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You’ve gotta have a system

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Renfe, Memoria 1983As late as the 1980s, compared to most western European countries, Spain’s national railway network was antiquated, and provided a distinctly odd customer experience. I remember a Largo Recorrido journey from a few years ago, where the train, nearing Madrid, was shaking so violently that I thought it had come off the rails.

Since then, there has been massive investment in parts of the system, particularly the Cercanias and new build líneas de alta velocidad (LAV), along with sectorisation of train operations, and separation of infrastructure from production.

Spanish practice has been to build LAV as freight-capable, and unlike the legacy network, standard 1435mm track gauge is used (at one point, wholescale conversion of the 1668mm network to 1435mm was under consideration). Outside of the big cities, investment in the legacy system has remained modest.

Given the limits of its legacy road and rail infrastructure, the construction of some LAV track could be seen as being justified by its developmental and connectivity benefits.

However, as of 2012, the AVE network is said to be the second longest in the world after China, and there is evidence that much of the investment does not live up to the hype.

In his presentation ‘Energy consumption of High Speed trains‘ for the UIC High Speed Rail 6th world congress in Amsterdam (2008), Alberto García Álvarez of the Fundación de los Ferrocarriles Españoles claimed that Spain’s new build high speed rail (AVE) was more efficient that its legacy network, and a similar efficiency disparity was likely in other countries.

Alberto García Alvarez, Energy consumption of High Speed trains (2008)

Alberto García Alvarez, Energy consumption of High Speed trains (2008)

He described the AVE as a ‘system’, in which each part contributed to the efficiency.

García Álvarez, 2008 presentation -  'high speed rail is a system'

Sr García Álvarez was using the notion of efficiency within a narrow confine. For example, it would be challenging to describe the manufacture and storage of large amounts of surplus AVE rolling stock as ‘efficient’. As the AHT Gelditu website noted,

Renfe se ha gastado 1,400 millones de euros en trenes de alta velocidad innecesarios.

According to Sr García Álvarez

  • a Madrid to Lleida journey using the AVE line in a S-102 emu worked out 32.6% faster than a conventional Grandes Lineas journey, while using 15.7% less energy
  • on the wider AVE network, better energy efficiency came from
    • a more homogeneous speed profile
    • lower point to point distance
    • lower ancillary services consumption
    • lower mass per seat and “smoother trains”
    • a more efficient aerodynamic profile
    • bigger trains
    • better load factor, and
    • a more efficient electric system.

Sr García Álvarez argued that system efficiencies would more than offset the higher traction energy arising from increased velocity. However, since the raw data isn’t available, there is no way of assessing the relative efficiencies of particular aspects of the AVE system. The energy inefficiency from increasing speed does seem to have troubled the Spanish government. In a 2007 El Mundo report, transport minister Magdalena Álvarez seemed unconvinced of a case for ever-higher commercial speeds.

[Magdalena] Álvarez comentó que, aunque el AVE S-102 Talgo Bombardier puede alcanzar los 330 kilómetros por hora (km/h) y el modelo Siemens que sustituirá a los Talgo llega a los 350 km/h, la velocidad comercial de la alta velocidad en España será de 300 km/h como máximo. Con ello descartó así algunas previsiones iniciales que apuntaron a que en la línea Madrid – Barcelona se podrían alcanzar los 350 km/h.

Furthermore, Sr García Álvarez’s pitch does not take account of what might be ‘showstopper’ issues in other countries, such as the embedded carbon from AVE construction, or the very low utilisation of the new infrastructure.

Improved aerodynamic design and lower seat mass can be designed into 200 km/h trains too, so Sr García Álvarez’s conflation of speed and non-speed factors obfuscates the energy impact due to running at high speed. Similar obfuscation is practised by HS2 lobbyists in Great Britain.

Sr García Álvarez’s claims


Claim 1: “It is not true that [high speed rail] energy consumption increases with the square of the speed, and the needed power with the cube”

The energy involved in constructing and operating a high speed rail system is more than just the energy used to propel the trains. But as far as traction energy is concerned, it is more or less correct to say that consumption rises as the square of the speed.

So for a railway where trains ran uniformly at 400 km/h, energy consumption would be more than three times that of running at 200 km/h. No amount of lower “mass per seat, better aerodynamic profile” spin is going to alter that fact. In real world high speed lines, trains tend to run well below advertised ‘headline’ velocity for large parts of the journey, so the overall energy multiplier would be lower.

