South Western Railway - Chaos

[Southernman46]

Now if we're talking Jurassic - the area around Yeovil Junction station has some spectacular examples of Bridport Sands (the stuff that ends falling into the sea regularly narrowly missing (or not) foolhardy visitors to those beaches. I give you my particular favourite geology...........

 

Wikipediahttps://en.wikipedia.org/wiki/Bridport_Sand_Formation

 

How's that for thread drift 😀

[The Stationmaster]

8 hours ago, phil-b259 said:

 

Thats why the Greenford system has two big battery banks at West Ealing.

 

In such a situation you don't need a heavy duty national grid connection - a modest one which is continually trickle charging the battery banks at the charging location is enough. Then, just as used to happen with steam locomotives where a modest water supply was used to fill up a large tank on a water tower, when the train arrives all that stored electricity (or water in the case of a steam loco) gets poured into the train in minutes.

 

 

So 6 recharges each of less that 3 minutes duration will fully restore the total mileage capacity of the train's batteries?  That's a very different situation from the one originally explained by Vivarail in their technical descriptions of their system's capabilities.

[Dunsignalling]

8 hours ago, Gwiwer said:

Due (directly or otherwise) to the constantly-shifting substrata of Jurassic clays beneath the line.  There have been many slips west of Salisbury in recent years with the Gillingham and Axe Valley areas among the worst affected.  

 

My last conversation with anyone in SWR who might have had a clue where the future lay ended with the words "we don't know" in the context of what might replace the 159 fleet both in terms of hardware and traction type.  It's a long way from Worting to Exeter but wires would make some sort of sense.  Most current-generation stock is capable of bi-mode operation so third-rail to Basingstoke / Worting and overheads from there westwards.  If the GWR route was to be electrified beyond Newbury, as indeed it should or even must be at some future time, this would link systems at St. Davids.  Infill would then include the missing routes via Bath and Temple Meads.  Add Castle Cary to Yeovil to maintain operational flexibility.  

 

The greatest problem is money not technology.  "Unobtanium" will not serve the railways into the future.  Not even into tomorrow.  Research and development is all well and good - and essential - but 25kVac is proven technology and compatible with much of the national network.  

 

Reliability on the SWR route is as much a factor of its legacy, with long sections of single line, as anything else.  The geology and climate are not doing it any favours right now either but those we cannot change.  It only takes a slight hiccup to impact train running many miles away.  My most recent trip that way was only around 15 minutes late at Salisbury (having been delayed by congestion around London) but was sacrificed to allow other trains to run punctually and lost every booked cross.  It arrived at St. Davids an hour behind time and with just a single minute to turn back and return.  

 

Of topic somewhat but as we mostly know such delays can have wide-ranging effects.  My wife commutes weekly between Penzance and London and was recently delayed by over an hour.  Her train was on time until the Westbury avoiding line where it was checked because a late-running Gloucester - Weymouth service was let out ahead of it.  That, being late, was then stopped at Clink Road because an aggregate train had been allowed through Frome first.  The Penzance was in a queue.  Being delayed it was then out of pathway at Castle Cary where it was held for a Weymouth - Gloucester to come off the branch first; that in turn was running late because of the cross at Maiden Newton holding it up for 12 minutes.  The Penzance was then well and truly out of path but still only around 20 late however it ended up behind other trains, had to wait for a platform at St. Davids and missed its single-line crosses in Cornwall.  Delays at Maiden Newton and somewhere in the Gloucester area, nowhere near its line of route, had caused it to arrive an hour behind time.  

 

 

 

The nearest to consistent regulating that nowadays happens on the WoE is sacrificing down trains to keep up ones running, despite clear evidence dating back to the original introduction of the hourly service, that up trains (for whatever reason) generally have a better chance of making up lost time.

 

Unfortunately, it only works for the odd late runner, if delays are happening to all or most down trains further up, one soon gets to a point where they don't get to St. Davids in time for their return slot. The smart regulators steal some time by putting them in the bay at Central and get the passengers up on an Exmouth, but there don't seem to be many smart regulators any more and I suspect it only happens when Exeter Panel suggest it!

