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Bombardier are currently trialling one or two trains with this setup, but at the moment the sheer weight of batteries required to make 300 tonnes plus of train move is...well, a hell of a lot. I can't imagine it being cheap either, and I can't see batteries powering trains at 125/155/185mph including all the acceleration (regenerative braking already exists on trains) for too long. You'd need a hell of a charger.
Not all trains are long distance intercity trains driving at those speeds over long distances...

The Diesel electric train I used to catch into Glasgow Central peaked out at about 65 mph, (measured with GPS) and had a 50 mile round trip from the main station to its furthest destination and back again where it would sit at the main station for a good 20 minutes before setting out again.

Seems like a candidate for a battery / overhead lines electric only implementation. You say you'd need "a hell of a charger", but that's a "we can only charge stopped at the platform" mentality.- what if each stop, plus a couple of miles of lines on either side of each stop was electrified but the main portion of the line out in the intervening countryside wasn't ?

As long as the ratio of charging rate and charging line length vs discharge rate and total journey length was sufficiently high it would work - no need to electrify the entire line.

Something similar is already being done with buses with overhead inductive charging at each stop - it would be easier to do it in the train scenario to be honest, as most lines are already at least partially electrified.

By the way are you sure all Diesel Electric trains have regenerative braking ? I've had a pretty good look at the generator cars on the one I used to catch and didn't see anything looking like batteries. Another dead giveaway is that the Diesel engine always revs up to high revs before the train starts moving then throttles back once it's up to speed.

If it had regenerative braking (and/or any charging of surplus energy from the generator into a battery) it should have enough energy stored in the battery to accelerate the train from a standstill without revving up the Diesel generator, and just use it like a Rex. But from observing the behaviour of the trains day after day this is not happening. The Diesel engine is always revving up just before some acceleration.

I don't believe any of the Diesel Electric trains I caught from Glasgow central had regenerative braking, or indeed any batteries. Just a directly supply from the generator set to the electric motors and normal friction brakes for stopping.
 

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Bombardier are currently trialling one or two trains with this setup, but at the moment the sheer weight of batteries required to make 300 tonnes plus of train move is...well, a hell of a lot. I can't imagine it being cheap either, and I can't see batteries powering trains at 125/155/185mph including all the acceleration (regenerative braking already exists on trains) for too long. You'd need a hell of a charger.
Batteries (and hydrogen) are pointless for a high speed/high density operation, where existing wired approaches are more cost effective than carrying around the power source.

The place where a new solution is needed is secondary lines with relatively infrequent services such that the investment in electric wiring is out of proportion to the cost of the trains and so can’t be justified. These tend to be lower speed anyhow (if you can afford high speed infrastructure then the level of demand must be high already, tilting the balance away from on-board power).

The guys at Vivarail (who are building low-cost trains for secondary lines by re-engineering redundant electric stock) have a proposition with 208kWh of batteries (two 104kWh packs) under each carriage, in conjunction with a fast charger that can add 40 miles of range in 8 minutes or 50 miles in 10 minutes. This can hence shuttle to and fro all day on a branch line of up to 50 miles long, charging during the turnaround time at each end.
 

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By the way are you sure all Diesel Electric trains have regenerative braking ?
Many do - but not in the sense implied here.

They regenerate and burn the power in large resistors (typically on the roof).

When first introduced, this was seen as a great improvement, since changing brake pads on standard disc-braked high speed stock was one of the heaviest maintenance requirements and this got rid of a lot of the brake pad wear. Does nothing for energy efficiency of course.

Even on electric stock, regen has been relatively late to get introduced and is still not enabled everywhere in the UK: it needs both capable trains and infrastructure able to accept the input, and there are stll plenty of examples of both that can’t do it.
 

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Many do - but not in the sense implied here.

They regenerate and burn the power in large resistors (typically on the roof).

When first introduced, this was seen as a great improvement, since changing brake pads on standard disc-braked high speed stock was one of the heaviest maintenance requirements and this got rid of a lot of the brake pad wear. Does nothing for energy efficiency of course.
Still not regenerative braking by any normal definition if the energy isn't actually stored and re-used.
Even on electric stock, regen has been relatively late to get introduced and is still not enabled everywhere in the UK: it needs both capable trains and infrastructure able to accept the input, and there are stll plenty of examples of both that can’t do it.
Instead of a needlessly complicated system of trying to inject regenerative braking power back into the overhead supply lines, why not just fit a small battery like you would in a hybrid car that is big enough to store regenerative braking energy for re-use and not much bigger ?

