Future of SWR's class 158/159 fleet

[RobShipway]

The West of England line has a real variety of platform lengths, and with some stations only using one platform would be a good candidate to sort out and lengthen few others.

Some are full intercity length (about 900 feet or 275m)
Others nearer 800 feet (about 245m)
Others nearer 500 feet (about 150m)
It is a hangover from days of steam locos and 12-14 coach holiday trains at the junction stations, and shorter local trains at intermediate stops.



Having a mix of 4car and 6car units is obviously more complicated to diagram than identical fleet of 5car units. But I get the idea of flexibility, but a train doing a 6 hour round trip is not easy to categorise as peak or off-peak so ideal number of cars rarely suits whole route.

However the current configuration means trains from Salisbury to Waterloo are often 9x23m =207m (680feet) which on the busy peak hour main line into Waterloo wastes line capacity as others are 243m (800 feet)

Didn't SWT used to run some 10-car formations (159+159+158+158) between Salisbury and Waterloo? That's basically the same length as a double 442 or 444.

As 61653 hast stated I have previously seen at busy times 10-car formations, but at quieter times 6-car formations. Hence, the formation of dedicated 6 car units, but also having four car units as I have also seen seen SWR use two 2-car 158's coupled together on other route other than the main Exeter/Salisbury to London Waterloo. As has been stated the Romsey - Southampton route at times could do with having four coach trains.

The trains however, would be longer I suspect than two class 442 or class 444 units coupled together, as there would be a power unit within the six car and one with the 4 car. This would probably make the units more of 11.5 or 12 car length.

 

[boiledbeans2]

Didn't SWT used to run some 10-car formations (159+159+158+158) between Salisbury and Waterloo? That's basically the same length as a double 442 or 444.

Occasionally you still see that. But I'm not sure if it's diagrammed as 10-car or an ad-hoc formation.

== Doublepost prevention - post automatically merged: 26 Aug 2022 ==

There had been talk once of converting SWR's 158 & 159 units to either hybrid or full electric operation, whether this has been considered recently I am not sure.

The biggest saving by doing this would be the end of diesel on these units if they were converted to full electric operation, this in turn would give more rapid acceleration when starting from station stops and also a significant reduction in exhaust gases going into the atmosphere.

Pre-covid, there was a talk for IMechE in Portsmouth, by SWR's Neil Drury about the progress of the Class 442s.

An audience member asked if SWR had considered modifying the 159s for hybrid operation. Neil Drury replied that they did look into it, but realised it was no easy task. For example, he said that the cabin heating is powered by the engines. So if the engines are off, you have no heating. You would need to install new electric heating systems.

 

[Big Jumby 74]

But I'm not sure if it's diagrammed as 10-car or an ad-hoc formation.

SWT ran one Up morning peak as a 10 car, as specified by the 2007 refranchise. This was the 0550 Yeovil Junction to Waterloo (3-159) to Salisbury, where it attached to 4-158 + 3-159 off the depot. At Waterloo the increase in length (from 9 cars) of this service caused a fairly complex rewrite of the main line platform workings up as far as about platforms 12/13 IIRC, as the 9 car had been diagrammed in to p6, but as a 10 car had to be moved up to p7.
The formation returned west as the 0850 to Salisbury, where again a complicated three way split with associated shunts had to be undertaken.

 

[Irascible]

Occasionally you still see that. But I'm not sure if it's diagrammed as 10-car or an ad-hoc formation.

== Doublepost prevention - post automatically merged: 26 Aug 2022 ==



Pre-covid, there was a talk for IMechE in Portsmouth, by SWR's Neil Drury about the progress of the Class 442s.

An audience member asked if SWR had considered modifying the 159s for hybrid operation. Neil Drury replied that they did look into it, but realised it was no easy task. For example, he said that the cabin heating is powered by the engines. So if the engines are off, you have no heating. You would need to install new electric heating systems.

The only sane way to hybrid a 159 is to attach a separate battery unit on the end of the formation... it can pull the whole thing on the 3rd rail then, allthough youd still have to run the engines to provide heat/ac. Stick it on the Exeter end & it doesn't even take up platform space & you can detach/reattach at Salisbury just fine. That sounds a lot more risk free than trying to butcher a 30 year old underside.

( It's also a microflleet of limited use as hybrid/battery units are introduced, so don't get too excited )

 

[JonathanH]

The only sane way to hybrid a 159 is to attach a separate battery unit on the end of the formation... it can pull the whole thing on the 3rd rail then.