High speed rail, energy requirements of TGV-R and AGV11 (Systra)

Very high speed trains would have lower ancillary (train heating, lighting, etc) energy take, but ‘hotel’ power is not a particularly large part of consumption per-journey. And because ancillaries are generally left on in idle time between peak diagrams (etc), the actual AVE hotel energy saving may not be that large.


Claim 2: “Figures show that in general, HS trains have a similar energy consumption (many times lower) than conventional trains”

Trains running at higher speeds use more energy per kilometre. In Great Britain, HS2 Ltd has accepted that its trains would have higher energy consumption than Pendolinos on account of higher speeds.

New build AVE tracks in Spain are straighter than legacy routes, but in Britain the Bicester cut-off route to Birmingham is much the same length as the HS2 equivalent. Whether the Y network would be shorter than its classic analogue, remains to be seen. The Y network route is currently secret.


Claim 3: “HS (just because of the speed) can capture passengers from all means of transport, especially cars and planes”

In Great Britain, there is little doubt that high speed rail could capture passengers from cars and planes. For example, if high speed rail lines and bridges were built to the Scilly Isles, Shetland, and Larne in Northern Ireland, there would be be modal shift to rail from air, and new rail journeys. But modal shift is peripheral to the question of whether such investments could produce net economic benefit. In the case of HS2, the modal shift expected from air and car travel was estimated at just 3% and 8% respectively by HS2 Ltd.

Renfe, red 1983 [Beleben], showing capacity limitations

© Beleben 2012

Written by beleben

August 17, 2012 at 2:43 pm

Posted in High speed rail, HS2

Tagged with , , ,

Marshall moonshine

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High speed rail travel at 400 km/h requires 3.2 times as much energy as 200 km/h (Systra for Greengauge21)

Like Siemens’ ICE3, the Alstom AGV is a ‘distributed traction’ high speed train (in which traction motors are dispersed beneath the carriages, instead of having power cars at each end of the trainset). The 200-metre long AGV11 variant was used by HS2 Ltd as its ‘Reference train’ in the development of its proposed Y network between London, Birmingham, Leeds, and Manchester. And according to Railnews writer Alan Marshall

the AGV uses no more energy (nor generates any more carbon dioxide) per seat at 300km/h (186 mph) than a Virgin tilting Pendolino (based on an earlier Alstom design) running at only 200km/h (125 mph) on Britain’s West Coast Main Line.

Mr Marshall claimed that the ‘AGV’s ‘green credentials’ were disclosed in an analysis in an April 2009 ATOC (Association of Train Operating Companies) report by Richard Davies and Leigh Thompson.

ATOC undertook the analysis of carbon dioxide (CO2) impacts of High Speed Rail for Greengauge 21, the not-for-profit organisation established in 2006 to research and develop the concept of a High Speed Rail network.
[…]
The report also makes clear that rail’s ability to improve its carbon footprint by carrying more passengers with the same energy consumption is constrained by Britain’s restricted structure gauge and the inability of the infrastructure to permit operation of very long trains — whereas a new line will enable longer trains with duplex accommodation, so the energy demand per seat kilometre can be kept very low.

“A double-deck, double-unit TGV Duplex train, for example, offers 1,090 seats in twenty vehicles compared to the 439 seats that the nine-cars of a Pendolino can offer — a significant capacity advantage that would remain even after most of these have been extended to 11 cars,” said Davies and Thompson, who added: “The trains used are also typically longer, so that the aerodynamic drag of the front end of the train (which is a significant energy cost at high speed) is spread over perhaps 16 to 18 carriages rather than the UK norm of eight to 10 carriages.”

A new AGV operating at 300km/h will consume 0.033 kWh of electricity per seat kilometre, they say. The AGV’s construction and distributed power system along the train means the total mass per seat is just 0.78 tonnes. By comparison, a Virgin Pendolino on the WCML has a mass per seat of 1.055 tonnes — 35 per cent greater than an AGV — so at only 200km/h (125mph) its energy consumption is the same as the AGV going 50 per cent faster.

A Eurostar — a TGV scaled down to fit within the UK structure gauge — has a mass of 0.96 tonnes per seat and an energy consumption of 0.041 kWh per seat/km.

