Renfe has conducted the first pilot test of railway traction with liquefied natural gas (LNG) in Europe, and the first in the world in the passenger rail sector, on a 4 km stretch of a metre gauge suburban line in Asturias, in the north of Spain.
The objective of the project, led by Renfe together with Gas Natural Fenosa and Enagás and in collaboration with Bureau Veritas, is to verify the viability of an alternative solution to the traffic currently being developed with diesel traction.
The project is part of the decarbonisation and energy efficiency plan in which Renfe and Adif are working and the strategy to promote the Vehicle with Alternative Energies in Spain 2014-2020.
The tests are conducted in a self-propelled train of the Feve diesel fleet, 2600 series. The diesel engine of one of the two paired automotive units has been replaced by another one that consumes natural gas for its propulsion, and the tanks in which the LNG will be stored together with the necessary auxiliary elements have been installed.
Traffic will allow contrasting the results obtained, both for diesel and gas technology, since a tractor unit is maintained with each type of fuel in the same train.
From these tests conclusions will be drawn about the technical requirements of space, weight, refrigeration and autonomy for the traction of natural gas, in addition to other considerations and comparative variables in emissions and operating economy.
From the environmental point of view, the main advantages of the use of natural gas as a railway fuel are the decrease in pollution by reducing emissions of nitrogen and sulphur oxides, particulate matter and carbon monoxide, noise pollution and greenhouse gases, as well as opening options in the face of possible new environmental demands in the railway sector.
From the economic point of view, it provides a better general price scenario with respect to petroleum fuels and the reduction of the energy dependence of this source, while it also offers an alternative to investment in electrification of non-electrified sections.