 

In days of yore (mine) there was an agreed regulating plan, which I and other siggies took part in devising. Up trains only got priority Pinhoe to Honiton if the down was 17 or more minutes late (assuming the up was on time). Not perfect, but it certainly worked better than the random approach evident these days. AIUI, it is still officially in use, though there's seldom any indication that anyone knows about it!

 

One other critical point is that crosses at Honiton are supposed to coincide with others at Gillingham, the two stations being an hours running apart. Lose sight of that, and one is truly beyond hope.....

 

Edited August 25 by Dunsignalling

[phil-b259]

7 hours ago, The Stationmaster said:

So 6 recharges each of less that 3 minutes duration will fully restore the total mileage capacity of the train's batteries?  That's a very different situation from the one originally explained by Vivarail in their technical descriptions of their system's capabilities.

 

Thats not what I said - and in any case the comments you have selected are referring to the problem where in rural location the size of the National Grids 'pipe' is smaller than you would get in an urban / industrialised area.

 

However with a sufficiently large battery capacity then there is no need for it to be fully recharged between each trip - the critical requirement is whether over the day the battery retains enough charge to operate the service reliably (even if a longer charging period is required before the unit returns to the depot at the end of the day) and whether that performance / charging regime significantly shortens the battery life such that the batteries have to frequently be replaced.

 

As I'm not part of the trial I obviously cannot say for sure that these aspects have been found to be satisfactory - but the mood music which has been emanating from the project suggests that it has been exceeding the expectations of the designers and consequently, with continued development to enhance the system, it can play a role in the de-carbonisation of motive power in the future.

 

 

 

[phil-b259]

11 hours ago, Northmoor said:

Mmm, yes, but considerably more expensive to install the 21st century infrastructure than a 1/2" water pipe and a water tank.

 

What I read from your description of the Greenford application is that there is power supply to feed a battery, to charge another battery, to run a very small, specialist fleet of trains (which will thus have disproportionate support costs).  In any other country they'd have just strung up some wires, whereas in Britain we keep up the search for "Silver Bullets and Unobtainium" - anything other than actual electrification - rather than maintain the skills to do electrification economically, by, err, doing electrification.  I only hope the Greenford is successful works so that it can be implemented on other Thames Valley branches, so the micro-fleet can be grown to reduce the support costs problem.

 

It should not be forgotten that the reason the Greenford branch was chosen to test the technology was down to practicality.

 

Before the system could be used to carry passengers it had to undergo a lengthy testing period - doing this on a double tracked line but one that was isolated operationally from the main network meant you could easily slot test trains in between the ordinary diesel trains during the initial testing phase.

 

Equally when it came to the later phase of testing with passengers it allowed that testing to take place with no alterations to the setup, plus if substantial upgrades were done and non passenger test running was again required that could be done between the regular diesel shuttle thereby allowing passenger services to be maintained.

 

More broadly you cannot escape the fact that OLE is expensive to install and adding it to a branch line served by a single 2 car unit doesn't make economic sense - particularly when much more intensively used InterCity routes still lack it! With Reading depot still needing to house diesel units for other routes (and the Marlow branch incapable of taking anything more than a 2 car unit) then its no surprise that the Greenford branch lacks wires even if it is in London and connects to the electrified GWML.

 

In the longer term however I don't see the battery technology being used in isolation - something that quite a few folk seem to be fixated on when discussing it on here. It should be remembered that the Greenford setup is a trial! and NOT the squadron deployment of a mature technology. In such trials its the norm for 'proven' technology (e.g. having your 2nd hand battery train fitted out for 25KV OLE so it can use that to get to / from a depot) to be left out

 

Therefore if this new technology is deployed in new build trains I expect the battery technology to be accompanied with a 25KV OLE or 750V DC 3rd Rail provision (allowing use to be made of what electrification currently exists) and potentially some discontinuous electrification being added where traffic volumes or speed profiles mean full electrification of the entire route is either so far down the list of priorities that it won't happen for decades or where its simply uneconomic.

[Wickham Green too]

2 hours ago, phil-b259 said:

... having your 2nd hand battery train fitted out for 25KV OLE so it can use that to get to / from a depot) ...

Rather than carting a heavy unused transformer up and down the branch all day would it not make sense to fit the thing with compatible couplings ( shock-horror ) so that it could be hauled to the depot by something else whenever necessary ??!?

