The envirionmental impact of ship traffic - fewer emissions with low-sulphur fuels

In most cases, their large marine diesel engines are driven by heavy fuel oil, which contains up to 4.5 percent sulphur. The resulting harmful emissions cause an unwanted burden on both the environment and human beings, especially in densely populated coastal regions and ports. In 2011, DLR researchers from the Institute of Atmospheric Physics in Oberpfaffenhofen analysed how alternative fuels could help solve this problem. Building on experience from the long-standing project “SeaKLIM, Impact of Shipping on the Atmosphere and Climate”, Dr. Veronika Eyring and her colleagues examined how the environmental impact could be lessened by switching to biofuels or so-called marine diesel oil with a lower sulphur content. Using cargo shipping data and sophisticated computer models, the researchers simulated the exhaust pollution in the atmosphere. One important finding was that sulphate aerosol concentrations could be cut by up to 60 percent along busy sea routes if heavy fuel oil was no longer used. The pollution caused by soot and sulphur dioxide could also be reduced but the level of emitted carbon monoxide and nitrogen oxides would largely remain the same. Studies like this provide an important basis for the more stringent emission regulations that are currently being discussed for global shipping. For the period 2020–2025, the International Maritime Organization (IMO) aims to gradually introduce lower limits, particularly for the sulphur in fuels. Europe is a pioneer in this field. Beginning on 1 July 2010, ships travelling in the special emissions area in the North and Baltic Seas have been subject to a 1 percent limit on sulphur in fuel and ship emissions.

Jan Oliver Löfken