This study is an update of the original STREAM study published in 2008. There is also an update 2020. It provides a comprehensive review of vehicle-based freight transport emissions per tonne-kilometre for the various market segments of international freight carriage. The report also compares tonne-kilometre emissions based on average vehicle technology (average age) and average load factors in various scenarios, including substantial modal shifts in the coming decade. In the calculations due allowance has been made for upstream and downstream transport.
The scale of transport is of crucial importance for emissions. In addition, load factors and other logistical issues also play a key role. Which mode of transport is ‘greenest’ differs from situation to situation, depending on the type of emissions considered. Electric rail transport remains a very clean and efficient form of transport.
The main focus of the study was on emissions of the greenhouse gas carbon dioxide (CO2) and air pollutants like particulates (PM) and oxides of nitrogen (NOx) and sulphur (SOx). The study was carried out on a commission from the Dutch Ministry of Infrastructure and the Environment.