The Indian railways are getting rid of their locos and stock and replacing them with MU even though the MU's are more expensive:
http://www.railwaygazette.com/news/single-view/view/india-plans-inter-city-emus-to-raise-speeds.html
Are they being silly and wasting money on over priced MU's when Locos would be better?
There might be a political component to the decision. But it depends on the precise nature of the route and all sorts of factors. And are they really replacing with EMUs or what? The Pendolino is not an EMU but a fixed formation unit train. The X2000 looks like an EMU but is not - these are locomotive hauled sets running in various and easily altered lengths in push-pull mode and capable of running in pairs of up to about 12 coaches. And the HST is a locomotive-hauled train.
NO, because the MU's would pay for the cost difference in 3 years! 3 years, of a 40 year train life span, that then means that they have another 37 years (or a factor of 12 over the break even point) where the better running costs are bring in extra profit for them.
That is barely credible. How can they make this saving? For a start, it implies the withdrawal and replacement of all the existing vehicles.
One of the main reasons given for this is because of extra capacity, which is massively important to the UK railways.
I have listed before the capacity of the IEP trains would provide over the other options put forward and how they get more passengers per length of train than any other option, which means that we do not have to invest in infrastructure to improve capacity and/or have more stations with SDO, which allows for some future proofing of the network. Which given the rate of growth of the railways is essential.
What you say is true as a generalisation. A locomotive is a box of equipment which cannot be used for revenue-earning purposes. Where platform lengths are critical it is advantageous to put it under the floor. But there are costs in doing so, for example, the capital cost per vehicle is higher if they are all powered, and it comes at the cost of comfort if it is diesel power.
In practice, however, on routes where the longer IEP is proposed, how many stations are actually subject to length restrictions and which are they? What appears to be the case, as the debate unfolds, is that the routes in question could be served by conventional electric trains on the electrified sections, and locomotive haulage on routes which are not electrified throughout.
Also, although SDO could be used at more stations there comes a point when it means that carriages are under used. For if you build a train too long for most stations along a line, including a few key stations the carriage(s) which rarely stop at platforms would not be used, or the dwell time at each station has to go up to allow for passengers finding that they cant get off from their carriage. As well as having to have a lot of automated announcements telling people in the relevant carriages that they have to move to another portion of the train (potentially with a large amount of luggage) which is just going to annoy everyone, especially if the seat booking system books your seat in the wrong carriage for you to get off the train from it at your station. All in all SDO is only OK if it is used at a few stations along a route where the numbers of passengers for those stations are fairly low and the numbers of passenger travelling between the stations where SDO is used is very low.
How do things actually function? The present Waterloo-Exeter and the old Waterloo-Weymouth operations are examples of the sort of compromises that occur - less than perfect but they work and do not cost an arm-and-a-leg. Bi-mode would allow the use of electricity all the way to Basingstoke, and to Salisbury if electrification was extended. This would avoid running nine car DMUs. But west of Salisbury the traffic is light so three-car trains are the standard formation. Waterloo-Weymouth trains were operated as 12 car trains with 2xTC units unpowered and the REP unit with enough power to drive the whole train. The REP was left behind at Bournemouth whilst the TCs were pulled to Weymouth and pushed back. TCs could also work with class 73 locomotives. The system was flexible, sophisticated and technically simple.
Sorry but these locos are expected to run for 35 years, they will have no use when the lines are electrified, they will wast massive amounts of energy (in their construction). I can't believe people are willing to condone this waste.
Presumably you are referring to the use of new diesel locomotives in the UK? There will be plenty of non-electrified routes in 35 years time. But to judge from everything that has been said on the subject, it sounds as if the easiest solution for routes that are not electrified throughout, but for which through services are required, is to soldier on with HSTs for as long as they can be kept going. That way, no massive amounts of energy need to be wasted in the construction of anything.
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If you buy new diesel locos then the business case for electrifying a line drops, which means that the services running on it have to be run by diesel for longer (as other lines would then jump the queue to be electrified).
It also allows short lengths of electrification to be done without upsetting the change point for the loco. For instance if the line between Oxford and Moreton-in-Marsh was electrified then the mini depot (suggested by others and by the way no one has explained how they are going to staff it in a cost effective way yet) that has just been built for storing, refuelling and minor maintenance on your loco's at Oxford is now in the wrong place. Whilst with bi-modal it causes no such problems and the train just runs under electric traction for longer (reducing CO2 emissions).
Once IEP is in service, where is the business or any other case for extending electrification from, say, Oxford to Moreton in Marsh? IEP kills it stone dead.
As another alternative what do you do about the East Coast services which run to Inverness, do they add a loco and run under existing wires before they peal off (at a station which is not suitable for adding a loco at), or by having a Bi-modal train run using electric traction until the wires stop and then run using diesel power?
You continue to run diesel all the way from London to Inverness. How many trains a day run the entire length of the route?
The extra cost and waste of energy to lug engines and fuel around is fairly small.
Yes.
Also as stated before because of the better use of internal space it is likely that there will be less carriage weight per seat, which would further offset the extra weight of the engines and fuel. It is also a whole lot lighter than the weight of any loco, which has to be lugged about off the wires.
The comparison is to add up the weight of all the traction equipment that is under the floor that would then go in a locomotive. There will be a break-even point. The extra weight of the loco hauled train is that of the locomotive as an empty "box". But remember that powerful underfloor diesels are not nice things to have to sit on top of for hours on end. And compliance with emission regulations is easier to deal with at one go with a single large engine.
The other thing to bear in mind is that the fuel tanks could run fairly empty (so less chance of overspill when filling them as they would not be being filled to the top) on services which are running solely under the wires as they wouldn't need much fuel to keep hospitality going for several hours and/or to limp to the next point where there was power or the next station. Even those services which were running beyond the wires wouldn't need to carry as much fuel as a train which is running solely by diesel (which in all likelihood is what the DfT was comparing against).
Sounds tricky in practice.