Advancing load-dependent emission factors for ships: Integrating alternative fuels, biofuels, and control technologies

Shipping is a high-energy-consuming sector and a significant source of climate-related and harmful pollutant emissions. In response to growing environmental concerns, the maritime sector has been subject to stringent regulations aimed at reducing emissions, achieved through the adoption of alternative fuels and emission control technologies. Accurate and diverse emission factors (EFs) are critical for quantifying shipping’s contribution to current emission inventories and projecting future trends under various policy scenarios. This study presents advancements in the development of emission factors for ships, incorporating alternative fuels, biofuels and emission control technologies. The methodology integrates statistical analysis of emission data from an extensive literature review with newly acquired on-board emission measurements. To ensure high resolution and applicability across diverse operational conditions, the emission factors are formulated as functions of engine load and categorized by engine type and fuel used. The results provide insights into the emission performance of ships and intend to support the development of robust, up-to-date emission models and inventories, contributing to the broader goal of sustainable maritime transport.