Radyr Station
Radyr station is a junction station on the Cardiff Valley Lines.
These pictures show the station.
It certainly has a massive modern step-free bridge.
This Google Map shows the station.
Note.
- The platforms are long.
- South of the station, the tracks split into two, with the City Line going in a more Southerly direction.
Currently services at the station are as follows in trains per hour (tph).
- Two tph North to Aberdare
- Two tph North to Merthyr Tydfil
- Two tph North to Treherbert
- Six tph South to Cardiff Queen Street and Cardiff Central stations via Cathays.
- Two tph between Radyr and Coryton stations via the City Line, and Cardiff Central and Cardiff Queen Street stations.
In 2023 the service will be upgraded.
- Four tph North to Aberdare
- Four tph North to Merthyr Tydfil
- Four tph North to Treherbert
- Six tph South to Cardiff Queen Street and The Flourish stations via Cathays.
- Two tph South to Cardiff Queen Street and The Cardiff Central stations via Cathays and back via the City Line.
- Two tph South to Cardiff Queen Street and The Cardiff Central stations via the City Line and back via Cathays.
- Two tph South to Cardiff Queen Street via Cathays.
All services will be run by new Stadler Citylink Metro Vehicles.
Note.
- No services will start at Radyr station.
- No station will get a less frequent service.
- There will be a doubling of services through Radyr station.
- There will be level access between platform and vehicles at all stations.
- If required the new vehicles can run in pairs to increase capacity.
I also suspect this is only the start and that capacity will be increased on some lines.
Train Depot In Taffs Well, While Newport Factory Named As Preferred Bidder For New Diesel Trains
The title of this post, is the same as that of this article on Walesonline.
The interesting part is the holistic thinking, where a new depot is to be built at Taff’s Well, where the station is also to be modernised, with the addition of a Park-and-Ride.
Taff’s Well station is a very outdated affair, as these pictures show.
Note.
- The station could certainly do with a new step-free bridge.
- The train frequency is also being raised from six to twelve trains per hour (tph)
- Six tph will go to The Flourish.
- There will also be a new two tph service on the City Line.
- All trains will be new Stadler Citylink Metro Vehicles.
That Park-and-Ride will certainly be needed.
As Taff’s Well station will be at the heart of the tram-train network, it is most certainly a good place for the depot.
The article also says that enhanced stabling facilities will be built at Treherbert and Rhymney stations.
Enhancements At Rhymney
Rhymney station is the terminal of the Rhymney Line.
These are my pictures of the station.
This Google Map gives an aerial view.
In addition to the enhanced stabling, the station will also be upgraded to accommodate more and longer Tri-Mode Stadler Flirts.
There’s certainly a lot of space for the stabling.
Enhancements at Treherbert
Treherbert station is the terminal of the Rhondda Line.
I took these pictures of the station in 2014.
This Google Map shows an gives view.
There certainly would appear to be space for the enhanced stabling.
Caerphilly Station
Caerphilly station is an important one on the South Wales Metro.
The current service is a four trains per hour (tph) service to Cardiff Queen Street and Cardiff Central stations. Some trains travel through to Penarth station
In 2023, the service will be upgraded.
- Two tph between Barry Island and Rhymney stations via Cardiff Central.
- Two tph between Bridgend and Rhymney stations via Cardiff Central and Rhoose Airport
- Two tph between Penarth and Caerphilly stations via Cardiff Central.
In 2023, the service will be three minutes quicker to and from Cardiff.
In addition, note the following about Caerphilly station.
- The station is on the Rhymney Line, which will be worked by Tri-Mode Stadler Flirts.
- The station lies just to the North of the Caerphilly Tunnel, which is not being electrified and trains are expected to transit using battery power.
- The station has a bay platform.
- The station appears to be a hub for buses.
This Google Map shows the station.
Note.
