The Anonymous Widower

Running Battery Electric Trains Between London Marylebone And Aylesbury

This post was suggested by Fenline Scouser in a comment to Vivarail Targets Overseas Markets, where they said.

I have long thought that one UK application that would make sense is the Marylebone – Aylesbury via Harrow on the Hill service, the intermediate electrified section lending itself to full recharge on each trip. ? stabling facility at Aylesbury with overnight charging.

It does look to be an idea worth pursuing.

Current And Future Services

Currently, the services between London Marylebone and Aylesbury are as follows.

  • London Marylebone and Aylesbury via High Wycombe
  • London Marylebone and Aylesbury via Amersham
  • London Marylebone and Aylesbury Vale Parkway via Amersham

All services are one train per hour (tph)

In the future, it is planned to extend the Aylesbury Vale Parkway service to Milton Keynes, according to information I found on the East West Rail web site.

  • It looks like the service will go via High Wycombe, Saunderton, Princes Risborough, Monks Risborough, Little Kimble, Aylesbury, Aylesbury Vale Parkway, Winslow and Bletchley.
  • The service will have a frequency of 1 tph.
  • Time between Milton Keynes and Aylesbury is quoted as 33 minutes.
  • Time between High Wycombe and Milton Keynes is quoted as 63 minutes.

Will this leave the Marylebone and Aylesbury are as follows?

  • 1 tph – London Marylebone and Aylesbury via High Wycombe.
  • 2 tph – London Marylebone and Aylesbury via Amersham

Passengers between London Marylebone and Aylesbury would have the same service.


These are a few distances, of which some have been estimated.

  • London Marylebone and Harrow-on-the-Hill – 9.18 miles.chains
  • Amersham and Harrow-on-the-Hill – 14.27 miles.chains – Electrified
  • Aylesbury and Amersham – 15.23 miles.chains
  • London Marylebone and High Wycombe – 28.11 miles.chains
  • Aylesbury and High Wycombe – 15.28 miles.chains
  • Aylesbury and Aylesbury Vale Parkway – 2.25 miles.chains
  • Aylesbury Vale Parkway and Calvert – 8.19 miles.chains
  • Aylesbury and Milton Keynes – 16.40 miles.chains – Estimated

Note that there are eighty chains to the mile.

Hitachi’s Regional Battery Train

Hitachi’s Regional Battery Train, is the only battery electric train intended for the UK network for which a detailed specification has been released.

This infographic from Hitachi gives the specification.

Note that ninety kilometres is fifty-six miles.

I would suspect that battery trains from other manufacturers, like Bombardier, CAF and Stadler, will have a similar specification.

Battery Electric Trains Between London Marylebone And Aylesbury

I’ll take each possible route in turn.

London Marylebone And Aylesbury Via Amersham

The three sections of the route are as follows.

  • London Marylebone and Harrow-on-the-Hill – 9.23 miles – Not Electrified
  • Harrow-on-the-Hill and Amersham – 14.34 – Electrified
  • Amersham and Aylesbury – 15.29 miles – Not Electrified


  1. The total distance is 38.85 miles
  2. A typical service takes just under twenty minutes to travel between Harrow-on-the-Hill and Amersham. This should be enough to fully charge the batteries.
  3. A train going South from Harrow-on-the-Hill could reach London Marylebone and return.
  4. A train going North from Amersham could reach Aylesbury and return.

I am fairly confident, that a battery electric train, with the range of a Hitachi Regional Battery Train could work this route.

London Marylebone And Aylesbury Vale Parkway Via Amersham

The four sections of the route are as follows.

  • London Marylebone and Harrow-on-the-Hill – 9.23 miles – Not Electrified
  • Harrow-on-the-Hill and Amersham – 14.34 – Electrified
  • Amersham and Aylesbury – 15.29 miles – Not Electrified
  • Aylesbury and Aylesbury Vale Parkway – 2.31 miles – Not Electrified


  1. The total distance is 41.16 miles
  2. A typical service takes just under twenty minutes to travel between Harrow-on-the-Hill and Amersham. This should be enough to fully charge the batteries.
  3. A train going South from Harrow-on-the-Hill could reach London Marylebone and return.
  4. A train going North from Amersham could reach Aylesbury Vale Parkway and return.

