With battery technology rapidly advancing, how much OHLE do we actually need to achieve decarbonisation ASAP?

[PTR 444]

If we are to achieve decarbonisation on the railway by 2040, we are going to need a fully electrified network. In the old days, this would have meant 100% OHLE or third rail coverage, but now with battery technology advancing, it is becoming ever more possible to achieve full electrification without even wiring many routes.

Let’s say all the main passenger and freight lines are fully wired, so complete the GWML to Swansea, MML to Sheffield/Moorthorpe, Transpennine Routes, Chiltern/Snow Hill Lines, Cross Country Routes and Birmingham to Felixstowe. With that all done, you have a trunk network of OHLE which battery trains can recharge on, and assuming these have a range of 100 miles on battery power, you could go quite a long way off the wires, eliminating the need to install costly OHLE in many places to begin with.

Even so, this shouldn’t be an excuse for not eventually completing the wires. This is simply a stop gap stage to achieve decarbonisation with minimal infrastructure investment. After this has happened, then expansion to the OHLE network can be looked into to improve efficiency.

Assuming all the main lines listed above are fully wired and battery EMUs by then have a range of 100+ miles, what’s the minimum amount of additional OHLE that would be required to achieve decarbonisation at the earliest possible date?

 

[Randomer]

I think it would be possible but you would need quite a lot more partial electrification for charging on the move. Or it is going to require further development of rapid charging if you aren't going to build much more OLE. Using the FLIRT Akku as an example of something that should be possible on the UK loading gauge you are looking at about 150km range. You could probably extend this with a power pack battery module similar to the ones being fitted to the TFW Class 756. The Japanese units that have longer ranges wouldn't fit into our loading gauge without serious redesign.

Assuming that operationally you aren't prepared to have battery units routinely running to less than 25% charge, which with longer term battery degradation could start to become a problem, then realistically you need some kind of charging solution every 125km of distance. It would also have to be some form of rapid charging unless you extend the OLE far enough in these areas for slower charging on the move.

Thinking about the south west as an example:
- Around Exeter for the South Devon metro units and whatever replaces the SWR West of England services (Basingstoke to Exeter is about 150km.)
- Some solution for charging at Penzance and Long Rock depot, probably requiring rapid charging if you intend to keep the Class 800's converted to battery in place of GU. It is about 100km Plymouth to Penzance so you would need something to make this work as a round trip.
- Also something around Plymouth to services that are going to carry on to Penzance.

I genuinely think by the time that all this has been sorted and all the rolling stock modified or replaced that just biting the bullet and doing full electrification might actually be quicker.

 

[eldomtom2]

It's unclear, and it's worth keeping in mind freight as well, since that's less suitable for battery operation. The sensible thing to do would be to base plans on battery technology as it is now, to avoid the possibility of technology not advancing as quickly as hoped.

 

[Snow1964]

Realistically don't want gaps much further than 50 miles, I know on favourable days might get nearer 70 miles, but in depths of winter or in a heatwave when there is disruption and delays don't want to be struggling to maintain carriage temperatures

For branch lines, when go out and back, that is effectively 25 miles each way. How much time under the wire is going to limit charging, although could have plug in fast charging.

Not convinced about the plug in route, it was tried a termini like Paddington and Kings Cross with HSTs, but became disused because it was felt it was too much of a faff unless train was going to sit in platform for ages.

I don't think unelectrified gaps would work on main lines or secondary lines carrying lots of freight. A few metres of dead or neutral section is ok on battery, but idea of something like electrically running a 4000t stone train on the wires from Frome to Westbury, then hoping battery can get it to Newbury maintaining 60mph is just laughable.

 

[D365]

Batteries are never going to supplant OHLE.

 

[zwk500]

Batteries are going to be useful for little infill islands or for extensions of branches where traffic dropping off makes OLE unviable. I'd still expect to need OLE on the majority of the network though if you wanted zero-carbon.

 

[Bill57p9]

What are the potential solutions for long remote routes, such as West Highland, Far North, Stranraer, Heart of Wales?

Whilst I am fully aware that the Scot Gov strategy has spoken of "alternative fuels", with the current technology trajectory do we think BEMU might become a realistic option?
The FNL & WHL passing loops all have powered TPWS and given the quantity of wind generation there the power grids are better than might be imagined, therefore could a Vivarail style flash charging solution be practical in that environment?

 

[Snow1964]

What are the potential solutions for long remote routes, such as West Highland, Far North, Stranraer, Heart of Wales?

Whilst I am fully aware that the Scot Gov strategy has spoken of "alternative fuels", with the current technology trajectory do we think BEMU might become a realistic option?
The FNL & WHL passing loops all have powered TPWS and given the quantity of wind generation there the power grids are better than might be imagined, therefore could a Vivarail style flash charging solution be practical in that environment?

