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Chiltern Railways Electrification

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Zomboid

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Fast charging from a specially installed charger is different from drawing power from existing infrastructure that is designed to power trains on the move – my question is more about whether the LU system can supply power fast enough to a train in motion rather than whether the train can take that power in.
And that'll depend on the power demand of the trains. Do Chiltern need to run anything especially long up there compared to the underground? Bearing in mind that it was possible to build a 750V DC system with enough power to run 373s and 92s, it would be quite something if charging a 4 car BEMU needed more energy than that - so it might need an upgrade, but I would expect that sufficient power could be delivered via the 4 rail system.
 
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Upgrading the 4th rail for extra demand is completely plausible and not especially complicated. Merseyrails system was upgraded in 2019 for their new trains involving new 33/11kV grid supply points and new AC/DC substations.

Another concern i have is with the idea of static charging from 25kV OLE. OLE systems are designed to dram more current in motion than at stand, so this could put serious operational restrictions if trains have to stand around for a long time. Conductor rail systems are good for static charging while OLE is better for charging in motion.

Greenford style fast chargers might actually make more sense at marylebone with stretches of 25kV elsewhere to be used in motion
 

Snow1964

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How much power is available from the LU metals? Bearing in mind that only about one-third of the route from Marylebone to Aylesbury Vale Parkway is electrified ... that would mean the train would need to effectively draw 3 times the power it needs to run in order to recharge the battery at twice the rate it will use it ... is that realistic? (I'm not an electrical engineer, so I don't know if it is or not!)
I'm not an electrical engineer either, but that obviously depends on what (if any) other charging facilities are in use.

If Marylebone platforms are also included, it should be okay I think.
I am not an electrical engineer either, but if the platforms at Marylebone are overhead electrified (even if the station throat and approach tunnel area uses the slimline solid bar type conductor rather than wires, and would need to go part way towards tunnels to protect against raised pantographs if only did platform area) then can charge whilst stationary at the terminus. Time wise unless there are stupidly short turnarounds could easily be 15-20% of duration of round trip.

I am fairly sure that a train with batteries can get anything from 15-30% of its energy from regeneration (slowing down and going downhill) depending on line gradient profile, slowing for speed restrictions and stopping pattern. It's not as simple as third of line is electrified therefore need 3 times the power on electrified bit.
 
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Zomboid

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Time wise unless there are stupidly short turnarounds could easily be 15-20% of duration of round trip.
This being an obvious flaw with batteries - you can't do a quick turn round if there's disruption to the timetable because you need to charge the batteries. Hopefully some allowance for that is made in the design.
 

N1

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I am not an electrical engineer either, but if the platforms at Marylebone are overhead electrified (even if the station throat and approach tunnel area uses the slimline solid bar type conductor rather than wires, and would need to go part way towards tunnels to protect against raised pantographs if only did platform area) then can charge whilst stationary at the terminus. Time wise unless there are stupidly short turnarounds could easily be 15-20% of duration of round trip.

I am fairly sure that a train with batteries can get anything from 15-30% of its energy from regeneration (slowing down and going downhill) depending on line gradient profile, slowing for speed restrictions and stopping pattern. It's not as simple as third of line is electrified therefore need 3 times the power on electrified bit.
Seems to me the easiest option would just be to run Aylesbury services into Baker Street, not Marylebone, no issue with mixing electrification costs.

You can also add 4th rail electrification at Aylesbury Vale Parkway only energised when the train is in the station.
 

Eurostarosaur

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I'm not a railway expert, or an electrical engineer, and no offence but if I was the government I would probably want 1. minimum spend 2. minimum fuss 3. minimum risk 4. non-speculative tech. So I feel like a few of the ideas above are a bit too wacky for them.

The GWR and Hitachi battery train trials have both demonstrated battery range of around 100 miles. As far as I'm aware Marylebone to Aylesbury is only 39 miles and Birmingham is 99 miles. GWR have been using rapid charging in around 4 mins. So not hard to imagine charge at Marylebone, charge at Aylesbury, charge at Birmingham. Can also do High Wycombe, Oxford, West Ruislip even if needed. Birmingham trains could stop for a few mins to charge at a station such as High Wycombe or Warwick, I've always found the Chiltern schedule to be rather well padded as it is. The infrastructure required would not need huge cost and closures for months or years, perhaps except a cost for the power network investment and charging in the station.