- The long bay platform on the North side of the station. It may be long enough to accommodate two of the Tri-Mode Stradler Flirts, which are 65/80 metres long. This means that the bay platform could be very valuable for service recovery.
- The station serves as a Park-and-Ride.
- Three structures cross the track, which from the left are the old station buildings, the station footbridge and a footbridge independent from the station.
- Looking at the track layout on the Eastern approach to the station, the cross-overs are within fifty metres of the platform end.
These pictures show the station.
These are my thoughts on various issues.
Electrification Under The Bridges And The Old Buildings
I think there would be serious issues with standards for electrification at this station.
The three structures will have to be handled in the way I described in How Can Discontinuous Electrification Be Handled?
The Old Station Building
The old station building is integral with a road bridge and would be a costly and very disruptive operation to replace.
So if the structure will safely last a hundred years or so and the wires can be squeezed underneath using discontinuous methods, everybody wins.
The Easternmost Footbridge
The Easternmost bridge at the far end of the platforms looks to be a fairly recent structure and is independent of the station, as it just gives pedestrians a route across the railway. It might even have been built, when the bay platform was built a few years ago.
The Station Footbridge
So that leaves the elderly footbridge, which probably dates from 1871, when the station was moved to its present position.
It is the main way that passengers cross the line and given that Caerphilly station has nearly a million passengers a year, it would be classed by disabled activists as a disgrace.
A few stations up the line, lifts were added to the footbridge at Ystrad Mynach station, in conjunction with other works. Wikipedia says this.
In 2014, the station underwent a £1.6 million refurbishment with new ticket machines, waiting areas and ticket office, with disabled toilet being installed in addition to major work carried out on the footbridge with lifts being installed to improve accessibility.
Surely some of the money saved on electrification could be spent on improving access?
Electrification Between The Structures
25 KVAC wires have to be several metres away from any staff and passengers.
The Northbound Platform 3 is wide and if the overhead wire can be suspended high enough, I suspect that the latest regulations can be met.
The Southbound Platform 2 is narrower and the platform has a low roof, which might mean electrification is trickier.
But if as I suspect, battery power and gravity will be used to power the trains on the downhill track, then there could be a case for leaving the downhill track without wires.
That could save half the costs on some sections of the route.
Electrification Of The Crossover
On a railway with full electrification all crossovers must be electrified..
But on the Rhymney Line, all the trains will be Swiss all-purpose trains, that can work on all power sources, probably including cuckoo-clock motors.
So imagine a Tri-Mode Stadler Flirt arriving from Penarth, which will be turning back in the bay platform at Caerphilly.
- It would use the electrification between the unelectrified Caerphilly Tunnel to just before the crossover to come up the hill and probably add some charge to the batteries, that have been depleted in the run through the mile-long tunnel.
- \\\the train would probably rate at a signal just before the crossover, until told to proceed by the signalling system.
- The pantograph will be dropped and the train switched to battery or diesel power.
- When giving the green by the signal, the train would move into the bay platform.
All done efficiently and safely without any electrification, which would not be installed on the crossover or in the bay platform.
Train Failure In The Caerphilly Tunnel
There will have to be a plan for handling train failures in the tunnel. I suspect that as Switzerland has lots of railways in the mountains, some with extensive tunnels, that the Swiss have pretty good methods for dealing with failures.
One Train Rescues Another
Trains are generally designed, so that a second train can rescue a failed train of the same class or even a similar type. This makes good sense, as a train operator generally has several trains of the same type and their Thunderbird locomotive may be working miles away.
I’m sure that the Tri-Mode Stadler Flirts will have this capability.
Rescuing A Train Going Downhill
If a train should fail in the Caerphilly tunnel on the downhill track, a second train would probably couple up and shepherd the train slowly down the hill to the depot at Canton.
Rescuing A Train Going Uphill
If a train should fail in the Caerphilly tunnel on the downhill track, a second train would probably couple up and push the stricken train into the bay platform at Caerphilly station.
