IEP becomes key to Great Western ‘sparks effect’

The government’s much-criticised Intercity Express Programme (IEP) of new long-distance trains is emerging as the key to electrifying lines such as the Great Western.

Sources suggest that while the electric and dual-power versions remain, it is likely the diesel-only variant will be dropped as plans concentrate on a train that can work under electric wires and then beyond.

One insider told RAIL it was IEP that made the business case for Great Western’s overhead wires by providing a ‘ready-made’ train in time for the wires to be erected, possibly in the second half of the next decade, But, he added, the wires will never reach Penzance, although as through trains from London would remain it was vital that IEP contained diesel power to work away from wires.

He explained that although IEP’s 3,600hp diesel engine would have less power than today’s High Speed Trains (HST) it could more effectively apply this power to the rails and so produce higher acceleration than HST. IEP will apply power through traction motors spread the length of the train (distributed power) in the same way as Alstom’s Pendolino EMU.

It is distributed power that gives IEP’s on-board engine the edge over the more traditional method of using standalone diesel locomotives to haul electric trains away from overhead wires (OLE) because, again, IEP can more effectively apply its power to the rails than a locomotive, RAIL understands.

The ‘all-electric’ IEP is likely to have a small auxiliary diesel engine to allow it to move around depots, on the main line in emergency and to keep lights and air-conditioning working should the overhead power supply fail.

Testing of pre-series and then production train is likely to take place on the East Coast Main Line, and will allow problems to be solved and operating experience to be gained in time for the Great Western to benefit. ECML will keep IEP as a replacement for the Class 180s that National Express East Coast still hopes to receive, HSTs and Class 91s. The latter, and their Mk 4 coaches, will be some 25 years old by the time IEP is introduced, and are being so intensively worked that there is always one rake being refurbished despite the million miles they run between such work.

The Department for Transport is procuring IEP in both half and full train lengths to allow operators to match capacity to demand. Internal documents seen by RAIL suggests that half-sets will be suited to 125mph off-peak trains between London and Northampton or Oxford.

It is believed DfT will soon announce its preferred bidder for the project, following December’s postponed announcement. Two consortia are bidding: Hitachi with Barclays and John Laing; and the Express Rail Alliance consortium of Bombardier, Siemens, Angel Trains and Babcock & Brown.

• This news article was originally published in RAIL 610, on 28 January 2009