Eight out of every ten ships meet the northern European rules on sulphur

Emissions of sulphur from shipping fell sharply when the tightened EU rules came into effect at the start of the year. This is shown by recent measurements by researchers at Chalmers University of Technology, at the entrance to Gothenburg Harbour in Sweden. But not all shipping lines appear to be complying with new stricter emission requirements.

It is estimated that 50 000 Europeans every year die because of poor air quality caused by the bunker oil with a high sulphur content that is used as a fuel in shipping.

But improvements are now on the way. The maximum permitted level of sulphur for vessels sailing in northern European waters was radically reduced at the start of the year, from 1 percent to 0.1 percent.

Ever since 2006, researchers Chalmers University of Technology have been working on the development of a new method to monitor emissions from shipping in an effective way, without needing to carry out time-consuming inspections on board.

The unique technique has been used for four years in trials at a measuring station located at the fortress of Nya Älvsborg, next to the channel leading into Gothenburg Harbour on the Swedish west coast. Emissions from passing ships are recorded and analysed there continuously.

The measurements are now showing that sulphur emissions fell by around 80 percent when the rules came into effect.

During the first two weeks of the year nearly 200 ship passes were analysed, and nearly half of these complied with the new limit value of 0.1 percent.

"Emissions just above the limit were observed for many ships, so given that there is some uncertainty in the measuring method at least 80 percent of ships can be considered to be approved," Johan Mellqvist, professor of optical remote sensing at Chalmers, explains.

This can be compared with the previous four years, when emissions on average were at a level equivalent to a fuel sulphur content of 0.6–0.7 percent.

But the initial measurements for the year also point to fairly wide spread among those ships that do not meet the emission requirements, and this is something that Johan Mellqvist and his colleagues will now be looking at more closely.

Reducing sulphur emissions costs shipping lines large sums of money, regardless how they choose to meet the requirements.

There are various alternatives:

• Either follow the letter of the law and operate ships with the significantly more expensive, low-sulphur bunker oil.
• Or install treatment equipment on board so that sulphur emissions decrease to an equivalent degree.
• A third option is to switch to a completely different fuel, for example liquefied natural gas (LNG) or methanol, which the ferry company Stena Line is now testing on some of its ships.

The shipping lines have not been universally in favour of the tightened emission rules.

But now that they have been introduced there is strong pressure from the industry for the rules to be enforced and for those who contravene them to be prosecuted by the authorities.

"There is concern among established shipping lines about their competitors cheating and gaining a financial advantage," says Chalmers researcher Jörg Beecken, who recently defended his doctoral thesis on the method of measurement he has developed together with research colleagues.

The method is based on a combination of several established techniques and can be used both for fixed measuring stations on the shore, as at the fortress of Älvsborg, and for measurements from aircraft.

Chalmers has also installed and tested its equipment in a Danish aircraft, which is now ready for routine monitoring.

"Aerial measurements are becoming important, as they are the only way of checking emissions when the ships are at sea," Johan Mellqvist points out.

Chalmers recently held a workshop on the new technique for emission measurements, with representatives from shipping authorities and researchers from several European countries, where the updated measurement data from Gothenburg Harbour was presented.

Caption: Emissions from shipping are monitored by chemical analysis, using a “sniffer” at the fortress of Nya Älvsborg, next to the channel leading into Gothenburg Harbour.

More about the technology

The method developed by the researchers at Chalmers is based on a combination of established techniques, which have been refined and adapted to their purpose, such as optical remote sensing, chemical analysis using a "sniffer" and monitoring of ships by AIS (automatic identification system).

As well as sulphur, the system can analyse ship emissions of nitrogen oxides and particulates – pollutants that are also expected to be subject to tightened rules.

More about sulphur emissions

Sulphur emissions are primarily a health issue, but in the Nordic region emissions also contribute to the acidification of lakes and rivers, due to the lime-poor bedrock.

The new tightened rules form 1 January this year also cover the Baltic Sea, Kattegatt, Skagerrak, North Sea and English Channel.

The rest of the EU follows the rules adopted by the UN's International Maritime Organisation (IMO).

This means that the maximum sulphur level in the fuel will be reduced in 2020 from the present-day level of 3.5 percent to 0.5 percent.

For more information, please contact:
Johan Mellqvist, professor of optical remote sensing, Chalmers University of Technology, Sweden, tel +46 703-088777, johan.mellqvist@chalmers.se

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