Conclusion
The more I look at the South Wales Metro, it has been designed in an holistic manner with routes, tracks, electrification, stations and trains all designed to work together.
The Flourish Station Is The Focus Of The South Wales Metro
On my visit, I walked for an hour in the Cardiff Bay area. Wikipedia says this.
Cardiff Bay is the area of water created by the Cardiff Barrage in south Cardiff, the capital of Wales. It is also the name commonly given to the surrounding areas of the city. According to Cardiff Council, the creation of Cardiff Bay is now widely regarded as one of the most successful regeneration projects in the United Kingdom.
These picture were taken as I walked.
I’m not exactly sure, where the new station at The Flourish will be placed.
This document on the KeolisAmey web site details their plans for the new Wales and Borders Franchise.
Look at this image that I clipped for the document.
And this Google Map of the area.
It looks like The Flourish station will go by the triangle of roads to the right of the Merchant Place building.
It will really bring the South Wales Metro to the heart of the action.
Battery Tram-Trains To The Flourish
The Cardiff Bay Line links to Cardiff Queen Street station and is only two kilometres long.
This distance should be well within the capabilities of a battery electric tram or train.
So will the Cardiff Bay Line be left totally without wires from Cardiff Queen Street station?
If it was, this would reduce costs and visual intrusion.
In Stadler Citylink Metro Vehicles, I estimated that if a tram-train had a 50 kWh battery, this would have a range of five miles, which would take the vehicle from Queen Street to The Flourish and back.
If necessary, the uphill line to Queen Street station could be electrified.
But there would certainly be no wires South of Cardiff Bay station.
The Proposed Service To The Flourish
Aberdare, Merthyr Tydfil and Treherbert will have a four tph service to Cardiff Queen Street station and a two tph service to The Flourish station.
This means there will be six tph between Cardiff Queen Street and The Flourish stations. Or a tram-train every ten minutes!
There will also be a new station at Loudon Square, between Cardiff Queen Street and Cardiff Bay stations.
From figures in the KeolisAmey document, if appears that Cardiff Queen Street to The Flourish will take four minutes.
Conclusion
This will certainly be a World Class station fit for the area it serves.
Between Cardiff Queen Street And Cardiff Bay Stations
Cardiff Queen Street and Cardiff Bay stations are the two termini of the Butetown Branch Line.
These pictures show my trip from Cardiff Queen Street to Cardiff Bay and the trip back.
Note.
- Cardiff Bay station is a Grade II* Listed Building.
- With passenger usage of nearly a million and a quarter last year, is it the busiest single-platform station in the UK?
- It was certainly busy yesterday.
- The access for the number of passengers is inadequate.
- After removing the foliage, there must be room to add a second track, between the two stations.
This Google Map shows where the railway lines cross.
Note.
- Cardiff Central station is to the West.
- Cardiff Queen Street station is to the North.
- Cardiff Bay station is to the South.
Does the map show that running a service between Cardiff Central and Cardiff Bay stations would be difficult?
Loudon Square Station
The planned Loudon Square Station would appear to be 300-400 metres North of Cardiff Bay station.
Capacity Increase
When the current Class 150 trains with a frequency of five trains per hour are replaced by new Stadler Citylink Metro Vehicles with a frequency of six trains per hour, this will give an approximate doubling of capacity.
And there is always the option of using the Stadler Citylink Metro Vehicles in pairs!
Cardiff Queen Street Station
Cardiff Queen Street station is the first station to be refurbished for the proposed South Wales Metro.
Note.
- The station is fully step-free.
- The platforms are wide, which helps interchange or waiting for your destination. See Canada Water on the Overground and St. Pancras on Thameslink.
- Currently, to get to Cardiff Bay station, you need to catch a five trains per hour (tph) shuttle train from Platform 1.
The service pattern is fairly-straight-forward, with the following lines passing though the station from South to North.
- 2 tph – Coryton Line between Radyr and Coryton stations via Cardiff Central.
