Researchers: Illegal nitrogen emissions from ships in Swedish waters

Nitrogen oxide smoke from ships is harmful to health and inhibits climate emissions and nutrients.

– A number of people die early or develop asthma, says Professor Johan Melqvist in Chalmers.

Many vessels more than double the cut-off values

Researchers in the European Union project master He measured nitrogen oxide emissions from 65 so-called Level III ships. They are manufactured from 2021 and must comply with the new rules. The measurements were made via static air gauges when the ships passed the Great Belt Bridge in Denmark and off Rotterdam and Hamburg, but also with the help of aircraft and drones.

remote sensing method of nitrogen oxide emissions are not perfect, they can measure errors between 17 and 40 percent, but since many ships were more than twice as high as their maximum values, one can still be sure that many of them were breaking the rules, Johan Melkvist believes.

The same type of cleaning as on land diesel vehicles is required

– It can be cheating to ignore the so-called urea injection because you think it costs too much, says Johan Melqvist.

To reduce nitrogen oxides in the boat’s exhaust, a purification fluid is added that converts it into harmless nitrogen and water vapor. Similar technology exists in diesel vehicles on land (Adblue).

Nitrogen emissions from boat engines are tested at the factory under ideal conditions. According to Johan Melqvist, there is a risk of something similar to a “dieseljet”, where Volkswagen cheated by cleaning the catalyst while driving.

The Swedish Transport Agency wants to investigate the shipment of nitrogen oxide to ships

The Swedish Transport Agency is responsible for ensuring that ships operating in Swedish waters comply with emissions regulations.

– It is difficult to achieve the environmental goal of reducing nitrogen emissions, so we would like to investigate, for example, nitrogen emission charges for ship traffic, says Caroline Petrini, environment officer at the Swedish Transport Agency.

Learn more about the Swedish Transport Agency’s proposal on how to better control ships in the video above.