The simple answer is unlikely to be tackled for 20+ years, not before mid 2040s. By then might be some new technology available at reasonable cost.

In meantime there are plenty of DMUs built within last decade which will possibly find way onto these lines

 

[PTR 444]

Batteries are going to be useful for little infill islands or for extensions of branches where traffic dropping off makes OLE unviable. I'd still expect to need OLE on the majority of the network though if you wanted zero-carbon.

I think they will also be useful for inter-regional routes which already have several discontinuous electrified sections. Liverpool - Norwich, Cardiff - Portsmouth etc.

 

[zwk500]

I think they will also be useful for inter-regional routes which already have several discontinuous electrified sections. Liverpool - Norwich, Cardiff - Portsmouth etc.

Yes, those are good examples of the infill islands.

 

[dosxuk]

Batteries swap one environmental problem for another. They're only friendly in terms of their reduction in carbon emissions at the point of usage. They have long term financial and environmental issues, so even if we ignore the environmental cost of battery manufacture, OHLE will still be a better solution.

We need to stop thinking of batteries as an alternative to full electrification, just as we have finally cottoned on to bi-modes not being an alternative. Both should be seen as supplementary options for very small, occasional and unusual uses, not an excuse to stop installing wires.

 

[Stewart2887]

The number of hybrid electric bus fires i've seen round here gives me concerns. Trains will be even more risky

 

[Turtle]

Batteries swap one environmental problem for another. They're only friendly in terms of their reduction in carbon emissions at the point of usage. They have long term financial and environmental issues, so even if we ignore the environmental cost of battery manufacture, OHLE will still be a better solution.

We need to stop thinking of batteries as an alternative to full electrification, just as we have finally cottoned on to bi-modes not being an alternative. Both should be seen as supplementary options for very small, occasional and unusual uses, not an excuse to stop installing wires.

As you say, yet another good argument for full electrification or, as we should just say, electrification, electrification, electrification.

 

[Sorcerer]

This might end up being worthy of it's own discussion, but I genuinely think that too much faith is being put in battery technology. It might have it's place as a stop gap or backup, but the end goal should really be electrification. If the idea is to charge them under the wires before the trains themselves go down a non-electrified route, then why not just electrify the route itself? Not only have you saved money in the long-term by making sure future rolling stock does not require batteries, but you also save on maintenance costs. Again, it's not that batteries are totally useless, but they are not an alternative to electrification and shouldn't be treated as such.

 

[renegademaster]

This might end up being worthy of it's own discussion, but I genuinely think that too much faith is being put in battery technology. It might have it's place as a stop gap or backup, but the end goal should really be electrification. If the idea is to charge them under the wires before the trains themselves go down a non-electrified route, then why not just electrify the route itself? Not only have you saved money in the long-term by making sure future rolling stock does not require batteries, but you also save on maintenance costs. Again, it's not that batteries are totally useless, but they are not an alternative to electrification and shouldn't be treated as such.

It's starting to sound awfully like all the hype that was around hydrogen. Quite expensive, a sticking plaster , and seen more in the promotional magazines of rolling stock manufactures than out on the track. The biggest adopter of them, Japan ,only has 23 across the whole country.

 

[HSTEd]

Fundamentally the railway industry is incapable of delivering electrification at reasonable cost at the present time, just as it is incapable of providing the required resignalling or any other infrastructure project at reasonable cost.

Network Rail third rail is out without massive changes to working practices (to bring them in line with London Underground), 25kV is ruinously expensive and there are precious few other options.

Batteries or diesel, I chose batteries every time.

 

[renegademaster]

Az

Fundamentally the railway industry is incapable of delivering electrification at reasonable cost at the present time, just as it is incapable of providing the required resignalling or any other infrastructure project at reasonable cost.

Network Rail third rail is out without massive changes to working practices (to bring them in line with London Underground), 25kV is ruinously expensive and there are precious few other options.

Batteries or diesel, I chose batteries every time.

The Diesels in the south are such a drop in the ocean of overall Carbon emissions and pretty low per capita considering the numbers on them, I'd rather they just continue and the money get used to pay staff better so more sign up and the service reliability issues ease. Better a diesel train than no train

 

[HSTEd]

The Diesels in the south are such a drop in the ocean of overall Carbon emissions and pretty low per capita considering the numbers on them, I'd rather they just continue and the money get used to pay staff better so more sign up and the service reliability issues ease. Better a diesel train than no train

Half a million tonnes of fuel oil is used by the railway each year.

That might appear to be a drop in the ocean now, but it will not be when electric vehicles drive road emissions into the ground.
Once the railway is stripped of its environmentalist credentials a "diesel train" may not be seen as better than no train.

Trying to divert capital spending to prop up day to day pay bills is a quick way to drive the railway even further into the ground......