- 2 tph – Cynon Line between Barry Island and Aberdare stations via Cardiff Central.
- 2 tph – Rhondda Line between Cardiff Central and Treherbert stations.
- 3 tph – Rhymney Line between Cardiff Central and Bargoed stations.
- 1 tph – Rhymney Line between Penarth and Rhymney stations via Cardiff Central.
- 2 tph – Taff Line between Cardiff Central and Merthyr Tydfil stations.
It is said, that to build anything, you need good foundations.
These services through Cardiff Queen Street station, seem to be a good foundation for the South Wales Metro.
The current proposed services through the station after the Metro is completed are.
- 2 tph – Coryton Line between Penarth and Coryton stations via Cardiff Central – Tri-Mode Stadler Flirts
- 2 tph – Cynon Line between The Flourish and Aberdare stations.. – Stadler Citylink Metro Vehicles
- 2 tph – Rhondda Line between Cardiff Queen Street and Treherbert stations – Stadler Citylink Metro Vehicles
- 2 tph – Rhondda Line between The Flourish and Treherbert stations – Stadler Citylink Metro Vehicles
- 2 tph – Rhymney Line between Barry Island and Rhymney stations via Cardiff Central – Tri-Mode Stadler Floirts
- 2 tph – Rhymney Line between Bridgend and Rhymney stations via Cardiff Central – Tri-Mode Stadler Flirts
- 2 tph – Rhymney Line between Penarth and Caerphilly stations via Cardiff Central – Tri-Mode Stadler Flirts
- 2 tph – Taff Line between The Flourish and Merthyr Tydfil stations – Stadler Citylink Metro Vehicles
- 2 tph – Cynon and Taff Lines between Aberdate and Merthyr Tydfil stations via the City Line and Cardiff Central – Stadler Citylink Metro Vehicles.
Summarising services gives these figures.
- 6 tph – To and from The Flourish – Stadler Citylink Metro Vehicles
- 10 tph – To and from Cardiff Central – Tri-Mode Stadler Flirts
- 2 tph – To and from Cardiff Central – Stadler Citylink Metro Vehicles
This Google Map shows Cardiff Queen Street station.
Note.
- The bay platform, which is numbered 1, is in the South East corner of the station. is used for services to Cardiff Bay station.
- There is no North-facing bay platform.
- Northbound trains for Aberdare, Merthyr Tydfil and Treherbert share Platform 5.
- Northbound trains for Bargoed, Coryton and Rhymney share Platform 4.
- Sounthbound trains use Platforms 2 and 3.
I believe that this layout will be changed in the creation of the South Wales Metro.
In an ideal world passengers should have a same-platform or cross-platform interchange between services going in the same direction.
If services going in the same direction shared the same platform, this would meet sixteen tph using two platforms, as two tph will terminate at Cardiff Queen Street station.
Canada Water station on the East London Line of the London Underground in a couple of years will be handling twenty tph.
- The platforms are wide with escalators, lifts and stairs.
- Four Southern destinations and Two Northern destinations are served.
- All services are run by Class 378 trains.
- Access between train and platform is step free and wheel-chairs and buggies can be pushed across.
- The East London Line has modern signalling.
If Crossrail and Thameslink will be able to handle twenty-four tph with digital signalling, I believe a solution can be found so that sixteen tph can pass through Cardiff Queen Street station.
Having seen wide platforms in operation at stations like Canonbury, London Bridge and Whitechapel, I feel an ideal layout at Queen Street station would be to use Platform 3 for all Southbound services and Platform 4 for all Northbound services, with as wide a platform as possible in between.
Consider.
- Passengers from Rymney and Coryton needing to go to The Flourish, would get off the train and get a Citylink for The Flourish.
- Passengers between The Flourish and Cardiff Central would just have to walk across the platform at Queen Street station to change trains.
- Passengers needing a train to Rhoose Airport could choose to change at Queen Street station.