[Artless Bodger]

2 hours ago, phil-b259 said:

(and the Marlow branch incapable of taking anything more than a 2 car unit)

I've probably missed something here, in which case please excuse my ignorance, but in the past (perhaps when redundant 319s were being proposed for WR electrification use, iirc reduced to 3 cars) I recall the 2 car limit on the Marlow line being put forward as a reason why it could not go 25kV OH, as 2 car units were not possible on 25kV. However some of the Clacton units were 2 car, so why had 2 car become a problem? Unless it was down to the plans to reuse exisiting units where the transformer and pantograph were on an intermediate vehicle?

[phil-b259]

2 hours ago, Artless Bodger said:

I've probably missed something here, in which case please excuse my ignorance, but in the past (perhaps when redundant 319s were being proposed for WR electrification use, iirc reduced to 3 cars) I recall the 2 car limit on the Marlow line being put forward as a reason why it could not go 25kV OH, as 2 car units were not possible on 25kV. However some of the Clacton units were 2 car, so why had 2 car become a problem? Unless it was down to the plans to reuse exisiting units where the transformer and pantograph were on an intermediate vehicle?

 

The issue with the 319s is simply that the pantograph / transformer is mounted on an intermediate passenger carrying vehicle which does not have a driving cab! To reduce the 319 to a 2 car unit therefore needs a massive amount of work moving the entire OLE stuff to a driving car or equally fitting a driving cab to the intermediate car.

 

More broadly the issue is not a 2 car 25KV OLE unit per say* (as you note the 'Clacton' units did come in 2 car formation originally), its more the case that in general if the line is busy enough to warrant electrification it needs more than 2 car units to accommodate passenger demand. 

 

As such its important to note that the 2 car 'Clacton' units were not ordered with the intention that they would be running around solo! - they were ordered so the operator could add some extra capacity to 4 or 8 car trains to make 6 or 10 car trains at peak times but could shorten said trains during the off peak period.

 

IIRC in later years these 2 car units were made into 4 car units to cope with increasing passenger demand by the insertion of converted Mk1 hauled stock rather than building new EMUs to cater for growth

 

In more recent times the trend has been to not to have 'spare' stock sitting round and attach it for the peaks - increasingly its the case that a train is made up to a certain length at the depot and runs round like that all day (with the obvious exception of multi-portion trains splitting / dividing on route to different start / end points.

 

Now technically you could have a 12 car train made up of 5 6 x 2 car units - but this wastes a lots of passenger space because of all the driving cabs and it also means you end up with far more accessible toilets (which also take up valuable passenger space) than you need.

 

Hence no operator in recent times has ordered anything less than a 3 car unit - and if we take the Thames Valley in particular it happens that a 4 car unit is the most efficient size 'base unit'. Its also important to note that it would also fit the Henley, Slough and possibly Greenford branch with selective door operation / some modest platform extensions and the only line it won't fit is the Marlow branch which means its not worth GWR ordering any 2 car straight EMUs.

 

However if said 2 car unit becomes a battery / OLE equipped unit the calculation might well change as said unit could also be potentially used in other places across the UK and as such it becomes a viable thing for train manufacturers to offer as an option. 

 

 

* As each pantograph passes it creates disturbance in the OLE - if the contact wire is still disturbed when the next photograph comes along you increase the risk of a dewirement / entanglement / pantograph damage. Hence if the OLE is judged to be rather flimsy then there may be restrictions on how close together two raised pantographs may be -with that distance increasing as speeds rise, which in turn may impose minimum length requirements for trains.

Edited August 25 by phil-b259

[phil-b259]

1 hour ago, Wickham Green too said:

Rather than carting a heavy unused transformer up and down the branch all day would it not make sense to fit the thing with compatible couplings ( shock-horror ) so that it could be hauled to the depot by something else whenever necessary ??!?

 

No! manufacturers are not interested in supplying tiny bespoke fleets while operators dislike having limitations for diagramming reasons. You should note that the original class 800 fleet provided to GWR has had their engines updated so they are now exactly the same in output to the 802 fleet precisely because it was a massive headache to have the 800s unable to subsitue for the 800s operationally speaking.

