Abstract
This study examines the initiatives and innovations within the shipping industry aimed at addressing the critical challenge of reducing greenhouse gas (GHG) emissions while enhancing fuel efficiency in compliance with global regulations. In 2018, the International Maritime Organization (IMO) introduced an initial strategy to reduce GHG emissions from shipping by 40% by 2030 and 70% by 2050, relative to 2008 levels. Research on PT Pertamina International Shipping (PIS) indicates the establishment of a green shipping roadmap in 2021, which was subsequently updated in 2024. As part of its decarbonization initiatives, PIS developed the Vessel Emission Reduction Strategy 2025–2050 to support the IMO’s Net Zero Emissions (NZE) target by 2050. This strategy forms an integral component of PIS’s broader sustainability agenda, aligning with the IMO’s Energy Efficiency Existing Ship Index (EEXI) regulations and incorporating the systematic retrofitting of Energy Saving Device (ESD) during scheduled dry docking.
PIS has introduced combined ESD on its Very Large Gas Carrier (VLGC) fleet, integrating duct modifications (e.g., Mewis ducts, pre-swirl ducts) with rudder bulbs. This study presents a comparative analysis of combined ESD on two VLGC vessels, evaluating their performance against single ESD installations and baseline operations without ESD. The results indicate that combined ESD deliver significantly superior performance compared to single-device applications or pre-installation conditions. Key improvements include higher vessel speed, reduced hydrodynamic resistance, increased distance-to-fuel ratios, enhanced fuel efficiency, and improved Carbon Intensity Indicator (CII) ratings.
The adoption of combined ESD represents an innovative solution for PIS to reduce both operational costs and carbon emissions. Their implementation generated substantial benefits, including an 11.9% reduction in fuel consumption, cost savings exceeding USD 840,000 (based on 2025 fuel prices), and a 29% decrease in carbon emissions—all achieved without a single incident. Additionally, the CII rating was improved by 23%. Beyond improving business efficiency, the combined ESD initiative supports global decarbonization targets and provides a replicable model for adoption by other shipping companies worldwide. This study contributes to an enhanced understanding of the actual effect of applying combined ESD, which optimizes the hydrodynamic flow of the water body around the ship, leading to improved fuel consumption and CII rating.
Keywords: Energy Efficiency, Very Large Gas Carrier (VLGC), Energy Saving Device (ESD), Decarbonization, Net Zero Emission.