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Suggestion: Conversion of former Southern Region DC to AC

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adrock1976

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What's it called? It's called Cumbernauld
Unsure if there are any similar old threads regarding this topic.

As it has been publicly known the proposals for the will it, won't it go ahead Electric Spine project, I have thought about converting the whole of the former Southern Region from DC to AC. This assumes that Southampton - Basingstoke (both routes via Eastleigh and Laverstock Junction) - Reading - Oxford - Bletchley - Bedford Midland and Midland Railway metals northwards have already been committed and teams mobilised for that project. I have outlined the details for each of the 3 Southern Region companies below.

London & South Western Railway


1)
Continue the conversion westwards from Southampton Central to Weymouth. I believe that most of this section was third rail electrified in 1988, which tied in with the introduction of the most discussed class of traction on this forum. The third rail equipment could then be used as spares for the Isle of Wight.

2)
Continue the conversion eastbound from both Southampton and Eastleigh to Portsmouth Harbour, also eastbound from Basingstoke to Woking, plus the fast lines to London Waterloo. Furthermore, convert the Portsmouth Direct route via Haslemere, and the Guildford New Line via Cobham & Stoke d'Abernon to AC. Perhaps a new AC only class of trains could be built for these routes, and be given the designation of Class 542?

3)
Convert the line from Pirbright Junction to Alton, plus the spur from Aldershot to Guildford, and Ash Vale to Ascot. These routes to be operated by something similar to the Class 542s (perhaps Class 543s?) that are suited to this medium distance/local routes.

4)
Have a separate team to continue the wires west of Laverstock Junction to Barnstaple, Exmouth, the Yeovil curve, and maybe to Okehampton/Plymouth via Tavistock. The routes beyond Exeter could be done in partnership with the GWR team if wires ever reach that far along GWR metals. The present Waterloo - Exeter to be operated by Class 542s.

The present day Class 450s (I believe there are 127 of them) can be transferred to the local all stations stopping services that operate within and just beyond the London Zones, meaning that the Class 455s (I believe that they were built in 1982) can be retired. This may or may not determine what stock will be used if TfL ever takes over responsibility for the local London services, and what form the Chelsea - Hackney project will look like when it is constructed. The Inner London local services to be converted to AC when the Class 450s are due for retirement.

London, Brighton, and South Coast Railway

1)
I'll start here with what I perceive to be the blindingly obvious: Continue the wires from City Thameslink all the way to Brighton via both the Quarry route and via Redhill. Also the fast lines from London Victoria to East Croydon as well, and the branches to Tattenham Corner and Caterham too. This would be one less thing to go wrong in the core as the train would no longer have to switch between different voltage systems.

2)
Convert Three Bridges - Littlehampton and Bognor Regis via Horsham to AC, and Keymer Junction - Seaford to AC as well. Then Brighton - Eastbourne and Hastings (also reinstating the top side of the triangle north of Hampden Park Sussex), and Brighton - Havant. The Class 313s can be retired, as they are used on the local all stations services east and west of Brighton. New class of trains for the limited stop services to/from Victoria and London Bridge, perhaps Class 552s?

The Class 377s could then be transferred to the local all stations services within and just outside London, so as to retire the Class 455s. Inner London local services to be converted to AC when the Class 377s are due to be retired.


South Eastern Railway/London, Chatham, & Dover Railway


1)
Convert Ashford – Ramsgate via Canterbury West, Dover Priory – Margate – Faversham – Swanley, and Swanley – Ashford via Maidstone to AC. Also the line to Sheerness-on-Sea to be converted as well. This would allow the Class 395s to run solely on AC.


2)
Convert the fast lines out of Charing Cross and Cannon Street to AC via the SER mainline to Hastings and Tonbridge – Dover Priory. Electrify Hastings – Ashford (Kent), and convert Ashford – Chislehurst Junction too. A new class of trains to be introduced for the limited stop services, perhaps designated Class 562s?


3)
Convert Chislehurst Junction – London Victoria fast lines to AC, Tonbridge – Strood, Sevenoaks – Otford, Shortlands – Blackfriars, and East Croydon – East Grinstead and Uckfield/Lewes.


4)
Fill in the missing gaps of the Reading, Guildford, & Reigate Railway using AC. Dual voltage Class 377s could be used initially before the DC sections are converted to AC. Perhaps the conversion could be done in conjunction with the Waterloo – Reading/Windsor & Eton Riverside project when that is due to be converted?


5)
The final route outside of London to be converted to AC would be the Redhill – Tonbridge section, as I believe that was upgraded in the early 1990s for Eurostar. The dismantled DC equipment could then be reused on the Isle of Wight as spares.


On a final point, I have deliberately not made many references to converting local all stations services that operate within or just outside the London fare zones, as it has been mentioned in earlier threads that TfL would like to be responsible for those services. Also, forgive me if my suggestions may not be entirely clear, as it is not often I venture south of the mighty Thames. As the conversion from DC to AC is a complex project, I believe it is better to build on from the proposed Electric Spine project (if it ever gets off the ground). Regarding engineering staff to do the work, I would suggest the simple method of how British Rail proposed in their 1980 AC electrification report for routes north of the Thames by having 4 teams on the ground. 2 routes slit into 2 teams, with one starting at each end and meeting in the middle.
 
