die belebende Bedenkung

Rolling stock is cheaper than infrastructure

with 3 comments

In his observations on cost-effective upgrading of Amtrak’s Northeast Corridor, Alon Levy noted that, in general, rolling stock is cheaper than infrastructure, and that planners should worry about track capacity when all other capacity factors have been optimized.

An intercity railroad that runs 8-car trains is definitionally not at capacity.

These remarks are equally true for the rail network in Great Britain. Despite what Andrew Adonis (and perhaps Sebastian Coe) might think, Britain’s trains are generally not “stuffed to the gunwales”. Most seats are empty, most of the time, so addressing instances of peak crowding by building HS2 makes no sense. HS2 makes the overcapacity problem much worse, by expanding it from a rolling stock issue, to an infrastructure one.

London rail passenger arrivals by time of day, 2011

London rail passenger arrivals by time of day, 2011. The area coloured orange represents unused seating capacity. The green arrowed line shows the difference between circulating seats and occupied seats. The blue arrowed line shows the difference between total seats and occupied seats. Seat utilisation of departures has a similar distribution, but with the hump occurring in the evening. Total seats includes those of trains returned to sidings out-of-peak.

Intercity trains on the Chiltern Main Line (CML) are not even eight carriages long, so to use Mr Levy’s phrase, it is “definitionally not at capacity”. It is massively cheaper to create additional capacity by lengthening Birmingham trains (and increasing frequency) on CML, than it is to build HS2. The resulting freed paths on the West Coast line could then be reallocated for additional trains to north-west England.

Written by beleben

August 1, 2012 at 2:46 pm

Posted in High speed rail, HS2, London

Tagged with ,

3 Responses

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  1. Are the platforms long enough, or at least easy to lengthen? One of the hidden points of that post is that on the Northeast Corridor, the answer at nearly all Acela stops is yes (and the only one where it is genuinely difficult to lengthen the platforms, New London, is the least busy and also easiest to bypass on a high-speed alignment). South of New York the platforms are all at least 12 cars long thanks to work done by the Pennsylvania Railroad, and either already are or can be lengthened to 16; north of New York it’s a bit harder but still possible to lengthen everything. If the platforms on the WCML are in very constrained locations, it may not be as easy to lengthen them. One of the things I’ve read elsewhere is that the reason they’re building HS2 out of Euston and not, say, Paddington, is that Euston is the only place they can level and rebuild with long platforms. (Still nowhere near £33 billion, but still, something to think about.)

    Alon Levy

    August 2, 2012 at 12:33 am

    • Capacity is touted as the key reason for building HS2, but does not rank highly in its Economic Case. On the West Coast Main Line, lengthening of some Pendolino long-distance trains from 9 to 11 carriages is currently being done, but extension to 12-or-more would require platform lengthening and track works along the route. That is politically sensitive, because of cost over-runs that happened when the line was last upgraded. But on the southern part of the WCML, used by London commuter trains, platforms have been lengthened for 12 carriages.

      The Chiltern Main Line is a second railway between Britain’s two largest cities, on which much shorter trains run. It could be argued that

      * it would make sense to make more use of the CML, by building suitable platform capacity in London and Birmingham,

      * redistribution of some traffic to CML could do away with the need to lengthen WCML platforms in the foreseeable future.

      As far as the Northeast Corridor is concerned, I’m a little surprised that there aren’t parallel routes, that could be used to stratify traffic. I suppose they were closed in the consolidation that led to Conrail, etc.


      August 2, 2012 at 11:56 am

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