 

That said if the rest of the Thames Valley branches get rebuilt D stock as their battery train then they will probably lack 25KV provision - but given the way things are developing in de-carbonisation terms and the need to replace the 15X fleet over the coming decade there is the opportunity for a train manufacturer to offer a brand new combined battery plus 25KV OLE design based around the fast charge technology for use all over the UK.

 

Such a train could well find use on the Oxford - Paddington runs for example (removing the need to change to a diesel shuttle at Didcot) or take over Bedwyn runs from the IETs freeing up those for the longer distances they were designed around. It could also find use on services to Windermere (particularly if they run onto the 25KV network to Manchester). Matlock - Derby is another possibility in the future assuming wires continue up the MML as planned.

[Gwiwer]

1 hour ago, phil-b259 said:

technically you could have a 12 car train made up of 5 x 2 car units

That would be very technical.  I assume you mean 6x2-car units.  

 

The SR prohibited such a thing as the slight additional length which was required by having all those intermediate couplers (as opposed to the usual intermediate bar-couplers) could result in a train being over-length for platforms and signal sections.  You could have no more than five 2-car units coupled but you could have a 12-car train formed of 4x2-car and a 4-car.  

 

The Clacton 2-car units were originally specified to match the then level of demand and - again - platform length constraints.  Remember those 10-car trains replaced a steam loco plus eight and there was an expected upturn in traffic which indeed occurred at electrification.  It was felt, rightly, that Clacton could not manage with a single four-car unit especially at peak and holiday times; Clacton once saw large holiday crowds arriving by train.  The pattern devised was the split / attach at Thorpe-le-Soken with a 4-car to Walton and 6 cars to Clacton.  The 2-car units were strengthened to 4-car and the griddle cars were "downgraded' to seating only without catering (other than a trolley if you were lucky) as traffic patterns changed.  Some peak trains were 12-car but most were reduced to 8-car however more trains were offered overall.  Later still some units ran as three cars.  

 

There is no technical reason why a 2-car (or even a single car) unit cannot be run from 25kVac overhead.  Modern traction packages occupy less space than they once did so underfloor space, or lack of it, is less of an issue.  Global compatibility is required where possible.  Privatisation has seen this abandoned as each TOC has operated almost exclusively its own rolling stock in its own area meaning the need for one universal coupling and control system has been perceived as redundant.  Probably wrongly as it turns out.  

 

Where units are normally expected to run in multiple it is preferable to have through-gangways throughout the train.  The IETs have a problem here as do many other modern types.  Two 5-car units coupled means you are trapped in the unit you board.  Some passengers cannot access reserved seating because they board at a short platform where only the first unit is opened but their reservations are in the other set.  When a train formation is reversed as regularly happens passengers needing to alight at short platforms and whose reservations might be made correctly by the system (i.e. in the front unit) find themselves unable to alight if - for example - Coach A is at the back not the front.  Through-access was a problem on non-gangwayed slam-door types (and hauled stock too) but in many cases there the hapless passenger would open the door and hop down to the track if they were too far back.  

[phil-b259]

28 minutes ago, Gwiwer said:

 

Where units are normally expected to run in multiple it is preferable to have through-gangways throughout the train.  The IETs have a problem here as do many other modern types.  Two 5-car units coupled means you are trapped in the unit you board.  Some passengers cannot access reserved seating because they board at a short platform where only the first unit is opened but their reservations are in the other set.  When a train formation is reversed as regularly happens passengers needing to alight at short platforms and whose reservations might be made correctly by the system (i.e. in the front unit) find themselves unable to alight if - for example - Coach A is at the back not the front.  Through-access was a problem on non-gangwayed slam-door types (and hauled stock too) but in many cases there the hapless passenger would open the door and hop down to the track if they were too far back.  

 

The lack end gangways on IETs is somewhat less objectionable when you consider that no country in the world operates high speed (125mph or above) trains with gangways built into the ends as its virtually impossible to design one which is both aerodynamically efficient plus is structurally strong enough to maintain the structural integrity in a collision.