Seems a lot less complex that basically trying to supply that short burst of energy back into the grid ?
 

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Batteries (and hydrogen) are pointless for a high speed/high density operation, where existing wired approaches are more cost effective than carrying around the power source.
Route electrification has proven extremely expensive in many cases. Just look at Network Rail's attempts to electrify the Great Western main line. Years late, billions over budget, and now parts of it have been deferred for years or cancelled entirely because it just costs too much.

It's not stringing up wires that's the difficult part - it's lowering the trackbed under bridges, digging out tunnels, etc to create the increased clearances needed for overhead wires. And in some cases, just getting the power supply in to remote areas in the first place.

The government's solution is to deploy hybrid diesel-electric trains that can run on electric under the wires, and then switch to diesel on un-electrified parts of the network. But diesel hybrid trains still suffer from the same problems as all diesel trains: high maintenance and fuel costs, noise, and pollution.

But what if you could lower the costs of electrification by only installing wires on the parts of the line where it is cost-effective and needed most? Where the track goes under bridges, through tunnels, through remote off-grid areas, scenic areas where you don't want the wires spoiling the view, etc the trains would switch to battery power. The batteries would only need to be big enough to handle the longest section of un-electrified track, not power the train for the entire journey!

Likewise, battery trains would be perfect for routes where most of the length is along an electrified main line, but terminating on an unnelectrified branch line. The costs of the batteries would be much, much less than the costs to electrify the branch!
 

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Route electrification has proven extremely expensive in many cases. Just look at Network Rail's attempts to electrify the Great Western main line. Years late, billions over budget, and now parts of it have been deferred for years or cancelled entirely because it just costs too much.

It's not stringing up wires that's the difficult part - it's lowering the trackbed under bridges, digging out tunnels, etc to create the increased clearances needed for overhead wires. And in some cases, just getting the power supply in to remote areas in the first place.

The government's solution is to deploy hybrid diesel-electric trains that can run on electric under the wires, and then switch to diesel on un-electrified parts of the network. But diesel hybrid trains still suffer from the same problems as all diesel trains: high maintenance and fuel costs, noise, and pollution.

But what if you could lower the costs of electrification by only installing wires on the parts of the line where it is cost-effective and needed most? Where the track goes under bridges, through tunnels, through remote off-grid areas, scenic areas where you don't want the wires spoiling the view, etc the trains would switch to battery power. The batteries would only need to be big enough to handle the longest section of un-electrified track, not power the train for the entire journey!

Likewise, battery trains would be perfect for routes where most of the length is along an electrified main line, but terminating on an unnelectrified branch line. The costs of the batteries would be much, much less than the costs to electrify the branch!
I would imagine that a train capable of 5 miles at full speed on battery would be as cheap, or cheaper than hybrid diesel-electric, and would make electrifying lines considerably cheaper!
 

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You aren't ever going to get the lines up in the Highlands or Wales electrified. There simply isn't a business case for it.
The costs of electrification are just incredibly high, let alone the costs of new rolling stock.

Here in Sheffield we still use Pacer trains very heavily - those awful freight wagon/Leyland bus hybrid!

Maybe batteries for shorter range shuttle trains, but (sorry to say) that H2 is quite a good solution for longer routes. So long as you can generate the H2 at the depot via the use of PV/wind, then it's a compromise worthy of investigation.

When battery tech is much better than now, we can simply junk the fuel cells and replace with a battery pack!
 

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Oh, and more utter hilarity; unless I am very much mistaken, there are a couple of enormous Aggreko diesel generators (shipping container size) outside ITM's office, seeming supplying power to an electrolyser.

Talk about an expensive and inefficient way to make H2...
 

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Discussion Starter #136
Look what I found at Gatwick this week. Another station that won’t get used very much.


Maybe it can be turned into a rapid charger site for EVs in a few years...


Sent from my iPhone using Tapatalk
 

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Look what I found at Gatwick this week. Another station that won’t get used very much.
Nah I'm sure there is a queue of cars backed up the street waiting to use it as soon as those cones are removed. :D
 

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Only one car at a time. I wonder how much that cost!
 

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Someone somewhere is making a ton of money off this somehow... I'm just not sure how or who it could be. Government grants are likely involved though.

I'm not even mad I just wish it was me!
 
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