What useful conclusions can be drawn from the ATOC ‘research’? The answer seems to be: none whatsoever. Comparing the energy per seat of a 9-car Pendolino at 200 km/h and a HS2 Reference train (AGV) at 300 km/h is not informative. HS2 is planned as a 400 km/h railway, with trains running, from the very start, at 330 km/h or more. Hyping AGV ‘reduced train mass’ is not going to be particularly helpful at 300 km/h or above, because at those speeds, aerodynamic drag is the major factor in train energy consumption, and energy required rises steeply (approximately as the square of the speed). A less misleading energy per seat calculation would be: 11-car Pendolino at 200 km/h, versus AGV11 at 330 or 350 km/h.

Neither the cruise speed nor the maximum speed of trains on the Y network is planned as 300 km/h, and the energy per seat calculations favoured by ATOC obviously take no account of load factor. The primary statistic for comparison should be energy per passenger-kilometre, not energy per seat-kilometre.

Spreading the aerodynamic drag of the front end of the train “over perhaps 16 to 18 carriages rather than the UK norm of eight to 10 carriages” is never going to be of much use, if most of the carriages are empty. When the 18-car Eurostar service between London, Brussels, and Paris first started, the load factor was very low (reported as around 20%), so the seat-kilometre and passenger-kilometre energy measures would give completely different messages.

HS2 Ltd gave the overall load factor forecast for its new line as 58%, which is higher than the average for British long distance high speed services, but nowhere near high enough to compensate for the additional energy its trains would use. HS2 is planned to have ‘similar fares’ to the legacy network, which obviously poses a credibility problem for the ‘58% load factor’. If the HS2 fare structure is going to be similar to the legacy network, how could its load factor be significantly higher? Answers on a post card to: Andrew McNaughton’s There’s-No-Answer-To-That Waste Paper Basket, HS2 Ltd, Eland House, London, SW1.

The claim that

rail’s ability to improve its carbon footprint by carrying more passengers with the same energy consumption is constrained by Britain’s restricted structure gauge and the inability of the infrastructure to permit operation of very long trains — whereas a new line will enable longer trains with duplex accommodation, so the energy demand per seat kilometre can be kept very low

is drivel. On a per-metre length basis, an AGV has no more accommodation than a British loading gauge train (such as a Pendolino). The AGV is currently not available in a double deck version, so its larger cross-section makes its less aerodynamically efficient than a modern standard train built to British loading gauge.

HS2 would certainly not permit generalised operation of longer passenger trains in Britain. Indeed, the standard (off-peak) train length in the HS2 scheme is 200 metres, which is shorter than existing trains like the Pendolino. Operation of 400-metre long HS2 trains would only ever be possible on the new build track — which would only serve London, Birmingham, Leeds and Manchester directly.

Written by beleben

May 14, 2012 at 4:08 pm

Moving Birmingham to Manchester

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In Britain, very little information is available about energy consumption, efficiency and emissions of public transport. In the rail industry, operators haven’t shown much interest in rolling stock efficiency (for example, most electric trains are not equipped with energy meters), and privatisation has introduced issues of commercial confidentiality.

Energy consumption is a particularly difficult area for the high speed rail lobby. According to an April 2007 press release, Virgin Trains’ regenerative braking saved 17% of energy, and on a typical London to Manchester journey, a Pendolino would return around 750kWh of electricity to the power supply system. This suggests that the energy required for a London to Manchester Pendolino is about 4400 kWh.

According to HS2 Ltd, the 200m HS2 Reference train running from Euston to Birmingham Curzon Street, with two stops, would consume 4700 kWh (after regeneration benefit of 437 kWh).

So, from London, a HS2 train is likely to use more energy to reach Birmingham (174 km), than a Pendolino would use to reach Manchester (298 km). It’s worth bearing in mind that Pendolinos tend to make more intermediate stops, which would add to their energy consumption.

Written by beleben

September 9, 2011 at 11:44 am

HS2 traction energy

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HS2 Ltd’s document, ‘Traction Energy Modelling’ Version 1.1 of 31 December 2009

summarises the traction power energy assessment for High Speed 2 operation using the HS2 Reference train. This analysis is required to understand the traction energy consumption of the HS2 reference trains for CO2 comparison and also energy consumption comparison in kw-h/seat km.

