Making Britain’s railway ‘greener’

Global warming, the environment, carbon emissions and the reduction of greenhouse gases are at the centre of the political and environmental agenda both in Britain and the wider European Union. At the end of the Brussels European Council of 8/9 March 2007, the EU Presidency committed itself by commenting that; “The EU makes a firm independent commitment to achieve at least a 20% reduction of greenhouse gas emissions by 2020 compared to 1990.” The need to find greener solutions has become even more urgent as the price of oil nears $100 a barrel, and it has become accepted as good business practice for industries to find greener more efficient fuels and more environmentally ways of operating.

The challenge set down by the European Union has been grasped by CER and UIC, on behalf of all European railways, and will seek to ensure that rail places its part in achieving this 20% greenhouse gas (GHG) reduction by 2020 by developing a coherent and transparent ‘roadmap’ for rail.

Rail has a head start as it is perceived as one of the most environmentally friendly mode of mechanised transport, as can be seen from the Environment Baseline Statement published earlier this year by the Association of Train Operating Companies (ATOC).

The ATOC study shows that in the UK, rail travel broadly generates a little over half the emissions per passenger kilometre of car travel and approximately one quarter of that of domestic air travel. This will of course vary from country to country, depending on factors such as energy and fleet mix.

However, ATOC believes that rail cannot afford to be complacent and stand still, as competitors, such as the car industry are already developing a car ‘glide path’ taking the current 130 grams per kilometre down to less than 40 grams per kilometre. Japanese manufacturers are moving on from hybrids to volume production of hydrogen cars in the near future.

Rail must therefore play its part in maximising the ‘quick environmental wins’ by promoting the merits of modal shift. At the same time, Rail must modernise, adapt and harness new technologies to ensure that its share of carbon emissions and other pollutants are reduced.

So what is rail in the UK doing to improve its own environmental credentials? Environmental and concern about the cost of energy consumption has spurred a huge effort over the last two years by ATOC and its members to improve its understanding of how energy is used in rail traction.

ATOC is participating in European Groups such as the CER and the UIC Sustainability Groups. Projects such as the RailEnergy project has shown that issues and solutions don’t stop at borders and good practice is good practice wherever it is found.

ATOC’s Engineering Council, with a steering group of TOCs, Engineering and Fleet Directors have also commissioned best practice groups, embracing areas such as emissions, metering, hotel loads, regeneration and operations.

There are three core work streams that the ATOC cross-industry environmental improvement programmes are currently focusing on, which are; emissions, energy efficiency programmes and operational performance.

Emissions

Various European and national directives have created an exciting playing field for the UK rail industry. In Britain, 40% of the train fleet is diesel and uses gasoil, which currently has a sulphur content of around 1,500 ppm. However, recent and proposed directives will reduce the sulphur content to less than 1,000 in 2008 and then 10ppm (i.e. Sulphur Free Diesel (SFD)) from about 2010.

Following the award-winning ATOC-led SFD programme in 2006, work is now underway to enable the railways to trial SFD blended with biodiesel, which will not only improve rail’s sulphur dioxide emissions, but also reduce the overall ‘carbon footprint’. The process being followed is shown in the following table:

This €1.5 million cross-industry research programme, led by ATOC and the Rail Safety Standards Board (RSSB) in conjunction with train operating companies, freight operating companies, rolling stock leasing companies (ROSCOs) and the Department of Transport (DfT), is known collectively as the Biodiesel Working Group.

This Biodiesel programme is currently progressing from bench-testing which involves the testing of SFD with varying amounts (5% to 50% plus) of ‘bio’ using seed-based oils, such as rape seed, in a variety of train engines (5 engines, covering 80% of Britain’s diesel fleets) through to service trials. The first in-service biodiesel trials commenced on Virgin CrossCountry in June 2007, using a Cummins QSK-19 diesel engine on the Voyager fleet.

The Biodiesel Working Group is currently assessing the feasibility of service trials with the Cummins NT855 and also a Perkins engine, which are currently used on regional services across the country. These service trials will look at the long term technical and operational effects caused by biodiesel blends. Assuming the trials are successful, they should lead to the roll-out of these initiatives during the next 2-3 years. The exact blend is still to be defined, but an initial 5% to 10% range is probably realistic.

One caveat, that does need careful consideration, which has recently been extolled by Environmental NGOs (inc. WWF, Greenpeace and Friends of the Earth) in May 2007, was their comment that, “A misjudged push for the wrong kinds of ‘green’ fuels could damage the climate and destroy the world’s last remaining rain forests”.

Their concern is related to the potential impacts of growing crops for biofuels on,

• Competition with food
• Biodiversity (e.g. forest clearance)
• Water and soil resources
• Greenhouse gas balance

The need for a robust European Biodiesel certification scheme to address these issues was strongly highlighted in the ATOC Biofuel report for UIC in June 2007.