Most waits at Queen Street station would be in a few minutes.
Although, passengers would wait longer for Barry Island, Bridgend and Rhoose Airport.
There is still the problem about what to do with the two tph that from Treherbert that terminate at Queen Street station.
- They could use Platform 2 or 5.
- They could use a new bay platform in the North end of Pltform 3/4.
- They could go through Queen Street station to terminate at The Flourish
- They could go through Queen Street and Central stations to terminate elsewhere.
Option 1 would have problems.
- Every thirty minutes a Citylink would have to cross the busy lines to the North of Queen Street station.
- Passengers wouldn’t always use the same platform for the Rhondda Line.
- Passengers wouldn’t have an easy interchange at Queen Street station.
Option 2 would be better.
- The track layout would be similar.
- Rhondda Line passengers would only have the inconvenience of sometimes walking along the platform.
.Even if this option was not used to turn trains, I suspect it could be built, as it would also be useful for service recovery purposes.
I like Option 3, although it will have the following consequences.
- ,The Flourish would need to be able to handle eight tph on the two proposed platforms.
- Queen Street station would need to be able to handle eighteen tph in both directions.
I suspect that both problems are solvable.
The problem with Option 4 is where do you turn the two extra trains?
I suspect that the Citylink vehicles can only use the City Line after Cardiff Central.
Would it be a good idea or not to run four tph on this route?
I don’t know! But a personable young station man at Queen Street station, said that handling the football can be a problem.
So perhaps more trains going to Ninian Park station might be a good idea.
I write about it in detail in The South Wales Metro and Big Events.
Conclusion
Cardiff Queen Street station has the possibility to be a World Class Metro interchange.
KeolisAmey’s Plans For The Rhymney Line
This document on the KeolisAmey web site details their plans for the new Wales and Borders Franchise.
The Rhymney Line has the following characteristics.
- It runs between Cardiff Queen Street and Rhymney stations.
- Most of the line is double-track, with a short length of single-track from Tir-Phil station.
- There is the Coryton branch line to Coryton station.
- From Cardiff to Bargoed station, there are four trains per hour (tph)
- North of Bargoed, an hourly service generally operates.
- \from Cardiff to Coryton station, there are two tph.
- Some services, run through Cardiff to Penarth or Barry Island stations.
- Services take sixty-one minutes between Rhymney and Cardiff.
- Services take eighteen minutes between Coryton and Cardiff.
What improvements will be made to the Rhymney Line?
New Trains
From 2019, cascaded Class 170 trains will run services on the line.
In 2023, these trains will replaced by new Tri-Mode Stadler Flirts.
Current plans, don’t envisage any of the Stadler Citylink Metro Vehicles working the line. But I don’t see any reason why they can’t, if say Transport for Wales wanted to run a service from Cardiff Bay to Coryton or any other station.
It could be that their batteries don’t have enough capacity for the Caerphilly Tunnel.
New Stations
The KeolisAmey document, states that a new station will be built at Crwys Road.
I’ve also read somewhere that there may be a station on the Coryton Line to serve a major new hospital.
Improved Services
In 2023, the following services will be in place.
- From Cardiff to Rhymney station, there will be four tph.
- From Cardiff to Coryton station, there will be two tph.
- Services will take forty-eight minutes between Rhymney and Cardiff.
- Services will take twenty minutes between Coryton and Cardiff.
The Coryton service is slower because of the proposed new station.
Electrification
The line will be electrified using 25 KVAC.
- There is a short tunnel at Bargoed station.
- There is a mile-long tunnel at Caerphilly.
- There were quite a few footbridges across the tracks.
- The margins on either side of the track seem adequate on much of the route.
It looks to me, that electrification of the Rhymney Line cshuld be possible, provided the design is good.
The Tri-Mode Stadler Flirts will have batteries, which will have these purposes.
- Provide traction power for the trains, where there is no electrification.
