How maximising the service life of trains helps reduce the rail industry’s carbon footprint

The Government’s Budget was always going to be overshadowed by the COVID-19 pandemic, given the seriousness and the scale of the challenge at hand. However, Rishi Sunak still found time and space to talk about another, longer-term challenge that will persist even after normality resumes - climate change. The UK Chancellor announced measures to cut taxes on electricity and increase them on polluting gas. He also pledged to double research and development in energy research.

Trains have long been regarded as one of the greenest modes of transport, but the rail industry is not sitting idle when it comes to reducing its carbon footprint ever further. Most people understand that diesel engines make carbon dioxide and electric trains do not, but it is less well known that a large proportion of the carbon emissions are associated with the initial manufacture of trains. Maximising the service life of existing rolling stock- and avoiding scrapping trains prematurely - helps save unnecessary carbon emissions.

Looking at carbon emissions associated with a train over its 30-35 lifetime, the point of manufacture accounts for twice as many carbon emissions as for the vehicle’s ongoing maintenance. According to the findings of an independent study in 2011 by the RSSB, the manufacture of a new electric train produces the equivalent of 146 tonnes of CO₂, while its maintenance accounts for little more than 2.3 tonnes CO₂ per year.[1]If rolling stock is used for its full service life (and not scrapped prematurely), the emissions associated with its manufacture are deferred significantly.

Of course, the operation of a train also generates emissions, so we also need sustainable, green energy to electrify the railways. OFGEM data shows that over 25% of Britain’s electricity is generated from renewable, non-carbon emitting sources – but the use of sustainable energy sources is expected to increase dramatically, eventually making the operation of electric trains completely carbon neutral.

But what about routes where self-powered trains are needed? Porterbrook is investing in new technologies such as battery powered trains, hybrid technology and hydrogen power as a solution to this issue. These new can be retrofitted to existing trains - diesel trains, can be fitted with a battery pack to allow for quieter, cleaner operation in urban areas, and electric trains can be fitted with hydrogen technology to run on non-electrified routes.

Brand new electric trains are still needed when existing rolling stock reaches the end of its life. New manufacturing methods and changes in energy generation will eventually reduce the carbon impact of operating these trains, but in the meantime the UK needs immediate practical solutions that deliver lower carbon and reduced emissions.

[1] RSSB (2011). Whole Life Carbon Footprint of the Rail Industry (T913). RSSB.