Reducing pollutant emissions from vessel maneuvering in port areas

We propose an activity-based model to calculate ships' exhaust emissions while maneuvering in port. The exhaust emissions from the seven international commercial ports in Taiwan (namely Kaohsiung, Keelung, Taichung, Taipei, Hualien, Anping, and Suao) were calculated using actual data. Then, the regional ship exhaust emissions were estimated based on the number and size of ships and the type of fuel they used. Our method of predicting and evaluating the effectiveness of green port policies is shown to be intuitive and precise. Small vessels, which are the most common vessel type to enter and leave Taiwan ports, were shown to generate most of the emissions, but unit emissions from large vessels were the highest among three types of vessels (i.e., small, medium, and large). Moreover, greenhouse gas (GHG) emissions corresponded to sailing speed. Taiwan International Ports Co., Ltd (TIPC) has slightly reduced carbon dioxide equivalent and sulfur oxide emissions by implementing a green port policy, consisting of multiple ways of building a sustainable port environment (such as vessel speed reduction and use of low-sulfur oil). However, nitrogen oxide emissions have not decreased significantly. Our findings indicate that lower speeds and onshore power supply can reduce local air pollution, and assist transportation authorities, who should consistently monitor GHG emissions in port, to proactively respond to the International Maritime Organization's regulations for ensuring a sustainable future.

Automated summary

This study proposes an activity-based model to calculate ships' exhaust emissions during maneuvering in port. Actual data from seven international commercial ports in Taiwan were used to calculate the emissions, and the regional ship exhaust emissions were estimated based on ship number, size, and fuel type. The study finds that small vessels generate the majority of emissions, while large vessels have the highest unit emissions among different vessel types. The implementation of a green port policy has led to a slight reduction in carbon dioxide equivalent and sulfur oxide emissions, but nitrogen oxide emissions have not significantly decreased. Lower speeds and onshore power supply can help reduce local air pollution.