Electric locomotive from Basingstoke eastwards (but one of the clever things about the current use of Waterloo platforms is that 9-car 159s fit in platforms that 230m / 240m unit formations don't and a locomotive on the front will prevent that).

 

[zwk500]

Electric locomotive from Basingstoke eastwards (but one of the clever things about the current use of Waterloo platforms is that 9-car 159s fit in platforms that 230m / 240m unit formations don't and a locomotive on the front will prevent that).

Loco swaps at Basingstoke would get a colourful reaction from Ops staff and Signallers.

 

[swt_passenger]

Loco swaps at Basingstoke would get a colourful reaction from Ops staff and Signallers.

You’re not quite thinking outside the box here, surely that would happen at Oakley Parkway…

 

[boiledbeans2]

The only sane way to hybrid a 159 is to attach a separate battery unit on the end of the formation... it can pull the whole thing on the 3rd rail then, allthough youd still have to run the engines to provide heat/ac. Stick it on the Exeter end & it doesn't even take up platform space & you can detach/reattach at Salisbury just fine. That sounds a lot more risk free than trying to butcher a 30 year old underside.

( It's also a microflleet of limited use as hybrid/battery units are introduced, so don't get too excited )

They should have kept the Class 442 motor cars for this purpose. Add cabs to both ends of the motor car, and we have REP motors doing what they were designed to do.

 

[Irascible]

Electric locomotive from Basingstoke eastwards (but one of the clever things about the current use of Waterloo platforms is that 9-car 159s fit in platforms that 230m / 240m unit formations don't and a locomotive on the front will prevent that).

I was thinking you just stick it on the country end & leave it there the whole time - it can still harvest & provide power off juice - & still detach/attach London end portions at Salisbury ( although you'd have to attach another one to the bit you dropped off if you wanted that to be hybrid to somewhere too I guess - giving each unit it's own battery box would eat platform space like mad ). It did come across that you'd detach the battery box at Salisbury, my bad :P is there enough space at Waterloo platform ends to have half a vehicle off the end? that'd be a factor for MU design, not just any wierd ideas about battery tugs...

I mean, it's not the *worst* idea ever, not even original other than the harvesting part & applicable to a whole range of ageing DMUs. On the other hand not revenue earning in themselves & not exactly a large list of other applications once there's enough cash for a mass flleet replacement. Also eats budget for said fleet replacement. Would be fun to see, though.

 

[Big Jumby 74]

clever things about the current use of Waterloo platforms

OT for a second: It was always a bit of an 'art', and not everyone could get to grips with the various nuances involved. Found it helped if one could picture in ones mind the layout if looking down from above, in addition to using the graph of course. Amongst the various planning themes, Waterloo platforming was one that did challenge the grey cells at times - which was fun.

 

[zwk500]

OT for a second: It was always a bit of an 'art', and not everyone could get to grips with the various nuances involved. Found it helped if one could picture in ones mind the layout if looking down from above, in addition to using the graph of course. Amongst the various planning themes, Waterloo platforming was one that did challenge the grey cells at times - which was fun.

It's very much a Dark Art!

 

[Nicks]

I see SWR has just announced the following:

"Although there are longer-term plans to electrify some of our non-electrified routes, the implementation timetable is such that in 2030 we intend to replace the diesel fleet with an innovative self-power solution, such as battery and/or hydrogen".

 

[Mitchell Hurd]

I see SWR has just announced the following:

"Although there are longer-term plans to electrify some of our non-electrified routes, the implementation timetable is such that in 2030 we intend to replace the diesel fleet with an innovative self-power solution, such as battery and/or hydrogen".

Wow that was unexpected! Good idea though .

 

[dciuk]

I see SWR has just announced the following:

"Although there are longer-term plans to electrify some of our non-electrified routes, the implementation timetable is such that in 2030 we intend to replace the diesel fleet with an innovative self-power solution, such as battery and/or hydrogen".

Took me a while to find it, but it is on page 20 of the full report that can be downloaded from https://www.southwesternrailway.com/other/about-us/our-plan/sustainability/net-zero

Further details on page 21:

Longer-term actions – 2024 and beyond
Whilst we expect to be replacing our diesel fleet in the next five to ten years, the uncertainty
over the exact technology solution requires ongoing active and appropriate participation in
associated industry strategies, such as the TDNS and Rail Technical Strategy.

