EXISTING TECHNOLOGIES AND SCIENTIFIC ADVANCEMENTS TO DECARBONIZE SHIPPING BY RETROFITTING

Aleksander A. Kondratenko ^a,b , Mingyang Zhang ^c, Sasan Tavakoli ^d , Elias Altarriba ^e,f, Spyros Hirdaris ^g

^a Department of Space, Earth and Environment, Chalmers University of Technology, Gothenburg, Sweden
^b Faculty of Industrial Technology, Technical University of Sofia, Sofia, Bulgaria
^c Department of Mechanical Engineering, Marine Technology Group, Aalto University, Espoo, Finland
^d Department of Infrastructure Engineering, University of Melbourne, Australia
^e South-Eastern Finland University of Applied Sciences (Xamk), Logistics and Seafaring, Kotka, Finland
^f Kotka Maritime Research Centre, Kotka, Finland
^g American Bureau of Shipping, Global Ship Systems Centre, Athens, Greece

ABSTRACT

The maritime industry is transporting about 90 % of world commerce, contributing to the global greenhouse gas emissions that cause climate change. Increasing pressure on the sector to reduce its carbon footprint requires developing specialized energy-efficient technologies and studying their compatibility with modern safety and sustainability expectations of the waterborne sector. This research supports the United Nations sustainable development goals SDG 7 (Affordable and clean energy) and 13 (Climate Action), and reviews available tech nologies for shipping decarbonization through design for retrofitting. Promising research areas to improve the energy efficiency of ships could focus on design concepts and methodologies, fluid dynamics, and artificial in telligence. The study suggests that while individual promising decarbonization technologies are available, a comprehensive and coordinated approach is necessary to decarbonize global shipping efficiently. The study identified three promising paths of ship retrofitting to meet the International Maritime Organization decar bonizing objective 2050, aiming at a 70 % reduction of annual greenhouse gas emissions compared to 2008. The first path – using green energy sources (e.g., ammonia, battery, and methanol) – requires scaling up technologies and developing a regulatory framework and control of the lifecycle of the fuel production process. The second path – using ship-based carbon capture technologies, ship design (e.g., hull retrofitting, air lubrication, and wind-assisted propulsion), and operation solutions (e.g., weather routing and logistics planning) – requires building more CO2 storage and control of the lifecycle of liquified CO2. The third path – using biodiesel as a fuel in combination with ship design and operation solutions – requires extending feedstock for biodiesel production.