Analysis for Decarbonization Pathways for Shipping

Faculty of engineering, The Hong Kong Polytechnic University, HKSAR, China

^* Corresponding author: ruikan.chen@connect.polyu.hk

Abstract

As regulations and goals for reducing carbon emissions in shipping become increasingly clear, decarbonization will become the top priority for the development of shipping industry in the coming decades. Currently, the main source of CO₂ emissions from marine engines comes from the combustion of fossil fuels, while the operation of merchant ships typically requires striking a balance between equipment investment costs and the efficiency of CO₂ emissions reduction. Thus, choosing a more suitable approach for ships is a hot topic of concern. This article summarizes three decarbonization methods, including reduction of energy consumption by speed reduction and air lubrication, using low-carbon and carbon-free fuels to substitute conventional marine fuels, and carbon capture. These methods are analysed for their technical feasibility, decarbonization capacity, safety, economy, and technical readiness. To achieve the short-term CO₂ emissions reduction goal, there are various technologies to be applied, individually or in combination. Carbon-free fuels internal combustion engines can meet the long-term goal and its fuel cells will be the ultimate choice for net-zero scenario.