Air Quality: Promising Results from ESTACA’Lab’s Study of Pollutant Emissions from Shipping
In 2022, ESTACA’s Air Quality team was commissioned by the ADEME (French environment and energy agency), to quantify pollutant emissions from ships and explore technical solutions to reduce them. The goal is to help shipowners limit atmospheric emissions from the development of shipping traffic, in marine ecosystems and ports. The results obtained show that ships with liquefied natural gas (LNG) engines produce lower greenhouse gas emissions than previously thought.
A study conducted as part of a project funded by ADEME
Since September 2019, the team led by Benoît Sagot, a teacher-researcher in ESTACA’s Air Quality and Pollution Control division, has been applying a fine particle measurement methodology used in other areas of transport to ships. Various solutions for reducing pollutant emissions were evaluated on ships belonging to different companies. The EMINAVproject, funded by the ADEME, comprehensively assesses both gaseous and particulate pollutant emissions linked to maritime transport. The study was carried out on two types of engines: conventional marine diesel engines with no pollution control systems, and engines running on liquefied natural gas (LNG). On Brittany Ferries’ Salamanca, two test campaigns quantified emissions of unburnt methane in the exhaust; an area where these engines could be improved, as methane is a powerful greenhouse gas. By analyzing engine loads over a full year, the study showed that emissions of unburned methane (methane slip), emitted by LNG engines, are almost 50% lower than the default values set out in European regulations on ship emissions. This is linked to relatively low engine emission levels, and above all to the operational profile of the ship, which makes long crossings between France, Ireland and Spain, with relatively short port approach phases.
Results appluaded by Brittany Ferries
The study, recently published on the ADEME website, gave rise to an article in the Journal of Marine Science and Engineering. It is based on direct measurements carried out on the Brittany Ferries ship Salamanca. It concluded that the average annual methane slip rate was 1.57%, well below the regulatory default values (up to 3.5%). These results are welcomed by Brittany Ferries, which is committed to finding solutions to reduce pollution from its ships.
“We fully support the principle of environmental responsibility. The scientific data we have today show that actual emissions from our LNG ships are significantly lower than expected. This should logically be taken into account in our regulatory declarations. We see these results as a sound basis for providing European and international regulators with suitable methodological tools”, says Christophe Mathieu, Managing Director of Brittany Ferries.
The study was also picked up in the press, such as Le Marin who recently interviewed Benoit Sagot.
