Researchers at Chalmers University of Technology have shown that between 87 and 98 percent of ships comply with the tougher regulations for sulfur emissions that were introduced in northern Europe in 2015. The lowest levels of compliance were observed in the western part of the English Channel and in the middle of the Baltic Sea.
The highest permitted sulfur content in shipping fuel was sharply reduced at the end of 2014 for vessels sailing in the northern European sulfur Emission Control Area (SECA) from 1.00% (10,000 ppm) to 0.10% (1,000 ppm). Before the stricter regulations were implemented, sulfur emissions from the shipping industry were estimated to cause the premature death of 50,000 Europeans each year, because the sulfur forms particles that are swept inland by the wind.
Researchers at Chalmers University of Technology, Sweden, have developed a method for remotely monitoring emissions from marine vessels, which they’ve used to investigate the effects of the new regulations. The work has been carried out through the Danish Environmental Protection Agency and the EU projects Compmon and Envisum.
The method that the Chalmers researchers have developed is based on a combination of established technologies that have been refined and adapted. They include optical remote sensing, physical/chemical analysis using a “sniffer” and monitoring vessels using an Automatic Identification System (AIS). In addition to sulfur, the system can analyze marine emissions of nitrogen oxides and particles, for which the regulations have also been tightened for the shipping industry in recent years.
Some of the measurements were taken using an airplane flying over Denmark, the English Channel and the middle of the Baltic Sea, while others used fixed measuring stations in the approach to Gothenburg, Sweden, on the Oresund Bridge (between Copenhagen and Malmo) and on the Great Belt Bridge in central Denmark.
Johan Mellqvist, professor of optical remote sensing, who heads the work at Chalmers, said that differences in how the regulations are followed depending on who owns the vessels. While the vast majority of the ships comply with the regulations, a few shipping companies seem repeatedly to use non-compliant fuel.
Other patterns we can see are that vessels that only rarely come into these waters break the rules more frequently. In addition, it’s more common that vessels emit excessive sulfur as they are leaving the SECA rather than on the way in, when they risk an on-board inspection. Some ships that have installed abatement technique for sulfur, so called scrubbers, have been observed with high levels on multiple occasions.—Johan Mellqvist
One use of remote sensing is to advise port authorities as to which ships they should select for on-board fuel inspections. Such inspections are a prerequisite for taking legal action against rule breakers. Recently the Norwegian Maritime Authority fined a ship NOK 600,000 (about US$77,400) for non-compliance. This was detected by the Great Belt measuring station and reported to the Norwegian Authorities.
In general, the vessels carry both low-sulfur fuel oil and the less expensive high-sulfur oil on board. If they switch fuel well in advance of their passing of the measuring stations, they won’t be caught out. That’s why aerial monitoring is superior. It shows how much the vessels actually emit when they are out at sea and don’t know that they will be monitored.—Johan Mellqvist
The aerial surveys show that 13% of vessels in the western part of the English Channel, near the SECA border, were in violation of the sulfur regulations in September 2016. For vessels around Denmark, the corresponding figure is 6-8%, depending on time period.
The fixed measuring stations on the approach to Gothenburg, on the Oresund Bridge and the Great Belt Bridge show that between 2% and 5% of the bypassing ships use non-compliant fuel. This can be compared to on-board inspections showing non-compliance rates of around 5% of the vessels at port. This may indicate that some ships change to compliant fuels too late (when entering the SECA) or change to non-compliant fuels too early (when leaving the SECA), while aiming at compliance at the fixed stations where they expect to be observed.
There is a strong financial incentive for shipping companies to continue using the prohibited high-sulfur fuel. For example, they can save around 100,000 euros by using the cheaper, high-sulfur fuel on a single round trip between the UK and Sankt Petersburg. The entirety of this journey lies within the SECA.—Johan Mellqvist
Sulfur emissions are above all a health issue, but in the Nordic region, where the bedrock has low lime content, they also contribute to acidification in lakes and waterways. Since 2015, the Baltic Sea, the Kattegat, the Skagerrak, the North Sea and the English Channel have made up a sulfur Emission Control Area in which shipping fuel may contain no more than 0.1% sulfur. The rest of the EU follows the regulations set out by the UN’s International Maritime Organisation, IMO, which will reduce the maximum permitted sulfur content in shipping fuel from the current 3.5% (35,000 ppm) to 0.5% (5,000 ppm) worldwide by 2020.
Reducing sulfur emissions is very costly for shipping companies, no matter how they choose to meet the requirements. There are several alternatives:
Powering ships with the significantly more expensive low-sulfur heavy fuel oil (HFO).
Installing scrubbers on board to reduce sulfur emissions to the necessary degree.
Switching fuels entirely, for example to liquefied natural gas (LNG) or methanol.