 

Yes in an ideal world you would do what Thameslink does and send lengthy fixed formation trains to all destinations - but as you get closer to populous areas line capacity becomes increasingly limited and as such shortish formations combining does allow more p[laces to receive high speed trains thereby becoming more attractive to passengers (who research has proven time and time again hate changing trains mid journey)

 

Its also the case that with the UK loading gauge the driving cabs of trains featuring end gangways can be rather constrained in terms of finding places for kit such as DOO monitors so I can see why from a drivers and operators perspectives designs with full width cabs might be favoured even though from a technical perspective end gangways are fairly easy to fit to suburban units.

 

 

Edited August 25 by phil-b259

[The Stationmaster]

1 hour ago, phil-b259 said:

 

No! manufacturers are not interested in supplying tiny bespoke fleets while operators dislike having limitations for diagramming reasons. You should note that the original class 800 fleet provided to GWR has had their engines updated so they are now exactly the same in output to the 802 fleet precisely because it was a massive headache to have the 800s unable to subsitue for the 800s operationally speaking.

 

That said if the rest of the Thames Valley branches get rebuilt D stock as their battery train then they will probably lack 25KV provision - but given the way things are developing in de-carbonisation terms and the need to replace the 15X fleet over the coming decade there is the opportunity for a train manufacturer to offer a brand new combined battery plus 25KV OLE design based around the fast charge technology for use all over the UK.

 

Such a train could well find use on the Oxford - Paddington runs for example (removing the need to change to a diesel shuttle at Didcot) or take over Bedwyn runs from the IETs freeing up those for the longer distances they were designed around. It could also find use on services to Windermere (particularly if they run onto the 25KV network to Manchester). Matlock - Derby is another possibility in the future assuming wires continue up the MML as planned.

There's a half hourly interval service of through trains between Oxford and Paddington during much of the day already - using IETs.  And as many changes from Oxford are listed to take place at Reading as  are listed to take place at Didcot.   The real failure of the intention (partly completed) to extend 25kv to Oxford was to create a surplus in the GWR 387 fleet although that has allowed part of the fleet to cover HEX workings plus various longer distance workings on the GWML (e.g Paddington - Cardiff).

 

The only reason IETs run to Bedwyn is because there were surplus sets left from the originally planned use of the fleet mainly as a consequence of changes to the electrification programme.  The fleet of 5 cars sets is now of course far more heavily used on workings it was not built for due to the enforced withdrawal of the 'Castle' HST trains from routes into the West of England.

 

On present information I still remain very sceptical of the use of any sort of battery powered set on the Thames Valley branches.  We have yet to see the important thing, the numbers.  How many amp hours these trains will use,  and how quickly they will be restored to full capacity by the charging system so far devised in the times available for recharging?   If the numbers, exist even only as calculations, then - as exactly VivaRail did in the past - there should be no problem with making those numbers public.  Obviously a trial is necessary to validate the numbers in a live working situation but as long as the numbers are not in the public domain I wonder why not because it is being implied that they are well beyond what VivaRail calculated and published.

[Pacific231G]

5 hours ago, phil-b259 said:

 

It should not be forgotten that the reason the Greenford branch was chosen to test the technology was down to practicality.

 

Before the system could be used to carry passengers it had to undergo a lengthy testing period - doing this on a double tracked line but one that was isolated operationally from the main network meant you could easily slot test trains in between the ordinary diesel trains during the initial testing phase.

 

Equally when it came to the later phase of testing with passengers it allowed that testing to take place with no alterations to the setup, plus if substantial upgrades were done and non passenger test running was again required that could be done between the regular diesel shuttle thereby allowing passenger services to be maintained.

 

More broadly you cannot escape the fact that OLE is expensive to install and adding it to a branch line served by a single 2 car unit doesn't make economic sense - particularly when much more intensively used InterCity routes still lack it! With Reading depot still needing to house diesel units for other routes (and the Marlow branch incapable of taking anything more than a 2 car unit) then its no surprise that the Greenford branch lacks wires even if it is in London and connects to the electrified GWML.

 

In the longer term however I don't see the battery technology being used in isolation - something that quite a few folk seem to be fixated on when discussing it on here. It should be remembered that the Greenford setup is a trial! and NOT the squadron deployment of a mature technology. In such trials its the norm for 'proven' technology (e.g. having your 2nd hand battery train fitted out for 25KV OLE so it can use that to get to / from a depot) to be left out

 

Therefore if this new technology is deployed in new build trains I expect the battery technology to be accompanied with a 25KV OLE or 750V DC 3rd Rail provision (allowing use to be made of what electrification currently exists) and potentially some discontinuous electrification being added where traffic volumes or speed profiles mean full electrification of the entire route is either so far down the list of priorities that it won't happen for decades or where its simply uneconomic.