I am fairly confident, that a battery electric train, with the range of a Hitachi Regional Battery Train could work this route.

London Marylebone And Aylesbury Via High Wycombe

The two sections of the route are as follows.

  • London Marylebone and High Wycombe- 28.14 miles – Not Electrified
  • High Wycombe and Aylesbury – 15.35 miles – Not Electrified


  1. The total distance is 43.50 miles
  2. There is no electrification to charge the trains.

A battery electric train, with the range of a Hitachi Regional Battery Train will need charging to work this route.

However, with charging at both ends, this would be a route for a battery electric train.

At the London Marylebone end, there are two possible solutions.

  • Electrify the station traditionally, together with perhaps the tracks as far as Neasden, where the routes split. Either 750 VDC third-rail or 25 KVAC overhead electrification could be used.
  • Fit fast charging systems into all the platforms at the station.


  1. Turnround times in Marylebone station are typically nine minutes or more, so using a charging system should be possible.
  2. Power for the electrification should not be a problem, as the station is close to one of London’s central electricity hubs at Lisson Grove by the Regent’s Canal.

The final decision at Marylebone, would be one for the engineers and accountants.

At the Aylesbury end, it should be noted that much of the under twenty miles of track between Princes Risborough and Aylesbury and on to Aylesbury Vale Parkway and Calvert us single-track.

So why not electrify from Princes Risborough and Calvert, where the route joins the East West Railway?

The electrification in Aylesbury station could also be used to top-up trains going to London via Amersham.

I would use 25 KVAC overhead electrification, using lightweight gantries like these, which use laminated wood for the overhead structure.

There is also a video.

Electrification doesn’t have to be ugly and out-of-character with the surroundings.

London Marylebone And Milton Keynes Via High Wycombe, Aylesbury and Aylesbury Vale Parkway

The three sections of the route are as follows.

  • London Marylebone and High Wycombe- 28.14 miles – Not Electrified
  • High Wycombe and Aylesbury – 15.35 miles – Not Electrified
  • Aylesbury and Milton Keynes – 16.50 miles – Partially Electrified


  1. The total distance is sixty miles
  2. There is some electrification to charge the trains between Bletchley and Milton Keynes.

A battery electric train, with the range of a Hitachi Regional Battery Train should be able to work this route, if they can work London Marylebone and Aylesbury, with charging at Aylesbury.

Milton Keynes Central is a fully-electrified station.

The picture shows Platform 2A, which is South-facing electrified, five-car platform, which could be used by the Chiltern service.

Train Specification


  • Chiltern Railway’s workhorse is a Class 168 train, which is a diesel multiple unit of up to four cars, with a 100 mph operating speed.
  • The longest leg without electrification could be London Marylebone and Aylesbury via High Wycombe, which is 43.5 miles.
  • Hitachi’s Regional Battery Train has a range of fifty-six miles.
  • As there is a need to work with London Underground electrification, a dual-voltage train will be needed.

So a battery electric train with this specification would probably be ideal.

  • Four cars
  • Ability to work with both 750 VDC third-rail and 25 KVAC overhead electrification.
  • 100 mph operating speed.
  • Battery range of perhaps 55 miles.

Could the specification fit a battery-equipped Class 385 train, which will probably be built for Scotland?


I am convinced that battery electric trains can run between London Marylebone and Aylesbury, Aylesbury Vale Parkway and Milton Keynes stations.

The following would be needed.

  • A battery electric range of perhaps fifty-five miles.
  • Some form of charging at Marylebone and Aylesbury stations.

I would electrify, the single-track route between Princes Risborough and Aylesbury Vale Parkway.

September 4, 2020 Posted by | Transport | , , , , , , , , , , , | Leave a comment

Hertfordshire County Council’s Aspiration For A Watford Junction And Aylesbury Service

This article on Ian Visits is entitled Watford Junction Station Could Become A “Super-Hub”.

This is the introductory paragraph.

A new Watford Junction to Aylesbury rail service, along with a new link between Stevenage and Luton are two of the proposals being put forward by Hertfordshire Council.

