Do IPEMUs mean the End of Electrification?

[JohnElliott]

There's an interview in today's Times with Mark Carne, suggesting the answer's "yes". I've only got a paywalled link: Run trains on batteries, says Network Rail boss.

He seems to be of the view that the future lies with batteries and bimodes (with a mention of hydrogen or LPG as alternatives to diesel).

 

[najaB]

He seems to be of the view that the future lies with batteries and bimodes (with a mention of hydrogen or LPG as alternatives to diesel).

I've not read the article, but it's slightly worrying that someone who should have at least a basic understanding of engineering doesn't seem to appreciate that the energy density of diesel is many times that of hydrogen or LPG. What works for a family car or light delivery van doesn't scale up to trains that need to accelerate several hundred tons to 125mph and back down to a stop repeatedly and continuously over the course of 16+ hours a day.

 

[swt_passenger]

I thought his organisation's recent Kent Route Study had already poured cold water on battery EMUs?

 

[snowball]

Perhaps he needs something else to enthuse over now the 40% capacity increase from the Digital Railway has been debunked.

 

[The Ham]

There's an interview in today's Times with Mark Carne, suggesting the answer's "yes". I've only got a paywalled link: Run trains on batteries, says Network Rail boss.

He seems to be of the view that the future lies with batteries and bimodes (with a mention of hydrogen or LPG as alternatives to diesel).

Personally I think that there is a case for a lot of what would otherwise be infill schemes to use Bi-modals trains for the time being. This would free up resources to put wires up on key trunk routes and high frequency metro services.

However over time I would expect that electrification would continue, however I would guess Carne's comments could well be to manage people's expectations as to what the HLOS is likely to be presenting for the next CP.

 

[Taunton]

I would guess Carne's comments could well be to manage people's expectations as to what the HLOS is likely to be presenting for the next CP.

I am sure that in the NR/TOC split of responsibilities, anything that takes the cost of changing traction away from your organisation and sticks it on the other side is something to work hard for.

 

[JohnElliott]

I've not read the article, but it's slightly worrying that someone who should have at least a basic understanding of engineering doesn't seem to appreciate that the energy density of diesel is many times that of hydrogen or LPG.

A slight update; I've rechecked the article and he was referring to American experiments with LNG.

 

[Bletchleyite]

I've not read the article, but it's slightly worrying that someone who should have at least a basic understanding of engineering doesn't seem to appreciate that the energy density of diesel is many times that of hydrogen or LPG. What works for a family car or light delivery van doesn't scale up to trains that need to accelerate several hundred tons to 125mph and back down to a stop repeatedly and continuously over the course of 16+ hours a day.

A train is also a lot bigger than a car and has more space to store such things. You've got options like slightly reducing roof height and putting it on top - if you look at a Pendolino, where the passenger compartment has about a foot on top of it for the 25kV bus line, you could easily put very substantially sized hydrogen tanks up there, and the advantage of putting them there (as on buses) is that if the tank is breached it'll very quickly be off up into the atmosphere without any harm to anyone. Indeed, it would technically make the train lighter

 

[najaB]

A train is also a lot bigger than a car and has more space to store such things.

I get that, but the energy density (as measured by Joules per litre) of diesel is ~35 MJ/l as compared to ~6MJ/l for hydrogen. So you need almost seven times more tank space for hydrogen as compared to diesel.

LNG isn't so bad, you only need about 1.5 times as much tank space as compared to diesel.

 

[Bletchleyite]

I get that, but the energy density (as measured by Joules per litre) of diesel is ~35 MJ/l as compared to ~6MJ/l for hydrogen. So you need almost seven times more tank space for hydrogen as compared to diesel.

True,but that isn't actually hard to achieve, compare the size of a DMU underfloor fuel tank with a tank taking up a similar depth (or even half the depth) over near enough the entire length of the 23m roofspace, certainly on intermediate coaches?

And then if it's bi-mode you may not need quite as much fuel on board anyway. I think the strength of this kind of thing is through running off and on wires - I can see no justification for *not* having the key mainline and commuter lines wired/third rail, but this kind of thing is perfect for stuff like Euston-North Wales Coast, Barrow/Windermere, Shrewsbury, Hull and the likes.

 

[najaB]

I think the strength of this kind of thing is through running off and on wires...

As do I. But the original question was 'Do IPEMUs mean the End of Electrification?' I think we're in agreement that the answer is 'No, but they do change the economics quite a bit'.

 

[Bletchleyite]

As do I. But the original question was 'Do IPEMUs mean the End of Electrification?' I think we're in agreement that the answer is 'No, but they do change the economics quite a bit'.

Yes, agreed.

 

[reddragon]

As do I. But the original question was 'Do IPEMUs mean the End of Electrification?' I think we're in agreement that the answer is 'No, but they do change the economics quite a bit'.

The answer is NO today, but YES in a few years!

There are capacitors in development that would allow IPEMUs to operate very successfully in a few years time. Steam only went 49 years ago, trains have a life of 30-50 years, so in that time span the new IEP Diesel engines will be replaced by batteries / capacitors.

Technology does not stand still

 

[najaB]

Technology does not stand still

That's true. However, the laws of physics aren't as mutable. There are always going to be losses incurred when using stored energy - it's just a question of how those losses balance out against losses in the transmission network.

 

[rebmcr]

Indeed, it would technically make the train lighter

No it wouldn't — it would be stored pressurised at much higher density.

 

[najaB]

No it wouldn't — it would be stored pressurised at much higher density.

*psst* I think it was a joke.