- Capture the energy generated by the traction motors under braking.
- Ensure that power is always available for the train’s control, driver and passenger systems.
On the Rhymney Line, battery power will also be used to provide traction power in the mile-long Caerphilly Tunnel.
I have been told that although the tunnel will not be electrified, there will be an overhead rail for the pantograph in the tunnel, which will not be electrified.
This means that the pantograph doesn’t have to be raised and lowered, as the train goes up and down the hill, as there is a continuous overhead rail and line for the pantograph to use all the way.
I believe that when the train is coming down the hill, that gravity and the onboard battery will give sufficient power to bring the train safely down the hill.
So is there any point in electrifying the downhill path?
- The two terminals on the line; Rhymney and Coryton stations, are single platform stations on single-track lines, which will surely be electrified.
- If necessary batteries could be topped up before on the single track sections, before joining the double-rack line to Cardiff.
- There is very little if any freight or engineering trains on the line. But these will be diesel-hauled.
- After the modernisation, all the passenger trains will be the new electric trains with batteries and/or diesel engines.
- Diesel trains and locomotives could continue to work the lines as required.
I don’t think there is any operational reason for the downhill path to be electrified.
It would reduce costs in both construction and maintenance.
Stadler Citylink Metro Vehicles
This document on the KeolisAmey web site details their plans for the new Wales and Borders Franchise.
The Stadler Citylink Metro Vehicles in the KeolisAmey document. look very similar to Sheffield Supertram‘s Class 399 tram-trains, that are providing a tram service in Sheffield and will soon be running on the heavy rail network to Rotherham.
- The Citylink vehicles seat 88 with 150 standees.
- They can run using 750 VDC or 25 KVAC overhead electrification.
- The tram-trains are built by Stadler in Spain.
- According to a driver, that I spoke to in Sheffield, the tram-trains have a good hill climbing capability.
These pictures were taken of one of the Class 399 tram-trains operating in Sheffield.
The Keolis/Amey document gives more details on the tram-trains.
- Main power source 25kV overhead line but also operates from battery.
- Capacity of 257 with seats for 129.
- Capable of on-street line-of-sight ‘tramway’ operation.
- They can work in pairs.
I’ve known for some time, that Class 399 tram/trains had a battery.
but I thought it was probably for secondary purposes, like making sure the vehicle crossed the boundary, where the two voltages change.
So it looks like in Cardiff, battery power will be used for traction.
How Big Will The Batteries Need To Be?
Consider a Class 399 tram/train, working to and from Merthyr Tydfil.
- Wikipedia gives the weight of the vehicle as 66 tonnes.
- Rhymney has an altitude of 178 metres.
- I will assume 200 passengers at 90 Kg. each, which gives a weight of 12 tonnes.
This means that the train has a potential energy of 41 kWh at Merthyr Tydfil station.
On the way down the hill from Merthyr Tydfil the regenerative braking will convert this potential energy into electricity, which will be stored in the battery.
I would reckon that a battery of about 50 kWh would be an ideal size, but would it be big enough to take the Stadler Citylink Metro Vehicles from Cardiff Queen Street station to The Flourish and back?
That journey is probably about 1.5 miles each way.
How Far Would A Full 50 kWh Battery Take A Stadler Citylink Metro Vehicle?
In an article in the October 2017 Edition of Modern Railways, which is entitled Celling England By The Pound, Ian Walmsley says this in relation to trains running on the Uckfield Branch, which probably has a terrain not much different to the lines to the South and West of Cardiff.
A modern EMU needs between 3 and 5 kWh per vehicle mile for this sort of service.
This would mean that a 50 kWh battery would take a three-car Stadler Citylink Metro Vehicle up to five miles, if the usage of the lighter-weight tram-train was at the lower end of the quoted range.
The battery would certainly take a Stadler Citylink Metro Vehicle from Cardiff Queen Street station to The Flourish and back.