Battery fleet
The technology that replaces the diesel fleet is dependent on what becomes commercially
viable for use on the UK network. There is a level of inherent uncertainty assumed with this.
However, we are exploring several options that will reduce our emissions as part of running
our trains if implemented.
Batteries/electric trains are the most likely option for the replacement of our current fleet,
as the technology is already available, and this appears to be the most economically viable
solution. There are still some infrastructure challenges associated with this. For example,
there are economic battery limits for a journey distance (around 60-80km) which also must
factor in any energy requirements due to service delays.
This requires a more in-depth exploration into charging infrastructure, development of
charging points, gaps in the network (e.g. Basingstoke to Exeter), and any associated
emissions from this work. To address this, we have identified a need for economising on
the rolling stock installation and a lineside recharging as part of this. This could require
rapid chargers from lineside energy storage so the trains can be rapidly charged, possibly at
stations – providing modular capability.

Hydrogen fleet – a potential alternative
An alternative option to batteries is the use of hydrogen, which, depending on the production
method, has no GHG emissions associated with its direct use. At the time of writing,
hydrogen use in the UK has only just started to be commercialised in other industries.
Within rail, there are several challenges that will need to be overcome before replacement
of our fleet with hydrogen-based assets. Employing this technology could drastically reduce
our emissions from running our trains from our existing baseline and in the longer term
reduce our electricity demand.

 

[43096]

Took me a while to find it, but it is on page 20 of the full report that can be downloaded from https://www.southwesternrailway.com/other/about-us/our-plan/sustainability/net-zero

Further details on page 21:

Longer-term actions – 2024 and beyond
Whilst we expect to be replacing our diesel fleet in the next five to ten years, the uncertainty
over the exact technology solution requires ongoing active and appropriate participation in
associated industry strategies, such as the TDNS and Rail Technical Strategy.

Battery fleet
The technology that replaces the diesel fleet is dependent on what becomes commercially
viable for use on the UK network. There is a level of inherent uncertainty assumed with this.
However, we are exploring several options that will reduce our emissions as part of running
our trains if implemented.
Batteries/electric trains are the most likely option for the replacement of our current fleet,
as the technology is already available, and this appears to be the most economically viable
solution. There are still some infrastructure challenges associated with this. For example,
there are economic battery limits for a journey distance (around 60-80km) which also must
factor in any energy requirements due to service delays.
This requires a more in-depth exploration into charging infrastructure, development of
charging points, gaps in the network (e.g. Basingstoke to Exeter), and any associated
emissions from this work. To address this, we have identified a need for economising on
the rolling stock installation and a lineside recharging as part of this. This could require
rapid chargers from lineside energy storage so the trains can be rapidly charged, possibly at
stations – providing modular capability.

Hydrogen fleet – a potential alternative
An alternative option to batteries is the use of hydrogen, which, depending on the production
method, has no GHG emissions associated with its direct use. At the time of writing,
hydrogen use in the UK has only just started to be commercialised in other industries.
Within rail, there are several challenges that will need to be overcome before replacement
of our fleet with hydrogen-based assets. Employing this technology could drastically reduce
our emissions from running our trains from our existing baseline and in the longer term
reduce our electricity demand.

I'm afraid it's all just meaningless PR speak. SWR are in no position to say anything about replacing their 15x fleet with whatever form of bionic duckweed is in vogue this month: their contract ends well before 2030 and in any case, DfT controls the railway so has final say on any such plans.

 

[Trainbike46]

Took me a while to find it, but it is on page 20 of the full report that can be downloaded from https://www.southwesternrailway.com/other/about-us/our-plan/sustainability/net-zero

Further details on page 21:

Longer-term actions – 2024 and beyond
Whilst we expect to be replacing our diesel fleet in the next five to ten years, the uncertainty
over the exact technology solution requires ongoing active and appropriate participation in
associated industry strategies, such as the TDNS and Rail Technical Strategy.

