Analysis of hydrogen storage methods for decarbonizing maritime transport: a multi-criteria decision analysis tool

Decarbonizing maritime transport requires hydrogen storage technologies that are efficient, safe, and compatible with fuel cell systems. This study evaluates three hydrogen storage technologies (compressed hydrogen (CH2), liquid hydrogen (LH2), and metal hydrides (MH)) based on five key criteria: safety, autonomy, environmental impact, cost, and implementation feasibility. Applying two multi-criteria decision-making (MCDM) methods, Analytic Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), the alternatives are systematically ranked to identify the most suitable option. Both methods consistently highlight compressed hydrogen as the most viable storage solution, offering a good balance of safety, infrastructure maturity, and economic performance. Liquid hydrogen, despite its superior autonomy, is limited by high energy and infrastructure costs. Metal hydrides, although safer and more compact in terms of volumetric density, are limited by low gravimetric efficiency at the system level due to the additional weight of the storage material and associated components.