The proposals are contained in this document on the Hertfordshire County Council web site, which is entitled Rail Strategy.

In TfL Seeks New Procurement Plan For Metropolitan Line Extension, I proposed a service run by Chiltern Railways between Watford Junction and Amersham stations.

The rest of this article is a rewrite of part of that linked post, which explores the possibilities of a service between Watford Junction and Aylesbury stations.

This Was My Original Simple  Proposal

I think it would be possible to design a simpler link with the following characteristics.

  • Watford station would remain open.
  • A four trains per hour (tph) link would run all day between Watford Junction and Amersham stations.
  • Stops would be at Watford High Street, Vicarage RoadCassiobridge, Croxley, Rickmansworth, Chorleywood and Chalfont & Latimer.

No-one would get a worse service than currently and the new stations of Cassiobridge and Vicarage Road, would make rail an alternative for many travellers.

The cross-Watford service would give access to these London services.

  • Chiltern at all stations between Croxley and Amersham.
  • London Midland at Watford Junction.
  • Metropolitan Line at Croxley, Rickmansworth and Amersham.
  • Virgin Trains at Watford Junction,
  • Watford DC Line at Watford High Street and Watford Junction

The Bakerloo Line at Watford Junction and Watford High Street, could possibly be added, if the line is extended. Which I doubt, it will be!

Hertfordshire is proposing the terminal is Aylesbury, which seems to be a good idea. But I’ll examine that later.

The next few sections, will cover various issues with the route.

New Track

There would need to be new track between Croxley and Watford High Street stations.

Will The New Stations Have Two Platforms?

All proposals have shown new stations on the new track at Cassiobridge and Vicarage Road.

I believe that money can be saved by creating two much simpler stations.

  • Only one platform, but probably an island platform with two faces like Watford High Street station.
  • No expensive footbridge if possible.
  • Only one lift.

Cassiobridge would be more complicated because of the viaduct connecting the line towards Croxley station.

This visualisation shows the viaduct and the location of Cassiobridge station.


Cassiobridge station will be behind the trees towards the top-right of the image.

Would The New Track Be Single Or Double-Track?

There is space for double-track and the two ends of the route are already electrified double-track.

But surely the viaduct shown above would be much more affordable, if it were to be built for only one track!

Trains would need to pass at places East of Croxley station, but then if the line was double-track through and to the East of Cassiobridge station, trains could pass with impunity.


  • The Borders Railway looks to have too much single-track
  • The Barking Riverside Extension is being built with a double track.

Too much single-track is often regretted.

Why Four Trains Per Hour?

Four trains per hour (tph) is becoming a standard, as it encourages Turn-Up-And-Go behaviour from travellers.

It also fits well with keeping the four tph Metropolitan Line service to Watford station, as this could give a same platform interchange at Croxley station.

Would The New Track Be Electrified?

The only part of the route that is not electrified is the about three miles of new track between  the Watford Branch and the Watford DC Line.

All current electrification is either third-rail or to the London Underground standard. and any future electrification would probably be to the London Underground standard, so that S Stock can work the route.

I believe that the Class 710 trains will have a limited onboard energy storage capability, which could enable the trains to bridge the cap in the  electrification between Watford High Street and Croxley stations.

How much would not electrifying the new track save?

How Long Will A Journey Take From Amersham Or Aylesbury To Watford Junction?


  • Amersham to Croxley takes about 30 minutes, but it does involve a change to a bus.
  • The Overground takes three minutes between Watford Junction and Watford High Street stations.
  • Chiltern Railways achieve a twelve minute time between Amersham and Rickmansworth.

I suspect that a modern train like one of London Overground’s Class 378 trains could do the journey in a few minutes under half-an-hour.

As Amersham to Aylesbury takes about sixteen minutes, that looks like a trip between Aylesbury and Watford Junction would take about forty-five minutes.

Amersham Or Aylesbury?

My original plan used Amersham, as it has a turnback facility.

But Aylesbury looks to have space as this Google Map shows.

It should also be noted that the forty-five minute journey time between Aylesbury and Watford Junction stations, would give a two hour round trip, with relaxed fifteen minute turnround times.

