Today, more and more travelers are interested in the CO2 emissions of their trips. A special interest is sailing on a ship carrying both cargo and passengers. However, the traveller receives very different answers about one’s share of emissions. Some sources show that water transport is very environmentally friendly and others that it is actually very polluting. This is because different sources use different calculation methods.
When a ship carries both cargo and passengers at the same time, a decision must be made in the determination of unit emissions as to which part of the vehicle’s emissions is calculated (allocated) to the cargo and which part to the passengers. Well over 90% of the world’s cargo is transported by cargo ships with no passengers at all. More than 85% of Finland’s foreign trade at sea is carried out by ships with no passengers at all. On the other hand, passenger car ferries to Stockholm and Tallinn carry millions of passengers a year.
Finnish research institute VTT says that at least 19 different allocation methods can be presented and none is seamless. The European Union’s MRV standard and the Finnish Standard SF-EN 16258 provide two options: allocation in terms of the weight of passengers and cargo; and allocation in terms of space reserved for passengers and cargo on board. The difference between the two can be as much as 70%.
Emissions calculated according to the European Union’s MRV standard, which are therefore allocated by weight, can be viewed here: https://mrv.emsa.europa.eu/#public/emission-report. On the other hand, VTT has come up with a solution in which the unit’s emission pages use allocation on the ship in terms of space reserved for passengers and cargo. They can be viewed here: http://lipasto.vtt.fi/yksikkopaastot/info_vesi.htm
In my opinion, emissions should be allocated in terms of turnover, i.e. the more cargo or passengers the ship produces, the higher the share of emissions – this is therefore neither of the above options. After all, a ship has its customers in traffic who pay for the transport of themselves or their products, and however, the choice of ship type always ultimately depends on whether it generates a return for its owner. In practice, however, the most important thing is that each mode of transport and each shipping company reduces its emissions compared to the past. In other words, it is worth choosing a shipping company that is committed to reducing emissions and using environmentally friendly technology, as well as promoting the use of new, low-emission maritime transport. How to do this in practice can be read from my previous column: https://ullatapaninen.net/2021/06/18/imo-decided-the-key-mandatory-measures-to-reduce-ships-carbon-intensity/