if those figures are accurate really they should order an entirely bi-mode fleet, as they claim that energy use by the two types will be the same under electric power.
I don't think they ever claimed that. In Modern Railways August 2011, there was a DfT claim that fuel costs for a 5-car bi-mode under the wires were 2 pence per mile higher than the 5-car electric. I think those figures were later found to be inaccurate, but even given they seemed to be making up numbers DfT were still admitting bi-mode would cost more.
There are 3 currently unwired ECML desinations in England; Hull, Lincoln and Harrogate. Hull seems to be a strong candidate for inclusion in the TP North electrification and Harrogate makes a strong case as a commuter line although nothing specific has been announced. If Harrogate were wired, and if Lincoln were served by the EMT franchise (should it retain some 222s) then the EC franchise would not require bimodes for its English routes.
The EC franchise has only one train per day on each of those routes anyway. Even if none of them were being wired, I'd say the frequency doesn't warrant bi-modes, just drag an EMU the last little bit with a diesel loco. You'd need 1 loco max in service for each of those three, whereas you'd need to build rather more bi-modes since the diesels would be carried under the wires to London and back. I think Scotland are talking about wires further north too, and the ammount of under-wires running from KGX to Scotland, even for a bi-mode, is obscene. Please just attach a diesel loco when the wires run out (or order more electric IEPs, to cover some IC225 diagrams, and use the released IC225s on the Inverness and Aberdeen runs with a loco swap for a TDM-fitted diesel somewhere around Edinbrough).
PAD - Worcester/Hereford and the proposed PAD - Westbury semi-fast are the only places proposed for bi-mode IEP that ever made sense in my opinion.
I don't understand why GC (and FHT for that matter) haven't thought about adding a few extra 5-coach, bi-mode units to the ECML, rather than ordering the supposed China-sourced Polaris units. Surely it would be cheaper, plus it would make maintenance and breakdowns easier to deal with. But what could be done with the 180s?
If Hull gets TPE wires, then hopefully Hull Trains would get some electric units. They might not have the money for new stock though and just run their 180s under the wires. Some IEPs might be a good idea if they can share depot facilities with EC. Grand Central would probably need bi-modes though, or would stick with 180s and IC125s. I think the extensions of the proposed PAD - Westbury semi-fast would be a good place to put any class 180s that are released.
It does, doesn't it.
I wonder if it's the draft consultation that is wrong, or all the armchair IEP experts posting here and elsewhere?
Most of what I've seen (and extracted from DfT representatives over e-mail) has suggested that PAD - Carmarthen is planned to be bi-mode IEP, and that the line would be cleared. The lines west of Carmarthen (to Pembroke & Tenby, and to Milford Haven where some would like to see the Carmarthen trains extended to one day, and to Fishguard where any erupting Icelandic volcanos could prompt a desire for short-term reinstatment of through London trains) however are not on any list I've seen for IEP clearance, Pembrokeshire is an IEP no-go zone.
So, Swansea - Carmarthen (and maybe the Swansea District Line for diversions) is being cleared for one train a day (maybe three on Sundays) (the two extras on summer Saturdays are out, since they go to Pembs). Completly mad, use 23m coaches to save the clearance money and allow the trains to continue into Pembrokeshire! If the service to Carmarthen has to be bi-mode, then can it be an extension of the PAD - Cardiff trains rather than PAD - SWA services (then it can run via the SDL instead of via Swansea). My prefered option is to attach a loco at Swansea (or use a push-pull LHCS set and swap electric loco for diesel loco there), but this means going via Swansea as it is probably rather harder to mess around with locos at Cardiff.
Is MML and Swansea wiring confirmed now? Or are you lot just guessing that will come out in Monday/Tuesday's HLOS anouncment?