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Friday, 13 January 2012

The Environmental Account of Rail Travel

Dirty Pleasure

‘Murder on the Orient Express’, ‘Some Like it Hot’, ‘The Lady Vanishes’ – some of the greatest movies featured trains as settings for romance, mischief and mystery. No wonder, the confinement of the enclosed space while thundering along adds a sense of inescapability and tension. Accompany that with a steam engine and it’s heaven for those with a fondness for nostalgia.

Sadly, the reverie stops – for the environmentally minded at least – as soon as one realises that this dream was running on fossil fuel. Something needed to burn for the water to boil. Without it the wheels didn’t turn. Usually, that fuel was coal. Even before pollution became a fashionable subject steam engines were derided for the lack of clean air credentials. I remember my grandmother telling me that hanging out the washing was closely linked to the wind direction when they lived near a busy rail centre or the whites were speckled with soot.

Steam Train 1

The Green Train

How things have changed. Nowadays, the train is regarded as a pillar of public transport, which itself has taken on the generalised air of responsible travel. While car and airplane are accused of being ghastly polluters, moving along on rails seems to have become the darling of the environmentally conscious.

Eurostar underlined that with a study they commissioned. On the website they stress: “[The research]…uses detailed data on electricity supplies, power station emissions and transmission losses; Eurostar and airline load factors; and the range of aircraft and engine types and emissions.
The figures are the most detailed ever produced and are based on actual passenger numbers, exact distances of rail and air routes, actual aircraft types in use on different routes, and the mix of electricity sources..
.” Apparently, the train emits only 6.5% - 8.9% of the carbon dioxide (CO2) a plane would produce on the same route. That is impressive to say the least, and the company proudly headlines the results (an example of which is below) with The Green Eurostar.

CO2 Comparison  Eurostar - Plane

These figures have been picked up readily by other rail-orientated organisations and individuals, such as InternationalRail or Mark Smith, the famous Man in Seat Sixty-One.

Caution – Not all-inclusive

CO2 is not Everything

So, there you have it. If you want to travel and save the planet all you have to do is take the train – until you view it from a different angle.

All these reports, opinions and recommendations rest solely on CO2, but reducing that particular greenhouse gas alone does not make everything environmentally friendly by default. Going back to Eurostar, what the company and those using the results of their study fail to mention is a small but important detail. The trains run only a relatively short distance in the UK or Belgium. The main parts of their journeys go through France, which means also that this is where they draw electricity for most of the time. Only, according to the World Nuclear Association 75% of all power generated in that country is nuclear energy. Call me picky but in my eyes that is neither environmentally friendly nor renewable.


The other problem with taking the assertions at face value that train travel is better for the environment full stop is they all rest on assumptions or data valid for electric propulsion. Unfortunately, only part of the world’s network is electrified, as can be seen from the figures below.

 Rail Electrification in Europe and America
While steam still exists in a few remote corners around the globe the remainder is covered by diesel engines. A BBC report speaks of six tonnes of fuel a locomotive has to carry and eight miles to the gallon. Mind you when considering that a British intercity engine weighs the best part of 70 tonnes, not to mention carriages, passengers, luggage and whatever else, fuel consumption of such calibre doesn’t look that bad anymore. In addition one has to consider every gallon of fuel is used not by a just couple of people but potentially hundreds. Nevertheless, that translates into almost 19 tons of CO2 by the time the fuel gauge reaches ‘Empty’.

The Other Side of the Coin

What comes out of the exhaust is never the whole story, though. It is a long way from raw material to greenhouse gas, with many elements in between. As I explained in a previous article on biodiesel, to take them all into account it needs a life cycle assessment. It measures the full environmental impact from cradle to grave.

Mikhail Chester and Arpad Horvath of the Department of Civil and Environmental Engineering, at the University of California, Berkeley, USA explain it as “…including both the direct and indirect processes and services required to operate the vehicle. This includes raw materials extraction, manufacturing, construction, operation, maintenance, and end of life of vehicles, infrastructure, and fuels.” Such comprehensive research can have surprising results. In 2009 they published a study that they had conducted investigating and comparing cars, pick-ups, buses, trains (electric and diesel), as well as aircraft. Components they looked at ranged from cold start of an engine to runway construction, from escalators to fuel refining and distribution

Their results showed emissions additional to those found if just measured at the point of use. For motor vehicles it was +63%, +155% for trains, and +31% for planes. All of a sudden air travel faired not much worse than rail, especially since they also looked at other pollutants than CO2, like sulphur oxides or nitrous oxides.

What became quite clear was that the numbers of passengers, i.e. occupancy rates, were a decisive factor. A full aircraft might be less polluting than a train with travellers in only a third of the seats. That is something Fred Pearce at The Guardian demonstrated in his article Greenwash: Time for rail to raise its game and cut emissions.


Is Rail Travel Environmentally Side-lined?

Of course not. This is not a diatribe against trains but a reminder that there is no perfect solution to our energy concerns. Figures are habitually used in ways that support the view or purpose of those who want to make a point. Rail travel just isn’t the clean, green miracle as which it is often portrayed but at the same time it is the best choice for many situations, since everything else is worse.

New Technology Pushes Trains to the Top of the League

As a review by the British Department for Transport says, Rail’s environmental advantage has […] reduced and will continue to do so unless action is taken.” Particularly in Europe cars and lorries (trucks) have become far more efficient and new systems, for example hydrogen fuel cells or hybrids, will reduce their impact dramatically even in the near future. However, trains will benefit from the same technology. Some are running already with regenerative brakes that produce energy during deceleration. Use of bio fuels, re-configuring older stock with hybrid engines and other measures are either in the planning stages or being implemented.

Here in Europe there is much more of a case for rail travel anyway, because of the relatively expansive electrification and the advances in renewable energy provision. However, others are catching up. China has rekindled its love affair with high speed links, despite escalating costs and horrendous disasters. While it is the world’s largest producer of greenhouse gases it is also fast becoming the biggest market for clean energy like solar power. At least part of it will go into propelling futuristic trains that hurtle along at over 200 miles per hour (320 km/h).

The point where Chester’s and Horvath’s research deviated from the conditions in Europe was the continued massive use of fossil fuel in America, which caused cars and buses to end up at the tail end but also disadvantaged rail with its negligible use of electric power there. If all goes well, this is not to stay that way. An improved network is the focus of the administration’s transport policy together with boosting renewable sources.

Sunny Stations

The infrastructure that the two scientists said must be incorporated into the study material is not exempt. Blackfriars station in London, Britain, is being renovated and upgraded. Amongst the new features are 4,400 solar panels that will provide 50% of the station’s energy needs. Belgium has gone several steps further and covered an entire tunnel near Antwerp in photovoltaic panels. The 50,000 m² installation is expected to generate 3,300 MWh and will power, for example, signals and heating. Here too China features prominently with similarly equipped stations there.

A Case for Romance

Travelling by rail is an excellent way to get from A to B. It is not as practical, cheap or clean as many of its supporters are trying to tell us - at least not yet - but in many situations it is the best overall choice.

Away from practicalities and realism my dream journey is pure self-indulgence and admittedly non-renewable. It would be the trip of a lifetime with the Pullman from London to Paris and then onwards to Venice on the Orient Express, both pulled by great, big steam engines. I know it is hypocritical with all that smoke and CO2, but sometimes there is a case for romance and quite honestly I would shovel the dirty old fossil coal myself if necessary. Mind you, there were steam engines converted to running on oil, so why not bio fuel (from waste, naturally)? Now that got me thinking …


“I have found out that there ain't no surer way to find out whether you like people or hate them than to travel with them".
Mark Twain


See you next week


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