This would allow time to top-up the batteries.

What Class Of Train Could Be Used?

Four-car Class 378 trains or the new Class 710 trains would be ideal. As the Class 378 train is out of production, it would have to be Class 710 trains or something similar from Bombardier. But other manufacturers might have a suitable train.

Battery power would be required, but that is becoming a standard option on metro trains like these.

How Many Trains Would Be Needed?

If the trains could do an Out-and-Back journey in an hour, then four trains would be needed to provide a four tph service.

A two-hour time would need eight trains.

Will The Link Have Any Other Services?

I have seen to plans to use the line for any other passenger or freight services.

Will There Be Infrastructure Issues At Existing Stations?

As all of the trains, I’ve mentioned and the London Underground S Stock trains, share platforms all over North West London, the answer is probably no, with the exception of a few minor adjustments to signs and platforms.

Croxley Station

Croxley station would be unchanged.

But in addition to the 4 tph between Baker Street and Watford, there would be 4 tph between Watford Junction and Amersham.

Platform 1 would handle.

  • Baker Street to Watford
  • Amersham to Watford Junction

Platform 2 would handle.

  • Watford to Baker Street
  • Watford Junction to Amersham

This would mean that if the trains alternated, the maximum wait for a connection would be about 7.5 minutes.

What I feel would be the two most common connections, would just involve a wait on the same platform.

I suspect that those, who timetable trains, would come up with a very passenger-friendly solution.

Watford Station

A property developer once told me, that the most profitable developments, are those where a railway station is involved.

The Platforms At Watford Station

So would the development of the extension involve a rebuild of Watford station to provide the following?

  • A modern future-proofed station, with all the capacity that might be needed in the next forty years or so.
  • Appropriate housing or commercial development on top of the new station.
  • Sensible amounts of parking for travellers.

With four tph to and from London in the basement, it would surely be a profitable development.

Watford Junction Station

Watford Junction station has four bay platforms 1-4, that handle the three tph service on the Watford DC Line.

At stations like Clapham Junction, Crystal Palace, Dalston Junction, Highbury and Islington and New Cross, single platforms handle four tph with ease for London Overground services.

This means that handling four tph to Amersham in addition to current services would not be difficult.

The only work, that I think should be done, is make sure that these platforms are long enough to take two of the future Class 710 trains working as an eight-car train.

There could even be two platforms left for Bakerloo Line services, if it were to be decided, that these services would go to Watford Junction.

Elton John Plays Vicarage Road Stadium

This or some football matches at Vicarage Road Stadium, would be the biggest test of the Link.

Note the following.

  • Some stations  like Watford High Street can already handle longer trains than the hundred metre long, five-car Class 378 trains they currently do.
  • Some stations like Croxley can handle the 133 metre long S Stock trains used on the Metropolitan Line.

So to future-proof the Link for massive one-off events would it be sensible to make the platforms long enough for eight-car trains or two Class 710 trains working as a pair?


The benefits of this approach are as follows.

  • Watford station keeps its current service to London.
  • Watford gets a four tph link across the South of the town, serving the Shopping Centre, the Hospital and the Stadium.
  • Amersham or Aylesbury to Croxley stations get a link to the West Coast Main Line.
  • It could be built as a single track line without electrification.
  • Trains to run the services could be more easily available.
  • Simple island platform-based stations could be built at Cassiobridge and Vicarage Road.

In addition, Chiltern Railways, London Midland, London Overground and Underground, all gain a feeder railway bringing travellers to their services to and from London.

Cost Savings


  1. Transport for London needs cost savings on this project.
  2. Redevelopment of Watford station as a station with oversite development could raise a lot of money.
  3. The Croxley Link could be built as a single-track link without electrification and run initially using battery-electric trains.

I also feel, that building the line this way would deliver it earlier, thus improving cash-flow.

The simple link would need at the minimum.

  • A single- or double-track railway without electrification between Croxley and Watford High Street stations.
  • Two stations with island platforms at Cassiobridge and Vicarage Road
  • A viaduct to connect Cassiobridge station to the Watford Branch.
  • Some Class 710 trains or similar.

If skates were worn, the link could probably open in 2025.

