Validation of the estimated ships' emissions through an experimental campaign in port

Abstract

This paper presents a correlation between the gaseous pollutant concentration measured in port and the estimated in-port ship emissions based on AIS data for the port of Naples. With the aim of better monitoring the quality ship's plumes funnels, the concentrations of Nitrogen dioxide (NO2) and Sulphur dioxide (SO2) have been continuously measured, during an experimental campaign (May–June 2021) at a height of 20 m from ground level.An innovative bottom-up ship emission modeling system with an emission inventory was created; five principal steps were realized: acquisition and cleaning, construction of ship's database, analysis of ship routes and phases in port, calculation of fuel consumption, and emission. The updated methodology bypasses the typical fixed value of specific fuel consumption, which is obtained based on the engine type and fuels and uses a correlation with the real engine load. Several updates were adopted for the emission estimation, abandoning the constant emission factor with the use of a more detailed methodology. The correlation was obtained by taking into account the prevailing winds and the overlap between the experimental campaign and the emission inventory on particular wind sectors. As a results correlations between the pollutant flow rates estimated from the AIS data and the concentrations measured during the experimental campaign, have been find (0.97 for SO2 and 0.80 for NOX).