Role of Port Tugs in Ship-Borne Emissions: An Analysis in Turkey's Izmit Bay

Abstract

Thanks to the awareness created by the concrete effects of global warming and climatic irregularities, concepts such as carbon emissions, polluting gases, internal combustion engines, energy efficiency are gaining more and more importance in our lives globally. In this context, the maritime sector, which provides the transfer of 90% of global trade, has become the center of attention with its ships boasting huge machinery and has also been a subject of exhaust emission studies. The fact that approximately 70% of ship emissions occur in coastal areas requires more scrutiny of ships operating in these areas. Providing docking and departing services for ports, having small hull sizes compared to other ships but featuring big machinery in terms of power output (kW), port tugboats are a serious source of emissions. As a first in this literature, the present study aimed to make a 3-month emission inventory of port tugs in Izmit Bay, where Turkey’s largest shipping activities take place, and to compare it with emission studies for other ships. In the study period, port tugs’ emissions of CO2, NOX, SOX, VOC, PM, CO were calculated to be 7,398.88 tonnes, 121.09 tonnes, 66.43 tonnes, 2.13 tonnes, 4.27 tonnes, and 5.77 tonnes, respectively. This suggests that port tugs have a significant place among ship types in terms of producing exhaust emissions.