Determining the feasibility of alternative energy carriers for implementation on a cruise ship in Northern Europe

Abstract

The maritime industry faces increasing pressure to reduce greenhouse gas emissions in response to international climate targets and increasingly stringent environmental regulations. This challenge is particularly relevant for the cruise industry operating in Northern Europe, where emission control areas and national regulations demand a transition towards low- and zero-emission operations. Although various alternative energy carriers have been proposed, limited research has systematically evaluated their applicability to cruise ships operating under the unique operational and regulatory conditions of Northern Europe.
The objective of this research is to determine the technical, economic, and regulatory feasibility of alternative energy carriers for new-build cruise ships operating in Northern Europe. A comparative assessment framework was developed that combines ship particulars, representative operational profiles, and energy carrier characteristics to evaluate alternative propulsion concepts. The model iteratively determines the required vessel modifications to accommodate different energy carriers and subsequently evaluates the resulting capital expenditure, operational expenditure, emissions, and regulatory compliance. Four representative cruise ship sizes, seven operational profiles, and five alternative energy
carrier–converter configurations were evaluated. The developed methodology was verified and validated using the Validation Square proposed by Pedersen.
The results show that hydrogen represents the most robust alternative energy carrier, remaining technically feasible for all evaluated ship sizes and operational profiles while also satisfying current and anticipated emission regulations. Batteries provide a viable zero-emission solution for shorter operational profiles but remain constrained by their low energy density, requiring significant increases in vessel dimensions for longer routes. Methanol proves technically feasible but is currently limited by high projected operational costs and its inability to fully comply with the strictest emission regulations in Northern Europe. Sensitivity analyses demonstrate that the conclusions remain robust under variations in the principal model assumptions and operational profiles.
This research contributes an integrated methodology for evaluating alternative energy carrier pathways during the early design stages of cruise ships. Rather than producing a detailed vessel design, the developed framework supports decision-making by systematically comparing technical, economic, and regulatory feasibility. The methodology provides a foundation for future studies and can be adapted to evaluate emerging energy carriers, new operational scenarios, and future developments in maritime regulations.