Dr STEPHEN POTTER’ S PRESENTATION ON "RAILWAYS IN SUSTAINABLE
COMMUNITIES"

There was much useful information in this excellent presentation, a summary of which is attached.

The choice of a Eurostar train as an energy comparative for high-speed rail with other modes was a little unfortunate as these trains embody design features that made them unique to Channel Tunnel operations, much of which has proved unnecessary and would not be included in a high-speed train service from London to Scotland.

As built, it should be noted the Eurostar trains had 780 seats, not 700 as shown in the tables. The refurbished examples have seating reduced to 750, no doubt to accommodate disabled toilets etc, but this capacity would still produce a figure of 0.58 megajoule/seat km, not 0.62 as shown.

In common with most rail services of late, passenger loadings have increased and average occupancy may well now exceed 40%.

The decision to build Eurostar trains with 18 coaches was not a commercial decision but is related to a requirement by the International Safety Commission for the trains to have sufficient capacity for the passengers in one half of the train to be accommodated in the other half in the event of a fire, whereupon, the train could be split at the centre and the undamaged half hauled to safety by the remaining power car. There is a power car at each end.

Furthermore, because the Channel Tunnel contains sustained severe gradients at each end, each power car was required to have sufficient power to haul the entire train out of the tunnel in the event of a failure of the other and these trains therefore have a higher power-to-weight ratio than would otherwise be necessary for operation at 300kph (186mph).

Up to now, the restricted British loading gauge has prevented the use of double-deck trains but a number of routes are likely to be cleared for W10 loading gauge for carriage of 9ft 6in containers on standard flat wagons and this would also provide sufficient clearance for double-deck trains in the future. Any new high-speed rail network would be designed for use by double-deck trains which provide a step change in energy efficiency.

As a matter of interest, an Autocar "Road Test" of one of the original single deck 300kph TGV trains found it could carry 375 seated passengers for 0.75 miles on the oil equivalent of a gallon of fuel, equal to 281 passenger miles per gallon and no less than 94 x 4 seater cars capable of 70 miles per gallon at 186mph! That is close to the maximum speed of a Formula One racing car which typically manages about two miles per gallon with one occupant.

The “Duplex” double-deck TGV carries 570 passengers in the same eight-car train length and, with the latest energy-efficient technology, could be expected to produce 430 or more passenger miles on the equivalent of a gallon of oil based fuel. Regrettably, I do not know how to relate this to Mj per passenger mile but perhaps Dr Potter could help?

Finally, I understand work is now to take place to provide the modifications to use regenerative braking on the ex Southern DC rail network which will improve the suburban electric trains energy efficiency by 10 to 15%.

Norman Bradbury 5 March 2006

RAIL’S ENVIRONMENTAL PERFORMANCE COMPARED:

MJ per seat kilometre MJ per passenger kilometre Occupancy

Eurostar 0.62 (0.58 with 750 seats) 1.6 40

Electric Inter City 0.5 1.2 40

Electric suburban 0.39 1.0 40

Light Rail 0.18 0.7 25

Double Deck Bus 0.22 1.1 20

Average Car 0.91 2.1 42

Air, Domestic 1.5 2.1 70

Notes: It should be noted that carbon emissions at high altitude from aircraft are twice as damaging than the same emissions at ground level and therefore the figures above for air should be multiplied by a factor of two.

In practice, the average car occupancy is only about 35% and rail average occupancy has increased in all cases.

Commuting by suburban train now uses O.65 MJ per passenger kilometre compared to 3.04 for a medium size car (in congested conditions).

Commuting is only 20% of total travel (but is higher for rail travel). Moving to small towns will increase car use for 80% of trips and commuting trips have become longer.

Ideally, rail commuting should be promoted with measures to minimise distances and promote walking and cycling to stations.

Chiltern's "taxi bus” at Bicester has reduced car commuting to the station at peak times and freed up parking spaces for off-peak leisure travel.

Given current trends, by 2050 air travel will be responsible for 33% of carbon emissions while, technically, air will continue to be reliant on high carbon fuels (oil) while rail can switch to low-carbon fuels.

Building a high speed north-south raIl line would not only reduce damaging air travel but would also provide increased capacity on the existing network for more local, regional and freight trains which could generate further modal switch from road traffic and yield additional environmental benefits. Care would need to be taken, however, to limit longer distance commuting.

Hypothecation of motor and local taxes could be used to support local rail and light rail services. Road charging in Norwegian cities has been used to help fund light rail systems and a 25pence surcharge on parking at Heathrow airport was used to help fund Heathrow Express. Benefits to road users include reduced road congestion and accidents.

Developers, as has happened at Milton Keynes, could be required to pay a “roof tax” to fund local transport infrastructure.

Rail investment also stimulates regeneration while noise is an issue that mitigates against air rather than rail travel.

Stephen Joseph made the point that on the London-Paris run, a Eurostar is reckoned to produce 1/14th of the carbon dioxide per passenger/kilometre of air travel but this is partly due to French nuclear-generated electricity.


Norman Bradbury
5 March 2006