Conclusion
As with the Tri-Mode Stadler Flirts, the Stadler Citylink Metro Vehicle with a battery, looks a very interesting concept.
- Most of the energy is provided by the 25 KVAC electrification, which would power the tram-train up the hill.
- Coming down the hill, the battery would be recharged using the regenerative braking.
- Battery power would used to take the tram-train on routes without electrification to The Flourish station.
Energy efficiency would be high.
Stadler Flirt DEMUs
Over a thousand Stadler Flirts have been sold to operators around the world. Most have been or will be built in Switzerland.
Greater Anglia
The first fleet in the UK, comprise fourteen three-car and twenty-four four-car Class 755 trains for Greater Anglia.
This visualisation shows a Class 755 train in Greater Anglia livery, running through the typical flat lands of East Anglia.
These trains will enter service next year.
- They are 100 mph trains.
- They can run on 25 KVAC overhead electrification.
- They have a diesel power-pack, which can have up to four Deutz diesel engines, for running on lines without electrification.
- The three-car trains have two diesel engines and the four-car trains have four engines.
- They can change power source at line speed.
- Length is easily changed, by adding or removing cars.
- Three-car Flirts have 166 seats and four-car Flirts have 224 seats.
- They are designed to handle two-hour plus journeys, like Lowestoft to London for Greater Anglia.
I suspect they are fairly powerful trains and I wrote about this in Greater Anglia’s Class 755 Trains Seem To Have Bags Of Grunt.
Comparing the trains with a Class 170 train, I said this.
But the four-car Class 755/4 trains have fifty percent more power per car, than the Class 170 train, so these will be no sedate rural trundlers.
I’m certain, that their performance, will allow them to mix it on the Great Eastern Main Line with the London-Ipswich-Norwich expresses.
KeolisAmey Wales
From the pictures, the trains, that will be delivered to KeolisAmey Wales, look very much like the trains, that have been ordered by Greater Anglia.
The trains will operate services between Cardiff and Ebbw Vale, Maesteg and extending to Severn Tunnel Junction and beyond.
I would assume that the trains will use diesel, where there is no electrification. One current service goes between Maesteg and Cheltenham Spa stations. On the South Wales Main Line between Cardiff and Seven Tunnel Junction, the trains would use the 25 KVAC overhead wires, but at both ends of the route, they would use diesel.
One great advantage of bi-mode trains like these Flirts, is that as more electrification is added, they can take advantage.
I’m certain, that their performance, will allow them to mix it on the South Wales Main Line with the London-Newport-Cardiff-Swansea expresses.
Aosta Valley
A European version of the train will start to operate soon in the Aosta Valley in Italy, so when the trains for Wales are delivered, there will be lots of operational experience. Especially with climbing steep hills!
Norway
This article on the Railway Gazette is entitled Bi-Modes In Norway’s Next Flirt Order.
The bi-modes will be used around Trondheim, on routes without elewctrification.
What does Norway have a lot of? Mountains!
How Can Discontinuous Electrification Be Handled?
On the proposed South Wales Metro, it is proposed to use discontinuous electrification to avoid rebuilding a lot of bridges and other structures.
This document on the KeolisAmey web site details their plans for the new Wales and Borders Franchise.
The document states this about the electrification.
Discontinuous overhead line electrification to 25 KVAC with permanently earthed sections around restricted structures, saving 55 interventions e.g. rebuilding bridges/no need for wire in Caerphilly tunnel.
So how are these interventions avoided?
The Karlsruhe Solution
On the Karlsruhe Stadbahn, similar Citylink vehicles to those proposed for Cardiff need to work on both the main line 15 KVAC used in Germany and the 750 VDC used by Karlsruhe trams.
To isolate the two voltages, a ceramic rod is placed in the catenary. The vehicle’s pantograph just rides across the voltage boundary and the vehicle’s electrical system uses whatever voltage is present.