Battery fleet
The technology that replaces the diesel fleet is dependent on what becomes commercially
viable for use on the UK network. There is a level of inherent uncertainty assumed with this.
However, we are exploring several options that will reduce our emissions as part of running
our trains if implemented.
Batteries/electric trains are the most likely option for the replacement of our current fleet,
as the technology is already available, and this appears to be the most economically viable
solution. There are still some infrastructure challenges associated with this. For example,
there are economic battery limits for a journey distance (around 60-80km) which also must
factor in any energy requirements due to service delays.
This requires a more in-depth exploration into charging infrastructure, development of
charging points, gaps in the network (e.g. Basingstoke to Exeter), and any associated
emissions from this work. To address this, we have identified a need for economising on
the rolling stock installation and a lineside recharging as part of this. This could require
rapid chargers from lineside energy storage so the trains can be rapidly charged, possibly at
stations – providing modular capability.

Hydrogen fleet – a potential alternative
An alternative option to batteries is the use of hydrogen, which, depending on the production
method, has no GHG emissions associated with its direct use. At the time of writing,
hydrogen use in the UK has only just started to be commercialised in other industries.
Within rail, there are several challenges that will need to be overcome before replacement
of our fleet with hydrogen-based assets. Employing this technology could drastically reduce
our emissions from running our trains from our existing baseline and in the longer term
reduce our electricity demand.

I see the logic in battery trains to replace the 158/159 fleet - but how do they believe hydrogen could reduce electricity demand when hydrogen produced from electricity is a very inefficient process? Are they just ignoring the electricity use from producing hydrogen?

Please tell me they're not suggesting replacing 3rd rail electric trains with hydrogen trains?

 

[RobShipway]

I see the logic in battery trains to replace the 158/159 fleet - but how do they believe hydrogen could reduce electricity demand when hydrogen produced from electricity is a very inefficient process? Are they just ignoring the electricity use from producing hydrogen?

Please tell me they're not suggesting replacing 3rd rail electric trains with hydrogen trains?

Could you not have a train that works on third rail, but could change to either battery or hydrogen power? If you can, then why would they be considering replacing 3rd rail electric trains with hydrogen trains?

The obvious replacement for 3rd rail, is to replace it with 25Kv AC overhead I would have thought rather either battery or hydrogen trains over the 3rd rail sections. However, until there is a government in the UK that is willing to provide the finance for all rail routes to be replaced with 25KV AC overhead, that are either 3rd rail or run with diesel hauled trains currently, then other answers to stop CO2 need to be considered before 2050.

 

[LOL The Irony]

I'm afraid it's all just meaningless PR speak. SWR are in no position to say anything about replacing their 15x fleet with whatever form of bionic duckweed is in vogue this month: their contract ends well before 2030 and in any case, DfT controls the railway so has final say on any such plans.

It's good to be looking to the future, as franchises/contracts in a similar position with aged rolling stock have been doing. Plus, doesn't everything get tupe'd over in a new franchise anyways? Also, just because the government don't want to spend money now (well at least on anything that isn't bankers, energy companies and the 1%), doesn't mean that they won't be in a position to then.

 

[zwk500]

I see the logic in battery trains to replace the 158/159 fleet - but how do they believe hydrogen could reduce electricity demand when hydrogen produced from electricity is a very inefficient process? Are they just ignoring the electricity use from producing hydrogen?

Bulk production of hydrogen can allow more efficient processes, although then you have issues of transporting and storing it. There's also other ways of producing hydrogen without using as much electricity (although there are other problems with these methods). There's a hell of a lot of untested theory and misinformation out there about hydrogen production, and sifting out what is practicable theory, what is unpracticable theory, and what is rubbish is not easy for bystanders like me!

Please tell me they're not suggesting replacing 3rd rail electric trains with hydrogen trains?

They won't be. They would only replace the diesel fleet with hydrogen trains.

Could you not have a train that works on third rail, but could change to either battery or hydrogen power?

Yes, battery is obvious, hydrogen would depend on exact configuration but definitely possible.

The obvious replacement for 3rd rail, is to replace it with 25Kv AC overhead I would have thought rather either battery or hydrogen trains over the 3rd rail sections. However, until there is a government in the UK that is willing to provide the finance for all rail routes to be replaced with 25KV AC overhead, that are either 3rd rail or run with diesel hauled trains currently, then other answers to stop CO2 need to be considered before 2050.

I can't see the expenditure for replacing one form of electrification with another being politically conscionable while there are unelectrified lines still outstanding. Hydrogen should (but won't) be considered a stop gap to electrify the bulk of the network, with every EMU eventually fitted with a c.50-80km battery range to permit the maximum usage of wired routes. Conversion of 3rd rail will require 3 requirements: 1. The viable OLE network to be 100% complete 2. All signalling on the 3rd rail area to be immunised (or otherwise not impacted) 3. Units capable of bridging unelectrified gaps as the conversion gets underway.