December 20, 2019 Posted by | Transport | , , , , , , , | 1 Comment

A Trip To Aylesbury Vale Parkway Station

Aylesbury Vale Parkway station is one of Chiltern Railway’s termini in Buckinghamshire.

It is on the London to Aylesbury Line with services to Marylebone via Amersham, with a journey time of five minutes over the hour.

Plans also exist for the station to be calling point on the proposed service between Marylebone and Milton Keynes. The plans for the station in Wikipedia say this.

East West Rail plans to extend passenger services northwards to Bletchley and Milton Keynes by 2019 using parts of the former Varsity Line. The platform has been built to accommodate a second track if ever implemented, which would create an island platform. At present trains (currently run only as specials onBank Holidays) between Aylesbury and Quainton Road cannot serve Aylesbury Vale as there is no platform on the through route.

The track between Aylesbury and the new station was upgraded to continuous welded rail with a maximum line speed for DMU passenger trains of 60 mph (97 km/h). It is proposed that when services are extended to the north, trains will run via High Wycombe and not Amersham. Trains currently serving the station will thereafter terminate at Aylesbury.

These are some pictures I took of the station.

It is just a simple affair with a bus stand, car parks and the usual facilities, that appears will be soon surrounded by houses.

Chiltern Railways And Electrification

Before discussing how services will link up and down the London to Aylesbury Line, I will look at Chiltern Railways and electrification.

Under Developments and Announcements in the Wikipedia Entry for the East West Rail Link, this is said.

On 10 January 2013 Network Rail announced its intention to construct the western section between Bedford and Oxford, Aylesbury and Milton Keynes, as part of their five-year strategic business plan (2014–2019). The target date for train services to be operational on this section is December 2017. Electrification of the line between Oxford and Bedford was also included in the budget and target completion date was March 2017.

So electrification of the East West Rail Link is included in the project, even if the dates in the announcement are very much out of date now.

Given the following facts about the Chiltern Main Line, I believe it is likely that at some point, everybody will look seriously at providing electric trains from Marylebone to Birmingham Snow Hill station.

  • The line has a close relationship with the East West Rail Link and other electrified or soon-to-be electrified lines.
  • Chiltern finds it difficult to acquire more diesel-powered trains to fulfil their ambitions.
  • Chiltern would like to run faster, larger, more efficient and greener electric multiple units.

Under Electrification in the Wikipedia entry for Chiltern Railways, this is said.

No section of the line is electrified, but in 2010 the chairman of Chiltern Railways, Adrian Shooter, indicated that electrification is being considered, though not in the immediate future. He added: “We could do some very interesting things with high-acceleration EMUs and possibly some further infrastructure work.

At some time in the next ten years, we’ll probably see electric trains between Marylebone and Birmingham Snow Hill.

But there will not necessarily be full electrification, as I believe IPEMU technology will change the way electrification is carried out.

Consider as well that the Chiltern Main Line is just one hundred and eighty kilometres long and the current maximum range of an IPEMU is being quoted as about sixty miles or just under a hundred kilometres, so with the following electrification.

  • Marylebone and for perhaps twenty miles or so to handle local metro services.
  • Birmingham Snow Hill, Birmingham Moor Street and the Snow Hill Lines, where there are local metro services.
  • Banbury to Leamington Spa and other places, so that freight trains powered by bi-mode Class 88 locomotives,  could use the line efficiently.

The Local lines from Marylebone and the Snow Hill Lines would be electrified using the techniques in A Modern Electrified Metro Network Using IPEMU Technology

IPEMUs would be able to run the full length of the line without the need for full electrification in an environmentally-sensitive area, inhabited by touchy people.

Northward To The East West Rail Link And Milton Keynes

Northward from Aylesbury Vale Parkway station, the Wikipedia entry for East West Rail Link, says that the line will be single track and allow 90 mph working. But as my pictures and a quick gander on Google Maps show, there is quite a bit of space available around the current single track. So as the East West Rail Link seems to be being designed as a double-track 100 mph railway, with full electrification, I think there are three possible options between the East West Rail Link and Aylesbury Vale Parkway and Aylesbury stations.

