The Anonymous Widower

Why We Should Use Independently-Powered Electric Trains

I was looking for something else and found this article in the Henley Standard entitled Goring rail line work ‘will ruin countryside’. This is said.

THE electrification of the railway line through Goring will ruin the surrounding countryside, say residents.

Network Rail is installing overhead power cables as part of the scheme, which covers the route between Reading and Oxford and is expected to be finished next year.

Last week contractors began felling trees and putting up steel lattice gantries which will span the track at regular intervals to hold the wires in place.

You can argue that on a major line like the Great Western Main Line, we need robust overhead wire systems, as many of us have suffered serious delays on lines like the East Coast Main Line and the Great Eastern Main Line because of the flimsy overhead wire design.

But still the residents have a point and I think there must be a better design that mitigates the visual intrusion. Would Jasper Maskelyne and others skilled in the art of camouflage have ideas to assist Network Rail?

Network Rail can get it right, as is shown at the Grade 1 Listed Wharncliffe Viaduct, where the overhead wires are arranged to reduce the visual impact.

Are they usually as measured about where they place a gantry, as they have been on the viaduct?

Away from main lines, there will be lines like the Settle and Carlisle and the Hope Valley Line, where visual intrusion will be very important and activists will attempt to stop the installation.

It is for places like this where we must have independently-powered trains to service the route. There are two available technologies.

Electro-Diesel Trains

At the present time, there is only one electro-diesel train planned in this country and that is the Hitachi Class 800 train, which soon be seen on the Great Western Main Line and the East Coast Main Line.

They are a solution to the problem and can switch between propulsion modes at line speed, but they require diesel engines to be lugged around the country for where they are needed, so they may not be as efficient as a purely electric train.

There seems to be a few ideas for electro-diesel trains, but none appear to be comng to fruition.

Electric Trains With On-Board Energy Storage (IPEMU)

I rode the Class 379 train, that had been converted to act as a demonstrator for this technology.

It was impressive, as we trundled through the Essex countryside powered by energy stored in batteries, that had been charged from the overhead wires.

The fact that the technology works is all down to the physics of steel wheels on steel rails, which make train travel efficient in the first place.

As an electrical engineer, I know that this is technology, that can only get better.

• Electricity storage, whether based on batteries, flywheels, capacitors or some other method, will only get better.
• Trains will roll better through improvements in design.
• Energy harvesting from sources like regenerative braking will be more comprehensive.
• Secondary electrical systems on trains like air-conditioning, toilets and the provision of wi-fi will use less electricity.
• Automatic control systems will control the train tightly according to schedule, terrain and signals to minimise electricity use.
• Pantograph deployment will be automatic, when overhead wires are available.

But using the on-board storage to power the train on its route, is only one of the reasons it will be installed.

• If a train has on-board storage and regenerative braking, it will be more efficient.
• When the overhead line gets damaged or the power supply is cut, an electric train with on-board storage might still get through.
• Depots can have simplified electrification, which is safer for staff.

Bombardier must be impressed with the concept, as all Aventra trains will be wired so that on-board energy storage can be fitted.

Conclusion

Both technologies for independently powered trains are proven, but you wouldn’t want to use on-board energy storage over more than a limited distance, beyond which the diesel would be ideal.

By using independently powered trains, you can balance electrification cost, installation disruption and visual intrusion against the extra cost of a train with on-board storage or diesel engines.

Provided of course, the independently powered train can handle the route to the satisfaction of passengers and rail companies!

On the Great Western Main Line because of the distances involved and the reliability required, electric trains using overhead power on robust supports are probably the best method we have at present.

Although, Great Western Railway have been reported as saying they might use Class 387 trains with an IPEMU capability to destinations a few miles off the Great Western Main Line, like possibly Bedwyn and Oxford.

December 10, 2015 - Posted by AnonW | Transport/Travel | Class 800 Train, Electrification, Great Western Railway, IPEMU