I'm sure it's a lot more complicated than that, but the idea of fitting rails like the London Underground, or overhead wiring at tens of millions of pounds each mile really could make it very unpalatable to the government. If Chiltern want this done before the diesel trains fully pack up, then I think it has to be batteries + fast chargers.

Am I confused or do Chiltern already have a tender out for the new trains?
 
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Seems to me the easiest option would just be to run Aylesbury services into Baker Street, not Marylebone, no issue with mixing electrification costs.
That would also probably free up a bit of space at Marylebone too, to make full use of a new fleet on the Wycombe line too
 

Class15

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Seems to me the easiest option would just be to run Aylesbury services into Baker Street, not Marylebone, no issue with mixing electrification costs.

You can also add 4th rail electrification at Aylesbury Vale Parkway only energised when the train is in the station.
By this do you mean making it part of the Met? I would absolutely support this, assuming it meant electrification from Amersham to Aylesbury!
 

Mgameing123

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How about we stopped making short term cuts and just electrify it fully with 25 kv AC like any other line with it's size. The UK government needs to stop making short term cost cutting measures that have negative impact in the future.

Like my local line has way fewer trains than the Chiltern line and is getting fully electrified.

There is no good excuse to not electrify the Chiltern line!
 

sad1e

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How about we stopped making short term cuts and just electrify it fully with 25 kv AC like any other line with it's size. The UK government needs to stop making short term cost cutting measures that have negative impact in the future.
Exactly , if this goes ahead I would place a hefty bet that there will be problems with discontinuous electrification being used over continuous within 10 years.

The only usecase for discontinuous electrification I can see for Chiltern is the Aylesbury via Met services , Trying to rely on discontinuous electrification for the mainline services seems quite unwise as it is an unproven technology for Longer services.

You wouldn't exactly want it to go wrong during one of the many times the WCML decides not to play along.

And If they're able to fit Bar style OHLE in the Thameslink tunnels and at St pancras surely they could be able to fit it into the Marylebone tunnels.
 

HSTEd

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How about we stopped making short term cuts and just electrify it fully with 25 kv AC like any other line with it's size. The UK government needs to stop making short term cost cutting measures that have negative impact in the future.

Like my local line has way fewer trains than the Chiltern line and is getting fully electrified.

There is no good excuse to not electrify the Chiltern line!
The problem is the 25kV programme has seen such cost growh that the electrification will never be able to defray its costs.

Battery trains allow the bulk of these costs to be avoided in exchange for comparatively minor operational inconvenience.
 

Trainbike46

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The problem is that the Chiltern route really should have been electrified in the 80s or 90s. However it wasn't, and something really should be implemented in time that new (B)EMUs can replace the 16x fleet - buying new diesel and locking in another 35 years of no progress really isn't an option, and there aren't any DMUs going spare elsewhere either.

I don't see any feasible way for full electrification in time for that, so BEMUs with charging infrastructure* is the way to go.

* so targeted 25kV OHLE, using the existing LU 4th rail, or I guess whatever other charging solution gets used.
 

Snow1964

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The problem is the 25kV programme has seen such cost growh that the electrification will never be able to defray its costs.
I think this statement needs a huge caveat

It appears that in Europe where they operate rolling programs cost growth is not excessive.

It is just the dumb way some schemes in UK have been organised and specified, with inconsistent non standard equipment, having start/stop then disperse team, then try and restart with no continuity. With equipment being bought then inefficient on/off usage with no application of long term optimisation.

Of course if don't have longer term rolling stock framework contracts, but keep choosing non standard small batches of BEMUs, they are not going to be cost optimised either.
 

HSTEd

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I think this statement needs a huge caveat

It appears that in Europe where they operate rolling programs cost growth is not excessive.

It is just the dumb way some schemes in UK have been organised and specified, with inconsistent non standard equipment, having start/stop then disperse team, then try and restart with no continuity. With equipment being bought then inefficient on/off usage with no application of long term optimisation.
The problem is now more severe than that.
Most routes that are going to be worth electrifying even in a pessimistic BEMU scenario have already been done. Even if costs get as low as they are on the continent.

There is a quantity of schemes remaining to be done, but there isn't that much remaining.