 

[Domh245]

I see the logic in battery trains to replace the 158/159 fleet - but how do they believe hydrogen could reduce electricity demand when hydrogen produced from electricity is a very inefficient process? Are they just ignoring the electricity use from producing hydrogen?

Please tell me they're not suggesting replacing 3rd rail electric trains with hydrogen trains?

They're drawing the boundary at the rolling stock and not concerning themselves about how they get their energy (which is cheeky but rather standard practice). The fact that buying 1MWh's worth of Hydrogen has 2MWhs electricity consumption behind it doesn't matter to them.

Very simply, their logic is that both hydrogen and battery trains takes in electricity when running above the third rail, but the Hydrogen unit will consume less electricity than a Battery EMU as it isn't needing to recharge the batteries from external energy source (noting that a Hydrogen MU will be a battery EMU with reduced batteries, plus hulking great storage vessels & fuel cells)

I'm afraid it's all just meaningless PR speak. SWR are in no position to say anything about replacing their 15x fleet with whatever form of bionic duckweed is in vogue this month: their contract ends well before 2030 and in any case, DfT controls the railway so has final say on any such plans.

Beyond what @LOL The Irony has said about this work (and employees who produced it) carrying forward into future iterations of 'South Western Franchisee ltd', there are specific items in their ERMA which this report would appear to be the answer to, eg:

10.1 (a) (iv) an annual improvement plan providing:
(A) details of any new technologies, processes, developments and/or proposals which could improve the provision of the Franchise Services, reduce the cost of providing the Franchise Services or enable the Franchise Services to be provided more efficiently;
(B) an analysis of the impact of any technologies, processes, developments and/or proposals that are proposed in relation to the Franchise Services, including analyses of the costs of and timescale for effecting such changes and the impact on the provision of the Franchise Services;
(C) details of those technologies, processes, developments and/or proposals which the Franchisee proposes to implement during that Franchisee Year; and
(D) an analysis of the technologies, processes, developments and/or proposals which the Franchisee implemented in the previous Franchisee Year, including details of any cost reductions and/or efficiency gains arising from the same and a reconciliation to the annual improvement plan for the previous Franchisee Year;
..
15.3 (c) The Franchisee shall for the purposes of monitoring and reducing emissions from traction:
(i) through an RSSB-led industry working group, support the development and delivery of a policy in relation to the maximum time for which a train's engine may be kept idling while stationary;
(ii) use all reasonable endeavours to work with the fleet owner to develop an emissions reduction pathway for all diesel rolling stock vehicles;
(iii) consider cost-effective opportunities to reduce emissions through operational or maintenance changes and, where reasonable and with the agreement or direction of the Secretary of State, make changes to rolling stock vehicles to reduce their air pollution impact;
(iv) provide to the Secretary of State, RSSB or any person whom the Secretary of State might reasonably specify free-of-charge access to rolling stock vehicles and infrastructure for emissions testing as requested by the Secretary of State from time to time; and
(v) provide to the Secretary of State such information and/or data in relation to exhaust emissions from rolling stock vehicles comprised within the Train Fleet as the Secretary of State may reasonably require from time to time for the purposes of data collection and analysing the consequent impact of such emissions on air quality in Depots and Stations and along the Routes on which such rolling stock vehicles are deployed.
(d) The Franchisee shall for the purposes of supporting wider industry approaches to emissions reduction:
(i) consider the impact of any rolling stock vehicle, operational or infrastructure changes on emissions; and
(ii) provide to the Secretary of State and RSSB a named contact as a point of enquiry in relation to air quality.

Also a few references to "Sustainable Development Strategy" which I can't find more specifics about, but would again imply that this is certainly not out of character

 

[dciuk]

Batteries/electric trains are the most likely option for the replacement of our current fleet,
as the technology is already available, and this appears to be the most economically viable
solution. There are still some infrastructure challenges associated with this. For example,
there are economic battery limits for a journey distance (around 60-80km) which also must
factor in any energy requirements due to service delays.
This requires a more in-depth exploration into charging infrastructure, development of
charging points, gaps in the network (e.g. Basingstoke to Exeter), and any associated
emissions from this work. To address this, we have identified a need for economising on
the rolling stock installation and a lineside recharging as part of this. This could require
rapid chargers from lineside energy storage so the trains can be rapidly charged, possibly at
stations – providing modular capability.

