Towards green marine propulsion: comparative lifecycle evaluation of LPG and battery-electric systems for small vessels

This study assesses three eco-friendly propulsion systems for small-to-medium fishing vessels: liquefied petroleum gas (LPG) generator engine motor propulsion system (LPG G/E MPS), LPG main engine direct propulsion system (LPG M/E DPS), and battery electric motor propulsion system (battery electric MPS). Using life cycle assessment (LCA), life cycle cost assessment (LCCA), and a fuzzy technique, the environmental, economic, and technical impacts of each system are evaluated within the context of the power production structure of South Korea. The results show that LPG M/E DPS are a viable alternative to traditional fuels, with lower greenhouse gas (GHG) emissions than battery systems due to the fossil fuel-heavy electricity grid in South Korea. Additionally, transitioning the hull material from glass fiber-reinforced plastic (GFRP) to aluminum reduces both emissions and costs over the long term. This study not only highlights the necessity for regional considerations in adopting green maritime technologies but also demonstrates the potential for significant environmental and economic benefits through informed propulsion system selection.