Bridges On The South Wales Metro
These pictures show some of the types of bridges on the Cardiff Valleys Lines.
They are a real assortment.
- Some station footbridges from the Victorian era with nice castings and decoration, but no much-needed step-free access.
- Some quality brick and stone arch bridges.
- British Rail-era steel bridges, with no architectural merit
- Some modern road bridges in steel and concrete.
I also saw sizeable pipelines over the railway, which would need to be raised.
The greatest number were simple steel bridges like the one at Caerphilly station, designed to get pedestrians and cyclists, who were not using the railway, from one side of the tracks to the other.
I suspect the simplest way would be to erect two standard gantries at a safe distance of a few metres either side of the structure.
Between the two gantries would be an conductor, like this one. that I photographed in the Berlin Hauphtbahnhof.
It would be earthed, so that it offered no danger to life. There could even be extra supports under the bridge.
At each end, it would be connected to the 25 KVAC using a ceramic rod or other insulating device.
The vehicle’s pantograph would then ride from one side of the bridge to the other on its own track without being lowered.
Anything electrified at 25 KVAC would be kept at a very safe distance from the bridge.
In the earthed section, when the vehicle would be receiving no power, the vehicle would automatically switch to battery power. There would be no driver action required, except to monitor it was all working as it should.
As on the South Wales Metro, it appears that all vehicles using the lines proposed to be electrified will have their own onboard batteries, there shouldn’t be any problem.
In some ways, this discontinuous operation is a bit like using your laptop connected to the mains. When say the cleaner pulls out the plug to put in the vacuum cleaner, your laptop switches automatically to the battery.
The Caerphilly Tunnel
The Caerphilly tunnel is over a mile long. This picture shows the tunnel entrance.
It would probably be possible to electrify using a rail in the roof, but why bother if the trains running through the tunnel could go from one end to the other on their own battery power?
Trains could lower the pantograph before entry and then raise it again, when under the electrification at the other end.
This could be performed automatically using a GPS-based system.
I have also had an e-mail, which said this.
As I understand Caerphilly will have a natural bar in it but be much closer to the train roof than would be allowed with a live one.
Now there’s an idea!
A composite or earthed metal rail would be fixed to the roof of the tunnel, so that the pantograph could run smoothly from one electrified section on one side of the tunnel to the electrification on the other side, using battery power all the way.
Cost Savings
In Novel Solution Cuts Cardiff Bridge Wiring Cost, I talked about another method applied in South Wales to avoid rebuilding a bridge.
At this bridge, traditional electrification methods were used, but the need to demolish the bridge was avoided by using advanced insulation and protection measures.
This was my final statement.
Network Rail reckon that the solution will save about £10 million on this bridge alone, as it avoids the need for an expensive rebuild of the bridge.
The savings on this bridge will be higher as it is a large bridge over several tracks, but even saving a million on each bridge in the South Wales Metro is £55 million, which will probably be enough to build much of the infrastructure to extend to The Flourish, which would appear to not need expensive viaducts or electrification.
Should Downhill Tracks Be Left Without Electrification?
I think this may be possible on the South Wales Metro, as vehicles coming down the hills could use gravity and small amounts of battery power.
Regenerative braking would also be continuously charging the batteries.
It would certainly be simpler, than having to constantly swap between overhead and battery power on the descent, where the electrification was discontinuous.
As the lines are going to have a more intensive service, there will be additions of a second track in places to allow trains to pass.
Any electrification that could be removed from the project would be beneficial in terms of building and operational costs.
Other Routes
This post has used the South Wales Metro as an example, but I don’t see any reason, why the discontinous method and that used on the Cardiff Bridge can’t be applied to other bridges and structures over the lines on other routes in the country.
I suspect, that if they’d been used on the Gospel Oak to Barking Line, electric trains would have been running months ago!
Conclusion
Look what you get with thinking, when you have a Bonfire of the Boxes!
The Anonymous Widower 