  • Double-track 100 mph with electrification.
  • Single-track 90 mph with electrification.
  • Single-track 90 mph without electrification.

I think the line will be built with some form of electrification, so that electric trains can run from Aylesbury to Milton Keynes.

The line is also used by some freight trains, so double-track might be a good idea.

Aylesbury To London Via Amersham

Returning from Aylesbury today, I was surprised to see that the train ran from Amersham to Harrow-on-the-Hill on the same tracks as the Metropolitan Line. In fact for sixteen  of the thirty-nine miles of the line from Marylebone to Aylesbury Vale Parkway, the line has full London Underground electrification.

Amersham to Aylesbury is about fifteen miles, with the distance between the two Aylesbury station being four miles, which means that Harrow-on-the-Hill to Marylebone is just a few miles.

So if an IPEMU could use the London Underground’s rail-based electrification, starting at Milton Keynes the train would easily arrive at Harrow-on-the-Hill with a full battery, that would take the train to Marylebone and back.

I don’t believe that the technical problems of an IPEMU starting at any station between Aylesbury and Milton Keynes and going to Marylebone and back are insurmountable.

Aylesbury To London Via High Wycombe

This uses the single-track Aylesbury to Princes Risborough Line, which is about a dozen miles long, before running to Marylebone along the Chiltern Main Line, which is another forty miles or so.

So some electrification will be needed.

According to Wikipedia, Chiltern have various plans to improve their network.

  • The restoration of the quadruple track between South Ruislip (Northolt Junction) and West Ruislip, allowing trains to call at both stations without blocking the line. Triple track currently exists at West Ruislip, with the up platform loop still in situ, and at South Ruislip, with the Down Main through line also in situ. This would involve the reconstruction of the new down platform at West Ruislip, and the reconstruction of the up platform at South Ruislip. This ‘Chiltern Metro’ service was not programmed into the last round of franchising agreements.
  • Restoration of fast through lines at Beaconsfield as part of a longer-term aspiration for a 90-minute journey time between London and Birmingham
  • Double-track the line from Princes Risborough to Aylesbury.
  • New Chiltern Metro Service that would operate 4+tph for Wembley Stadium, Sudbury & Harrow Road, Sudbury Hill Harrow, Northolt Park, South Ruislip and West Ruislip. This would require a reversing facility at West Ruislip, passing loops at Sudbury Hill Harrow, and a passing loop at Wembley Stadium (part of the old down fast line is in use as a central reversing siding, for stock movements and additionally for 8-car football shuttles to convey passengers to the stadium for events)

Some would also fit well with adding electrification, so I think that enough electrification can be added to allow an IPEMU to go from Aylesbury to Marylebone.

Oxford To London

Given that there will be electrification between Oxford and Bicester Village stations courtesy of the East West Rail Link, IPEMUs could start at Oxford and reach Princes Risborough, from where they used the same methods as Aylesbury and Birmingham services to get to London.

This article on the BBC, which is entitled Cowley line passenger train service planned for Oxford, says this.

Chiltern Railways has revealed plans for a passenger service to run on the Cowley branch in Oxfordshire.

The line, currently only used for freight, would see two new stations on the route at Oxford Science Park and Oxford Business Park.

So if this service goes to London, it would certainly be another job for an IPEMU.

Watford Junction To Amersham And Aylesbury

The Croxley Rail Link has been designed so it can have a link to Amersham. Wikipedia says this about the link.

A further proposal is to use the existing but seldom-used Metropolitan line chord which allows trains to run from Watford towards Amersham via Rickmansworth. In conjunction with the Croxley Rail Link, this route would allow direct services between Watford Junction and Amersham, thus improving local public transport in Hertfordshire and Buckinghamshire.

These are pictures I took, as the train passed the  junction of the branch line to Watford.

It would certainly be a new use for a substantial piece of infrastructure, but would it do much more than link Amersham to Watford Junction.

Chiltern Trains could run an IPEMU from Watford Junction to Aylesbury Vale Parkway calling at all stations, but as passengers could also get to Aylesbury from Milton Keynes, I wonder if it would be well used.


April 6, 2016 Posted by | Transport | , , , , , , , , | Leave a comment