and then can be trickle charged at the station until needed again. You might need a slightly longer train/platforms for this, and probably a forklift to move a ton of battery, but its still fairly low tech and acheivable, and probably a lot cheaper than for instance, wiring the whole West Highland line.

The difficuly I see is that it would be very difficult to automate this process. And even if that were possible, you’d need to convince the ORR that the hazards introduced by this process are suitably managed.

 

[Bald Rick]

There are a number of companies trying to sell proprietary charging kit, which of course then ties you into their system. It seems odd to provide a new type of automatic system for transferring electrical power from a lineside system to a train, when we already have two, the most popular of which which can transfer 16MW without difficulty.

IIRC Vivarail’s idea was to install another large battery at the charging point, and charge it gradually off the distribution network. Then discharge it into the train. Just seems like another source of significant charge/discharge losses.

This has always been the plan for battery train proposals needing a recharge anywhere remote from a decent power supply. I had exactly the same question about charge / discharge losses ... right up to the point that the electrical engineer concerned then walked me through the evidence that demonstrated the end to end losses were somewhat less than a standard third rail distribution system (My A Level physics was not a patch on his CEng).

While that's a simple idea & it's possible some variation might work, the safety case might like a word... a ton of fully charged battery ought to be handled with some care, let's say.

A 500 kWh battery back, sufficient to power (say) a 4 car unit for 70-80 miles, would be the thick end of 3-4 tonnes; double that for a Lithium titanate battery that is more suited to rail application.

 

[bavvo]

A 500 kWh battery back, sufficient to power (say) a 4 car unit for 70-80 miles, would be the thick end of 3-4 tonnes; double that for a Lithium titanate battery that is more suited to rail application.

Thats kind of my point with a swappable battery pack. You have a smaller one suitable for 15-20 miles, and swap it out en-route rather than lug the whole lot all the way. There is obviously a trade off between weight of battteries carried, range, and time needed to swap the units. Complete speculation here, but I imagine an electric train with a small battery swapped at intervals could perform similar timings to current diesal DMUs.

 

[gordonthemoron]

Like the trams in Newcastle NSW? These have charging points at each stop (aside from Newcastle Interchange and the adjacent depot which have OHLE) and they recharge through the pantograph

 

[Bald Rick]

Thats kind of my point with a swappable battery pack. You have a smaller one suitable for 15-20 miles, and swap it out en-route rather than lug the whole lot all the way. There is obviously a trade off between weight of battteries carried, range, and time needed to swap the units. Complete speculation here, but I imagine an electric train with a small battery swapped at intervals could perform similar timings to current diesal DMUs.

trust me, it’s a lot easier to have a bigger battery and charge it when you can.

 

[CdBrux]

You and me both.

meanwhile, back in the real world...

 

[GRALISTAIR]

meanwhile, back in the real world...

batteries are going to be a big chunk of the solution...

 

[John R]

Thats kind of my point with a swappable battery pack. You have a smaller one suitable for 15-20 miles, and swap it out en-route rather than lug the whole lot all the way. There is obviously a trade off between weight of battteries carried, range, and time needed to swap the units. Complete speculation here, but I imagine an electric train with a small battery swapped at intervals could perform similar timings to current diesal DMUs.

So, three swaps between Crianlarich and Fort William? That doesn't sound the most practical solution to me.

 

[CdBrux]

batteries are going to be a big chunk of the solution...

Quite, and if can be done with a non perfect, but perfectly good enough, solution at a far lower cost (and quicker in terms of time needed to design and install the solutions) then can be very promising

 

[Nicholas Lewis]

So, three swaps between Crianlarich and Fort William? That doesn't sound the most practical solution to me.

No converting it to diesel hybrid battery is the most sensible option given its a handful of trains its emissions are more than capable of being offset. There is still embedded emissions associated with creating batteries in the first place along with supporting charging infrastructure.

 

[Irascible]

Eventually we might get to the point where we only need occasional combustion engine use & the demand is low enough that we can run them on biofuels of some sort ( piston engines & even more so gas turbines are pretty flexible devices, just needs something that heats air & burns somewhat controllably & preferably evenly ) - and if you're only doing it occasionally for some of these edge cases that aren't going to be wired & are a bit awkward for batteries, fuel economy starts becoming a bit less important because there's no scale up, so you can ladle on exhaust cleansers & noise reduction too.

We might also get a new wonder-battery that doesn't use awkward rare metals, has the energy density of hydrocarbons & charges as fast as you can supply power. Lots of interesting patents being taken out, waiting for practical applications. I think at some point the battery is going to end up a structural part of any electric vehicle which does rather preclude swapping it...

 

[Nicholas Lewis]

Eventually we might get to the point where we only need occasional combustion engine use & the demand is low enough that we can run them on biofuels of some sort ( piston engines & even more so gas turbines are pretty flexible devices, just needs something that heats air & burns somewhat controllably & preferably evenly ) - and if you're only doing it occasionally for some of these edge cases that aren't going to be wired & are a bit awkward for batteries, fuel economy starts becoming a bit less important because there's no scale up, so you can ladle on exhaust cleansers & noise reduction too.

Its the only practical way to keep the more remote lines going. A few diesel engines preferably with a hybrid battery to recuperate braking energy is hardly going to even be measurable.

We might also get a new wonder-battery that doesn't use awkward rare metals, has the energy density of hydrocarbons & charges as fast as you can supply power. Lots of interesting patents being taken out, waiting for practical applications. I think at some point the battery is going to end up a structural part of any electric vehicle which does rather preclude swapping it...

Thats always a possibility but there has been no major commercialisation of any new battery technology since Lithium well over 25 years ago so it can't be banked upon.

 

[Bald Rick]

Thats always a possibility but there has been no major commercialisation of any new battery technology since Lithium well over 25 years ago so it can't be banked upon.

Indeed, but the prize for the winner is spectacular, so as you can imagine there is a lot of money being invested in the various new battery technologies in a race to commercialise them. Might be a decade away, but so was commercialisation of electric cars, 9 years ago..

 

[Nicholas Lewis]

Indeed, but the prize for the winner is spectacular, so as you can imagine there is a lot of money being invested in the various new battery technologies in a race to commercialise them. Might be a decade away, but so was commercialisation of electric cars, 9 years ago..

Indeed and should a super battery materialise all to the good for the human race but to steal Roger Fords phrase Bionic Duckweed coming good in a decade is a risky strategy currently in addressing emission reduction although my review remains that a dozen or so diesel-hybrids travelling around rural Scottish lines isn't going to even register on any global measuring system.