The corridor used was the 174 km Birmingham Fazeley Street (Curzon Street) to London Euston ‘Route 3’, but the make and model of Reference train was not identified. Following freedom of information requests, it emerged that the Reference train was the AGV11 variant of the (Continental gauge) Alstom Automotrice à Grande Vitesse. The base assumption for stops included Bickenhill and Old Oak Common, but scenarios included one where trains stopped halfway (near Newton Purcell, Oxfordshire). Exactly why this location was chosen to model the effect of an additional stopping point, was not explained.

  • The modelling was done by Robert Watson, Anouk Dufour, and Diem Tran Thi Ngoc from the Future Railway Research Centre (FRRC) at Imperial College, but with no access to primary data; they were totally reliant on what the manufacturer provided them with.
  • HS2 Ltd have referred to 200-metre units carrying around 550 passengers, operating singly or in pairs (1100 passengers). However, the single 11-section AGV seating is only 510 (high density) or 458 (standard density) in Alstom publicity.
  • AGV11 maximum speed is sometimes given as 350 km/h, other times as 360 km/h. The Reference train maximum was 360 km/h. HS2 Ltd claimed that 61 trainsets would be built for the phase one scheme, 45 of which would be classic compatible, and the remainder Continental GC gauge.
  • At Innotrans 2008, Alstom gave AGV floor height as 1155mm; this does not match the floor height for rolling stock intended for use on HS2.
  • Load factors modelled were 100% and 70%. However, the general load factor assumed for HS2 (outside of traction energy modelling) is lower (58%). If operations followed SNCF practice, passengers would be seated on HS2 runs, so it’s probable that a second HS2 200-metre unit would often need to be provided, running largely empty.

Written by beleben

September 8, 2011 at 9:10 pm

Rip-off at the doorstep

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Centrica plc (‘British Gas’) today announced that

its field sales agents will cease doorstep energy sales activity for an initial three-month period. This in line with a request to all suppliers made by Consumer Focus. The energy provider will now work with its customers and consumer bodies to develop the way it provides access to advice and information about its products and services, including the role of appointment based face-to-face advice.

Doorstep selling, in its current form, is an increasingly outdated way for energy companies to engage new customers who no longer regard it as a preferred or trusted way to review their energy arrangements.

British Gas has been reducing the use of doorstep selling for many years. The number of British Gas field sales agents is now less than a quarter of the 1,300 employed in 2006.

Adam Scorer, Director of External Affairs at Consumer Focus, said:

‘British Gas has responded to our call for action. We applaud the move and call for others to follow the lead set by British Gas and SSE. This is the sort of move that responsible companies make when it becomes clear that consumers are unhappy with the way they do business.

‘For over a decade cold call doorstep sales have led to hundreds of thousands of people paying more for their energy after switching to a worse deal. We know people strongly dislike doorstep sales, feel pressured to switch at the door and that energy firms don’t offer their best rates face-to-face. Cold call energy sales simply aren’t what customers need or want.

‘Energy firms have had years to get doorstep sales right. There have been plenty of well-intentioned commitments and initiatives to do things better, but they have failed to deliver the change that consumers want.2 Unless other energy firms realise the end of the road has been reached on cold call doorstep sales, mis-selling will continue to drive consumer mistrust even deeper. It also risks damaging consumer confidence and buy-in for key Government schemes, including the Green Deal and smart meter roll-out.

‘We would urge all consumers to think twice before they buy on the doorstep, shop around for the best deal, and take time to think things over before making a final decision.’

But British Gas seems to be reserving the right to resume such activity, if its competitors persevere with it.

The fact is, door to door utility salespersons have been scamming people across Britain for years, with many of them working for unscrupulous ‘marketing’ firms hired by the energy suppliers. It’s outrageous that they are allowed to call at the homes of confused old people, and sign them over to more expensive contracts.

Consumer Focus suggests that all consumers ‘shop around for the best deal’, but this is much easier said than done. The utilities companies have a plethora of different and complex tariffs, and equally complex terms and conditions. This makes the comparison of suppliers’ offers an extremely difficult task, probably beyond the capabilities of most people. So there needs to be a substantial amount of imposed tariff standardisation, in order that people can make informed choices between different suppliers’ quotes on the same product.

Written by beleben

August 12, 2011 at 8:24 pm