Complicating the equation further is the Non Road Mobile Machinery (NRMM) Directive 2004/26/EC which sets quite stringent ‘local’ emission limits onto the market, with Stage 111A in force from 2006. Although, there is a technical review underway in 2007, 111B can be expected to come in force in 2012 and currently this will likely require technology that has not been utilized in the Rail industry, such as Selective Catalytic Reduction (SCR) or Exhaust Gas Recirculation. Apart from the reliability of the new technology, there will be issues related to size, weight, increased fuel consumption and indeed, as the Railway Diesel Study commissioned in 2006 by the European Commission, asked whether it will deliver an ‘overall net benefit’.

Energy efficiency programmes

The cost and environmental consequences of energy consumption has spurred a huge effort over the last two years by ATOC and its member companies to improve its understanding of how energy is used in rail traction.

When energy started to become a ‘hot topic’, and stakeholders began asking searching questions, investigation showed that many of the published figures depended heavily on modelled results. The assumptions in the models were not always clear and the figures were open to challenge.

In 2006, a major study was undertaken on three fleets in the UK:

• Class 222 trains on the Midland Mainline diesel inter-city route
• Regional diesel services in East Anglia with Class 170 units
• Class 357 trains on the London Tilbury and Southend 25kV electrified commuter line

Methodology developed by Bombardier and the Royal Technical School in Stockholm (KTH) for trains in Scandinavia was used, allowing for credible international comparison. The resulting report₁ gave some firm and reliable data on energy use and CO2 emissions for the first time. This has since been widened into a summary for all UK passenger services in the ATOC Baseline Report₂.

The report started to show where all the energy was going with disturbing amounts disappearing on ‘hotel’ heating and lighting, particularly for commuter trains (over 20% of the total) which spend lengthy spells in the sidings between rush-hour trips. Also, the considerable energy demand for the high acceleration and frequent stops from full line speed (175kph) on the Midland route was exposed. Duty cycle is in fact a major determinant of energy consumption, meaning that comparisons between train fleets have to be made with care to be sure that like is being truly compared with like.

The level of interest aroused, and the opportunities suggested for energy saving if consumption was more closely monitored, has led to the first fitment in Britain of a remote reading energy meter certified to electrical supply industry standards. This follows the lead set by various European countries, notably Germany, Slovenia and the Nordic group.

The fitment of two such meters, one to each of the transformer cars on Virgin Pendolino set 390 049 was completed in August and the results are now being analyzed. As well as proving the integrity of the system, the trial is giving a detailed picture of how energy is used, service by service, on the Virgin network. This will allow evaluation of energy saving strategies such as berthing load management and so-called ‘eco-driving’. Also, the meters are confirming the value of the regenerative braking on the Pendolino sets, showing that the target energy saving of 16.5% is being realised.

Regenerative braking is the single biggest ‘technical hit’ for energy saving with electric traction. The original 2006 study on the Southend line was done before regeneration was commissioned on this route. This gave an ideal opportunity for a ‘before and after’ analysis and when this was done, the results were most encouraging. Measured at the feeder stations (the Southend line is a closed network with very little other traffic, making measurement straightforward) savings over 20% on total fleet consumption were proven between June 2006 and the identical period in 2007 – this despite the high proportion of auxiliary load on trains on this line.

Energy metering trials are now being rolled out by operators on other routes, following the maxim, ‘If you can’t measure it, you can’t manage it’! Management is in fact the critical point. Experience in Britain and elsewhere shows that the ‘people factor’, motivating energy saving, monitoring progress and celebrating success, is often just as important as technical innovation – and without attention to the human element, the purely technical initiatives may yield only meagre results.

Performance

Studies carried out by ATOC show that the smooth running of a train has a significant impact on energy consumption. Again, work is on-going in a number of areas including:

• ‘Smooth’ driving performance, be it driving techniques, utilizing simulators or somewhat further in the future, better information for the driver, advising them on how they ‘need’ to drive. The former, was an area that the recent UIC Energy conference in Slovenia highlighted as a potential for ‘quick wins’
• Ongoing work by ATOC’s Engineering Council and their National Fleet Reliability Improvement Programme group, which seeks to allow the industry to trade best practice on managing and improving train fleets reliability
• Working with Network Rail and FOCs to improve traffic regulation

So in conclusion, it is ATOC’s view that while the railways can’t replace the car, Britain will meet its environmental objectives more readily if rail carries a greater share of national traffic. To do that, rail cannot be complacent of its current ‘green’ credentials and it is hoped that the above is but a ‘taster’ of the programmes that ATOC and its partners in the UK and with CER and UIC, are undertaking to ensure that rail is playing its part for the future of environment, for the passenger and the businesses involved.

References

1. The Energy Consumption of Rail Vehicles in Britain, Hinde and Larsson, ATOC, 2006
2. Baseline Energy Statement, ATOC, 2007

About the author

Ian Papworth

Ian Papworth is ATOC’s Engineering Director and leads a team that looks after TOC engineering interests in sectors such as rolling stock standards, reliability and performance, supplier development, sustainability and the environment. He is a member of Standard interface Committees and Technical Strategy Advisory Group. Apart from being a member of various CER and UIC groups, he is also Chair of the Carbon Working Group and Railway Industry Supplier Approval Scheme (RISAS).