The Anonymous Widower

Uckfield Third Rail Is NR Priority

The title of this post, is the same as that of an article in the April 2022 Edition of Modern Railways.

This is the first two paragraphs.

Electrification of the line between Hurst Green and Uckfield in East Sussex and the remodelling of East Croydon are the top Network Rail investment priorities south of the river, according to Southern Region Managing Director John Halsall. He told Modern Railways that third rail is now the preferred option for the Uckfield Line, as it would allow the route to use the pool of third-rail EMUs in the area. This is in preference to the plan involving overhead electrification and use of dual-voltage units put forward by then-Network Rail director Chris Gibb in his 2017 report (p66, September 2017 issue).

NR has put forward options for mitigating the safety risk involved with the third-rail system, including switching off the power in station areas when no trains are present and section isolation systems to protect track workers.

The Office of Road and Rail hasn’t given Network Rail’s scheme the OK yet, but as an Electrical Engineer, I believe that a safe system is possible.

Making Charging Safe At Greenford

This article on Ian Visits is entitled Ex-London Underground Trains To Be Tested On The Greenford Branch Line.

The article describes how despite using London Underground’s four-rail electrification, it will be possible with the right interlocks and systems to make such a system safe.

As Vivarail’s system is to be installed, it must already agree with all the Health and Safety rules.

A Safe System On The Uckfield Branch

Consider.

• The unelectrified section of the Uckfield Branch is twenty-five miles long.
• There are seven intermediate stations, with the longest section between any two stations under five miles.
• Trains stop in each station on the route.
• Trains appear to have a dwell time of about a minute in each station.
• A ten-car pair of Class 707 trains would be 203.2 metres long.
• All platforms have been lengthened for ten-car trains.
• A battery-electric train running along unelectrified track, is no more dangerous than a diesel train.

This picture shows some typical third-rail electrification at Kidbrooke station in South East London.

Note.

1. The electrified rails are between the tracks.
2. Gaps are possible to isolate sections of tracks.
3. The third-rail is tapered, so that the third-rail shoes on the train can connect and disconnect easily.

Suppose you have a third-rail electric train with a range of say seven or eight miles on batteries.

Would it be possible to devise a safe electrified railway using this train and standard third-rail electrification with some safety modifications?

• The track in each station would be electrified in the normal way with the third-rail away from the platform.
• The length of electrification in each station would be  a few metres shorter than the length of the ten-car pair of Class 707 trains.
• This would mean that the train would completely cover the electrification, when it stopped in the station.
• The third-rail electrification would only be switched on, when a train is stopped in the station and the right interlocks are engaged.
• Even if a passenger fell onto the tracks, they would probably be safe, unless they crawled through the wheels to the centre of the tracks.
• There would be no electrification between the stations, which would protect track workers and trespassers.

I believe that a safe system can be devised.

A train going through a station would do the following.

• Slowing down, the train would use regenerative braking, that helped to charge the batteries
• The train would stop in a station, so that it connected with and covered the third-rail.
• When the charging system recognised that a train was connected, it would start to charge the batteries.
• When all passengers had unloaded and loaded and the train was ready, the driver would stop the charging process.
• The train would move to the next station on battery power.
• Safety interlocks would stop the charging under various unsafe circumstances.

I believe that Siemens could have developed a charging system like this for their Class 707 trains, as some of their other trains of a similar vintage to the Class 707 trains already offer battery options.

A Stepping Stone Approach

On the unelectrified section between Hurst Green Junction and Uckfield, there are the following stations.

• Edenbridge Town – two platforms
• Hever – two platforms
• Cowden – single bi-directional platform – 7.9 miles South of Hurst Green Junction.
• Ashurst – two platforms
• Eridge – single bi-directional platform – 6.3 miles South of Cowden
• Crowborough – two platforms
• Buxted – single bi-directional platform – 4.7 miles South of Eridge
• Uckfield – single platform – 2.3 miles South of Buxted

Suppose the following were to be done.

• Do nothing at the two platform stations.
• Fit an intelligent fast charging system at Cowden, Eridge, Buxted and Uckfield.
• If it was felt to be needed to ensure reliable operation, the power supply to the Southbound platform could be boosted at Hurst Green station.
• Procure some ten-car battery-electric trains, which have regenerative braking and a range of perhaps ten-twelve miles on battery power.

Note.

1. A pair of five-car trains could be used instead of ten-car trains.
2. Some five-car Class 377 trains fitted with batteries might be ideal.
3. This would mean only four platforms would need to be electrified with fast charging systems.

I am sure that Vivarail Fast Charge systems could be used, if they were modified to work with standard third-rail systems and for bi-directional use.

What size of battery would be needed for this approach?

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 is not very challenging.

A modern EMU needs between 3 and 5 kWh per vehicle mile for this sort of service.

So for a ten-car train running for twelve miles, the train would need a battery capacity of between 360 and 600 kWh.

Or if it was two five-car trains between 180 and 300 kWh in each train.

Note that Vivarail find space for 424 kWh in the two-car Class 230 train, I wrote about in Battery Class 230 Train Demonstration At Bo’ness And Kinneil Railway.

I believe that a five-car Class 377 or 707 train could be fitted with a 300 kWh battery and this would give the train a range of 12 miles, which would enable it to provide a battery-electric service on the Uckfield Branch.

May 2, 2022 - Posted by AnonW | Transport/Travel | Battery-Electric Trains, Class 377 Train, Class 707 Train, Electrification, Uckfield Branch, Vivarail Fast Charge