To be able to make a correct comparison of the environmental impact of various forms of traffic, it is necessary to look at the entire life cycle, where infrastructure is an important component. From that perspective, the environmental benefits of travel by rail compared to road traffic are not as great as we often imagine, according to Niclas Svensson Environmental Technology and Management at Linköping University.
“The environmental work done by Banverket, the authority that manages Sweden’s rail network, has been limited to local and regional problems like weed control along the banks and creosote in ties. Global issues like energy use and carbon dioxide emissions from the production of railroad materials have not been in focus to the same extent,” says doctoral candidate Niclas Svensson.
If you factor in infrastructure and operations, buses can be the most economical alternative for travelers today in terms of energy use. A trip on a train powered by electricity costs one third more in energy terms, but results in lower net emissions of carbon dioxide. If the train is powered by diesel, it is a considerably worse than a bus in both respects.
However, the results of a comparison of various modes of transport are highly dependent on how much of their full capacity is actually used. In trunk lines, in computer traffic around major cities, and for freight, rail transport is still more energy efficient.
Above all, what makes railroad construction such a heavy consumer of energy is the steel used in rails. Since such huge quantities are needed, and so much energy is required for its production, steel is the most important product for Banverket’s environmental efforts.
“Energy use can differ by as much as 50 percent at different steelworks. Banverket should require more environmentally friendly production in its procurement of steel,” says Niclas Svensson.
The life-cycle analysis applied in the dissertation is based on data from the construction of new dual tracks for commuter traffic between Stockholm and two suburbs.
For 6.9 kilometers of track, nearly 900 tons of material was used, of which 94 percent was gravel, 4 percent concrete, and 2 percent steel. However, in terms of energy use, the steel accounted for 77 percent, the gravel 9 percent, and the concrete 4 percent.
The dissertation, Life Cycle Considerations for Environmental Management of the Swedish Railway Structure, will be publicly defended at Linköping University on Friday, December 15, at 1:15 p.m. The external examiner will be Associate Professor Tomas Kåberger.