Date of Award
2025
Document Type
Thesis
Degree Name
Doctor of Philosophy in Maritime Affairs
Specialization
Ph.D (Maritime Affairs)
Campus
Malmö, Sweden
Abstract
This thesis extends the scope of IMO maritime decarbonization studies by incorporating cradle-to-grave approaches. This study advocates for an approach incorporating cradle-to-grave resource efficiency and carbon neutrality, assessing cumulative energy demand and net freshwater withdrawal as key sustainability metrics. The thesis specifically addresses the question of the sustainability of decarbonization strategies centred on substituting fossil fuels with synthetic alternatives and offsetting the remaining carbon footprint. Advanced ship energy modelling: The thesis first introduces a ship energy model capable of evaluating ships’ fuel consumption with various propulsion and energy generation options. The model simulates energy transfers across a concept ship’s systems, achieving an accuracy of 11% with 90% confidence when compared to real-world data. Lifecycle assessment of net-zero ship concepts: The energy modelling tool is further incorporated into a comprehensive life cycle assessment framework, evaluating carbon, water, and energy footprints from cradle to grave. At this point, the analysis of the carbon- water-energy impacts related to a 14k TEU capacity containership running on synthetic fuels and with net-zero GHG offsetting reveals: Potential reductions in GHG impacts of 66-97%, before applying carbon offsetting Increased energy demands of 95-150% for net-zero applications Variable water requirements, ranging from 0.9 to 121 times the initial ship footprint These results illustrate the inherent trade-offs in decarbonization strategies, where reducing the carbon footprint can significantly increase energy and water demand. Possibly, this phenomenon may stress energy or water security’s long-term sustainable objectives. Energy reduction strategies: Finally, the impact of energy efficiency measures on the energy intensity of net-zero ships is examined through a dedicated analysis. In a case study centred on container transport across the Atlantic ocean, wind-assisted propulsion, propulsion optimization and speed reduction achieved significant energy reductions ranging from 46.3% to 61.7%. Although substantial, these improvements do not resolve concerns about the sustainability of decarbonization strategies with synthetic fuels, especially when compared to current and future plans for renewable energy production. This underscores the need for energy resilience strategies specifically adapted to the maritime industry. The research concludes that incorporating comprehensive sustainability assessment methodologies into the IMO’s decarbonization framework is crucial to address future challenges, ensuring both environmental progress and long-term viability for the shipping industry.
Comments
978-91-988966-4-0