Generally, I agree with you. The Greenford branch is double track as it also handles a reasonable amount of freight - all hauled by diesel locos- so you'd be installing two sets of catenary for a single three-car (in the case of the D stock) unit operating six days a week. There would also be a disproportionate amount of civil engineering required to lower the tracks through the  Drayton Green Tunnel (A concrete raft on which the main roads for a housing development sit so the roof couldn't be raised )

However, the proven charged range of these units is plenty long enough to get them from their branches to the relevant depot, easily so for the Thames Valley  branches, so fitting them with 25 kV OLE would be a huge and unnecessary cost.  Breakdowns are a different matter but they happen to any form of traction. I think the impact of power outages is being rather overstated. I've lived in Greenford for over thirty years and, in all that time, have  had one outage that lasted about an hour (due to a fire in the local substation) and a few far shorter ones.

Edited August 25 by Pacific231G

[The Stationmaster]

1 minute ago, Pacific231G said:

Generally, I agree with you. The Greenford branch is double track as it also handles a reasonable amount of freight - all hauled by diesel locos- so you'd be installing two sets of catenary for a single three-car unit. There would also be a disproportionate amount of civil engineering required to lower the tracks through the  Drayton Green Tunnel (A concrete raft on which the main roads for a housing development sit)

However, the proven charged range of these units is plenty long enough to get them from their branches to the relevant depot, easily so for the Thames Valley  branches, so fitting them with 25 kV OLE would be a huge and unnecessary cost.  Breakdowns are a different matter but they happen to any form of traction. I think the impact of power outages is being rather overstated. I've lived in Greenford for over thirty years and, in all that time, have  had one outage that lasted about an hour (due to a fire in the local substation) and a few far shorter ones.

In view of the date when the covered way at Drayton Green was built it surety should have included 25kv clearance as that was normal BR design practice at that time?  I see the current Sectional Appendix refers to it as 'Drayton Green Tunnel' so maybe its status has been altered in order to avoid providing the continuous lighting it originally had?

[phil-b259]

1 hour ago, Pacific231G said:

Generally, I agree with you. The Greenford branch is double track as it also handles a reasonable amount of freight - all hauled by diesel locos- so you'd be installing two sets of catenary for a single three-car (in the case of the D stock) unit operating six days a week. There would also be a disproportionate amount of civil engineering required to lower the tracks through the  Drayton Green Tunnel (A concrete raft on which the main roads for a housing development sit so the roof couldn't be raised )

However, the proven charged range of these units is plenty long enough to get them from their branches to the relevant depot, easily so for the Thames Valley  branches, so fitting them with 25 kV OLE would be a huge and unnecessary cost.  Breakdowns are a different matter but they happen to any form of traction. I think the impact of power outages is being rather overstated. I've lived in Greenford for over thirty years and, in all that time, have  had one outage that lasted about an hour (due to a fire in the local substation) and a few far shorter ones.

 

Whilst I agree in the context of Greenford, its worth remembering that if these trials result in a mainstream manufacturer like Alstom, Hiatchi, CAF, etc going to the trouble to produce a new build battery train they are going to want to make sure it caters for other markets too! As such I would expect the basic design to have 25KV OLE and 750VDC provision built in to the design to give maximum flexibility and not be restricted to what suits the Greenford branch.

 

As ever I remind people the Greenford trail is NOT simply a "how can we replace the diesels currently used on the Greenford branch with some non fossil fuelled unit" question - its "can a fast charge system work reliably when applied to a real world passenger operation. The use of the Greenford branch, the recycling of ex London Underground stock, etc are merely because they happened to be the best way of demonstrating / testing the technology - they are not indicative of what the future may hold if the trials prove to be a success.

 

 

Edited August 25 by phil-b259

[Artless Bodger]

Thanks to phil-b259, Gwiwer and The Stationmaster for their information regarding the issue of 2 car 25kV units etc.