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steamybrian

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How much would it cost...?
Most bridges and tunnels would have to be rebuilt.
The South Eastern Railway originally built the railway in the 1800s to very tight clearances.
 

Deepgreen

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How much would it cost...?
Most bridges and tunnels would have to be rebuilt.
The South Eastern Railway originally built the railway in the 1800s to very tight clearances.

It'll have to be done at some point...unless a new fuel regime is produced that renders electrification redundant, e.g. such concepts as fuel cells, hydrogen power and so on, that may come on stream and provide cheap, reliable, eco-friendly and powerful enough output. A few decades might well see something that eliminates the need for wires everywhere.
 

Clip

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How much would it cost...?
Most bridges and tunnels would have to be rebuilt.
The South Eastern Railway originally built the railway in the 1800s to very tight clearances.

No need to raise them just drop the track as they have done in other places.
 

aylesbury

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This has been discussed for the so called Electric Spine Southampton to Oxford and northwards.But the project has stalled on cost grounds and wether or not it will actually be worthwhile now that the class 88 is on the horizon.As to converting the rest of the southern to overhead wires I cant see the will or money being there to do it.
 

swt_passenger

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It would realistically have to be done from the outside of the network inwards towards major junctions. Hence all stock used on wider electrifications such as to Weymouth or to Exeter via Salisbury would have to be dual voltage to run into Waterloo.

I suggest the likely timescales required mean it would be pointless worrying about allocation of current stock such as 450s, it would be approaching retirement before there was nowhere left to run it on DC, given it could be re-allocated anywhere on the DC network as other older stock (e.g. ex BR) is phased out Alternatively it's far more likely they'd progressively convert significant numbers of 450s and 444s into dual voltage for electric spine purposes anyway.

It is not at all straightforward to suggest that TfL operated routes could be separated for the purposes of electrification policy, transfers to TfL cannot be done on a line by line basis, everyone will still be sharing the same track layouts, there are far too many flat junctions and crossings to separate into AC and DC.

BTW, and as an aside, I fail to see the logic of suggesting Class 542 for an AC EMU. 5XX series is still allocated to DC only, new AC or dual voltage will more likely be in the 300 or 700 ranges.
 
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NotATrainspott

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It'll have to be done at some point...unless a new fuel regime is produced that renders electrification redundant, e.g. such concepts as fuel cells, hydrogen power and so on, that may come on stream and provide cheap, reliable, eco-friendly and powerful enough output. A few decades might well see something that eliminates the need for wires everywhere.

Hydrogen is a horrendously inefficient energy storage medium. The inefficiency of fossil fuels can be tolerated because we don't need to produce the fuel in the first place, but for every 100 joules of energy we put in to producing hydrogen, by the end of it you only get 30 joules back out at the other end. AC OHLE, on the other hand, would give you something like 90 joules for the same input. There is no more efficient way to power a train.
 

61653 HTAFC

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Hydrogen is a horrendously inefficient energy storage medium. The inefficiency of fossil fuels can be tolerated because we don't need to produce the fuel in the first place, but for every 100 joules of energy we put in to producing hydrogen, by the end of it you only get 30 joules back out at the other end. AC OHLE, on the other hand, would give you something like 90 joules for the same input. There is no more efficient way to power a train YET.

Fixed that for you. ;)
 

najaB

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Hydrogen is a horrendously inefficient energy storage medium.
True, but it depends on where the input energy is coming from. If it's 'free' energy (solar, wind) then you can tolerate inefficiency a lot more than if you're 'paying' for the energy (gas, oil).

That said, there's a lot of interesting work in the area of bio-chemical solar hydrogen production (basically copying the first stage of photosynthesis) which has the potential to be quite efficient.
 

edwin_m

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Hydrogen is also far less dense than longer-chain hydrocarbons such as diesel fuel, and being a gas needs more complicated storage. So it costs and weighs more than diesel for a shorter range. I believe also fuel cells aren't ideal for the sort of variable power demand presented by trains, so might need to run in hybrid mode with batteries. Unless this technology improves significantly it's not viable for trains except perhaps for slow and quiet rural routes which aren't relevant here.

The RSSB report on DC to AC conversion (which is hidden behind a login but I think anyone can apply for one) also favoured the "outside in" approach, for three main reasons if I recall correctly:
- Most of the longer-distance trains on the DC network are designed for possible AC conversion. Most inner-suburban ones aren't so better to wait until these are withdrawn.
- The signalling on the outer parts of the network uses fairly new equipment, much of which is AC compatible. The older signalling closer to London would cost a huge amount to immunise against AC interference, so again better to wait until that is replaced.
- The further away from London, the further apart the trains and stations are and the more difficult it is to find power supplies for substations. All these factors tilt the cost balance towards AC.

Having said all that I don't think the case is yet made on economic grounds but it should certainly be considered when major renewals of the DC equipment become due. The increased safety of the AC system (being discussed on another thread) may help to make the case too.
 