A rolling scheme, by its very nature, will require a continuous stream of work for a decade or more before its supporters will brook any discussion about whether it has succeeded.

But by then, there will be very little work left to do which will benefit from those cost savings - if they occur in the first place.

Of course if don't have longer term rolling stock framework contracts, but keep choosing non standard small batches of BEMUs, they are not going to be cost optimised either.

Well that's caused by the governments desire to pretend there is a competitive market in rolling stock made in the UK, when the UK market is far too small for such a thing to exist.
 

The exile

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I think this statement needs a huge caveat

It appears that in Europe where they operate rolling programs cost growth is not excessive.
One should recognise that most European countries are starting from a better place than we can. Many operate with lower voltages (= lower clearances) on networks with more generous structure gauges, with far fewer pre-war overbridges - indeed far fewer historic structures all round. Most have already done most of the hard bits (big built up areas -OK, it’s definitely our fault that we haven’t). Our short sightedness is, however, really evidenced by our being about to open (eventually) EWR as a diesel only railway.
 

brad465

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If this article is anything to go by, I doubt any form of electrification is being approved for Chiltern anytime soon:


Ministers are not planning to electrify any more of the UK’s railway lines in order to focus investment on other projects such as HS2, the transport secretary said. Heidi Alexander said any further electrification of lines is “not affordable right now”, despite industry anger over decisions that have led to key routes being left with stretches that require diesel trains.
 

Mgameing123

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One should recognise that most European countries are starting from a better place than we can. Many operate with lower voltages (= lower clearances) on networks with more generous structure gauges, with far fewer pre-war overbridges - indeed far fewer historic structures all round. Most have already done most of the hard bits (big built up areas -OK, it’s definitely our fault that we haven’t). Our short sightedness is, however, really evidenced by our being about to open (eventually) EWR as a diesel only railway.
Lets compare the UK with Denmark then who both use 25 kv AC
 
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that's sort of cherry-picking though. Denmark has been slow to electrify. Most of France is 25kV as well (not just LGVs)
 

The Pelican

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Chiltern was fairly unlucky in electrification history terms, as there are lots of existing electrified lines which don't get anything like as many trains an hour as Marylebone does- but its Birmingham trains, and some of the High Wycombe trains, used to run to Paddington via Greenford instead of Marylebone. So any attempt to wire between London and Banbury pre- 1960s would probably have gone from West Ruislip to Greenford to Paddington instead. Then in the 1980s electrification round it was behind the ECML, then behind the GWML and MML in the 2010s-20s round. I expect it will get done soon though!
 

sad1e

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High Wycombe trains, used to run to Paddington via Greenford
Wouldn't they have used the now severed Acton - Northolt line (New North Mainline) to go direct into Paddington , Via Greenford would be rather slow and includes single track sections near West Ealing.
 

Mikey C

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If this article is anything to go by, I doubt any form of electrification is being approved for Chiltern anytime soon:

The Chiltern proposal is for the bare minimum of electrification, mainly so that batteries can be recharged, and all in easy locations. If the government can't even afford that, then they'll have to order some new DMUs which would be humiliating for the government's green credentials.
 

The Pelican

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Yes, I meant using the whole New North Mainline from West Ruislip past Greenford, and on past Hanger Lane to Old Oak Common, not via Castlebar Park and Ealing Broadway. I did it on a diverted HST slightly over ten years ago!
 

Mgameing123

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The Chiltern proposal is for the bare minimum of electrification, mainly so that batteries can be recharged, and all in easy locations. If the government can't even afford that, then they'll have to order some new DMUs which would be humiliating for the government's green credentials.
Or they can free up some DMU’s elsewhere that can come to Chiltern that can atleast reduce the amount of Class 165’s needed so that more of the fleet can be salvaged for spare parts.
 

JonathanH

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Iirc in the 1980s serious consideration was given to closing Marylebone and converting to busses.
Yes, but the level of service, and custom then was such that it could reasonably have been accommodated on the Metropolitan Line, and at Paddington.
 

GRALISTAIR

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Yes, but the level of service, and custom then was such that it could reasonably have been accommodated on the Metropolitan Line, and at Paddington.
Yes. So absolutely no chance of making a bus case for electrification in the 70s, 80s or 90s then.
 
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