‘Just-in-time’ Sailing Saves Hundreds of Thousands of Tonnes of CO2
If sea-going vessels were better informed about the availability of berths and adapted their speed accordingly, substantial savings could be made in terms of fuel and CO2 emissions. This conclusion is based on a study that was recently commissioned by the Port of Rotterdam Authority and research institute TNO.
If sea-going vessels are regularly kept informed – particularly during the last twelve hours before arrival – about exactly when their berth will become available, they will be able to adapt their sailing speed accordingly. That usually means reducing their speed so that they arrive just in time. This in turn leads to less fuel consumption and therefore lower emissions of unwanted substances such as carbon dioxide, sulphur oxides and nitrous oxides. Significant savings are also possible thanks to shorter waiting times for ships in anchorage areas.
The wallets of the shipping companies
The results of the study were presented this week at the head office of the International Maritime Organisation (IMO) in London during a meeting of the IMO Inter-sessional working group on the reduction of Greenhouse Gas emissions from ships. “In percentage terms, we’re talking about modest amounts,” says Astrid Dispert, Technical Adviser of the GloMEEP Project (Global Maritime Energy Efficiency Partnerships). “But it’s exactly these types of measures that can make a huge difference in the short term and help reduce the carbon footprint of marine shipping. Added to that, they’d also have a beneficial effect on the wallets of the shipping companies.”
5% adjustment in sailing time
TNO and the Port of Rotterdam Authority, which is a member of the ‘Global Industry Alliance to support low carbon shipping’, analysed all the movements of container ships sailing to Rotterdam port in 2017. “By supplying more accurate information to ships, 4% – or 134,000t – of CO2 emissions can be saved every year,” explains Jan Hulskotte, Senior Researcher at TNO. ‘To do this, container ships would have to adjust their sailing speed by an average of 5 percent, and still arrive at the planned arrival time.’ And even more savings could be made if ships were better informed more than twelve hours before arrival.
Anchorage areas: even greater savings
The study also examined the impact of shorter waiting times in anchorage areas for all ships sailing to Rotterdam. In the bulk transport sector, ships sometimes have to wait at anchor for hours or even days; this is mainly due to contractual obligations. Mr Hulskotte, “If this waiting time was an average of 12 hours shorter, that would really make a difference in percentage terms, with an annual reduction of 35% in emissions. So we’re talking about 188,000t of CO2 and 1,000t of nitrous oxides.”