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JamesRowden

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Hydrogen is also far less dense than longer-chain hydrocarbons such as diesel fuel, and being a gas needs more complicated storage. So it costs and weighs more than diesel for a shorter range. I believe also fuel cells aren't ideal for the sort of variable power demand presented by trains, so might need to run in hybrid mode with batteries. Unless this technology improves significantly it's not viable for trains except perhaps for slow and quiet rural routes which aren't relevant here.

The RSSB report on DC to AC conversion (which is hidden behind a login but I think anyone can apply for one) also favoured the "outside in" approach, for three main reasons if I recall correctly:
- Most of the longer-distance trains on the DC network are designed for possible AC conversion. Most inner-suburban ones aren't so better to wait until these are withdrawn.
- The signalling on the outer parts of the network uses fairly new equipment, much of which is AC compatible. The older signalling closer to London would cost a huge amount to immunise against AC interference, so again better to wait until that is replaced.
- The further away from London, the further apart the trains and stations are and the more difficult it is to find power supplies for substations. All these factors tilt the cost balance towards AC.

Hydrogen fuel has more than three times the energy density of petrol.
 

NotATrainspott

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Fixed that for you. ;)

I strongly disagree. 25kV AC is the optimum voltage for railway applications and a direct supply of electricity from source to train will always beat any alternative. The amount of energy used by the railway is so enormous that the upfront energy cost of installing OHLE and the assorted other components of the traction supply is dwarfed.
 

najaB

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BMW were happy with that in their Hydrogen powered racing car of the previous decade.
The explosive potential of a tank large enough to power a race car for c. 300km is significantly less than that of a tank large enough to power a train for four or five times that distance.
 

JamesRowden

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The explosive potential of a tank large enough to power a race car for c. 300km is significantly less than that of a tank large enough to power a train for four or five times that distance.

The amount of explosive energy contained within the fuel of a hydrogen train is independent of the pressure that the fuel is stored at (for a given mass of fuel). Therefore it is the highly explosive nature of hydrogen rather than a lack of energy density which is one of the issues with the idea of hydrogen powered trains.
 
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najaB

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Compared with the energy required to power a train for a day?
No. But an uncontrolled rupture of a diesel tank in an accident is going to be a lot less disruptive to anyone nearby than the uncontrolled rupture of an equivalent large tank of high-pressure gas.

Think this, but five or six times larger:
[youtube]jOf69xHnyrk[/youtube]
Full story here.
 
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swt_passenger

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I bet the OP didn't expect that after a few hours the majority of replies would be about the pros and cons of hydrogen...
 

416GSi

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Because it is incredibly inefficient.

Yes, it's cheaper to install, but whole life running costs are greater.

True....but with many miles of un-electrified lines, why would you want to convert lines which are already electrified?

In my opinion It would be better to finish electrifying the rest of the country non electric lines first.
 

edwin_m

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PV equals nRT

It's a long time since I did any physical chemistry and I don't know what that one means, but if you're saying a litre of hydrogen at atmospheric pressure has more energy than a litre of petrol then I don't believe you. As soon as you have to compress it then the extra weight of the pressure vessel needs to be accounted for.
 

AM9

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It's a long time since I did any physical chemistry and I don't know what that one means, but if you're saying a litre of hydrogen at atmospheric pressure has more energy than a litre of petrol then I don't believe you. As soon as you have to compress it then the extra weight of the pressure vessel needs to be accounted for.

... and the energy needed to compress/cool the hydrogen which is low density gas at ambient temperature & pressure, into liquid.
--- old post above --- --- new post below ---
Absolutely unless a bit becomes life expired before then.

... and as many of the lines currently with 3rd rail DC were originally electrified because of their heavy traffic, that heavy traffic to this day requires the DC equipment's, frequent, (and in many cases imminent) replacement. The sooner the bullet is bitten and conversion to current best electrification practice is undertaken, the quicker the energy and maintenance benefits will be realised. This will ultimately free financial and engineering resources to spread the benefits of OLE to non-electrified routes.
 

Julia

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BMW were happy with that in their Hydrogen powered racing car of the previous decade.

True, but then racing drivers tend to accept crashing and burning (literally) as an occupational hazard. Can't see commuters being enamoured of fireproof suits and helmets as mandatory daily attire.
 

The Ham

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How much would it cost...?
Most bridges and tunnels would have to be rebuilt.
The South Eastern Railway originally built the railway in the 1800s to very tight clearances.

Following the work done on the line south of Basingstoke to take containers, it has shown that lowering the track could be an option if the topography, water table and drainage systems allowed. That could then save having to rebuild quite a few tunnels (although not all of them).

It is also worth noting that every time a new bridge with lifts is put in at the stations they are built to allow electrification. Add to that those bridges which would already be high enough anyway (as pointed out some are built with closer tolerances than others) and the number of bridges that need to be rebuilt may not be as significant as it could appear from first glance.

Even those that do need to be rebuilt could provide benefits to the local community (better footway provision, removal of weight limits, etc.).
 
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