Based on the above, presumably a battery/electric hybrid would use 3rd rail for charging between Basingstoke and Waterloo, but is adding additional 3rd rail at selected locations between Basingstoke and Exeter an acceptable option or would it need to be overhead electrification or wireless charging. Would Rapid charging at stations for the approx 1 minute they are stopped be sufficient to power a train all the way to Exeter and back? Perhaps if was to be extended about a mile or so outside of the station to allow trains to run off electric while accelerating away from the platform that might help

 

[MattRat]

I see the logic in battery trains to replace the 158/159 fleet - but how do they believe hydrogen could reduce electricity demand when hydrogen produced from electricity is a very inefficient process? Are they just ignoring the electricity use from producing hydrogen?

Please tell me they're not suggesting replacing 3rd rail electric trains with hydrogen trains?

Batteries can't really store much electricity in a compact manner, so you can't just have battery storage to charge batteries from, especially if you have to charge halfway through a journey. Not only can hydrogen go further between fillups, they are developing ways to store a lot of hydrogen in a compact manner with things like metal hydrides.

So, while generating hydrogen takes more electricity, you can generate it whenever it's feasible, then just store it for later use (hopefully). Sort of like those giant coal storage areas in the age of steam, able to just sit around until needed.

 

[Towers]

Excellent to hear that one of the vanishingly few remaining decent train fleets is hopefully to be with us until the end of the decade.

Let's hope they don't ruin the interiors in the meantime!

That is all!

 

[zwk500]

Based on the above, presumably a battery/electric hybrid would use 3rd rail for charging between Basingstoke and Waterloo, but is adding additional 3rd rail at selected locations between Basingstoke and Exeter an acceptable option or would it need to be overhead electrification or wireless charging.

Additional 3rd rail for long enough to make a meaningful charge is unlikely to be approved.

Would Rapid charging at stations for the approx 1 minute they are stopped be sufficient to power a train all the way to Exeter and back?

Probably not, unless they have VERY efficient regenerative charging when going downhill. 2/3 minute stops however might be more feasible, depending on the turnround at Exeter.

Perhaps if was to be extended about a mile or so outside of the station to allow trains to run off electric while accelerating away from the platform that might help

3rd rail is unlikely to be installed anywere around Exeter. It may be extended slightly beyond Worting Jn towards Andover but only about a mile or so.

 

[Irascible]

3rd rail is unlikely to be installed anywere around Exeter. It may be extended slightly beyond Worting Jn towards Andover but only about a mile or so.

Might get away with the odd length of wires in a couple of the turnaround/stabling sidings - the stock would be usable for Barnstaple too, if it can get from Salisbury up & down all those hills.

 

[zwk500]

Might get away with the odd length of wires in a couple of the turnaround/stabling sidings - the stock would be usable for Barnstaple too, if it can get from Salisbury up & down all those hills.

OLE maybe, 3rd rail very unlikely.

 

[dciuk]

Might get away with the odd length of wires in a couple of the turnaround/stabling sidings - the stock would be usable for Barnstaple too, if it can get from Salisbury up & down all those hills.

Although SWR do not serve Barnstaple and while similar units are (sometimes) currently used on the Barnstaple branch, if new units are being considered, GWR services from Barnstaple to Exeter with a journey time of just over an hour my not require the same type of rolling stock as over three and a half hour end to end journeys on the Waterloo to Exeter service

 

[Xavi]

Additional 3rd rail for long enough to make a meaningful charge is unlikely to be approved.

Why? NR and ORR are considering reversing previous policy and allowing extensions of 3rd rail.

 

[Trainbike46]

Why? NR and ORR are considering reversing previous policy and allowing extensions of 3rd rail.

Extension fully in 3rd rail land may happen (though I still think it's unlikely), such as for electrifying the remaining Southern diesel services. However, building 3rd rail in Exeter seems so unlikely as to be impossible

 

[61653 HTAFC]

Why? NR and ORR are considering reversing previous policy and allowing extensions of 3rd rail.

If we didn't already have 3rd rail covering fairly long distances, there's no way we'd choose to do so now. No other countries use it on the scales and at the speeds we do, and that's the case for a good reason.

That said, 3rd rail all the way to Exeter would still be a better solution than either hydrogen or batteries.