RESUMEN
Shipping industry, like other industrial sectors, suffers from an energy efficiency gap. The majority of the literature focuses more on identifying barriers than proposing solutions. This study seeks to achieve two objectives: first, to provide a repository of barriers/solutions for shipping decarbonization, and second, to identify an optimal policy framework to combine all the solutions in the best way. In this vein, a two-phase literature review is conducted; at the first phase, with a focus on energy efficiency in non-maritime literature, a barrier template is developed which is applied to maritime literature in the second phase. The result is a comprehensive repository of barriers and solutions for shipping decarbonization. Our findings indicate that, while policy deficiencies are the most prevalent barriers, the financial footprint is clearly evident in most solutions. Therefore our recommendation is an economic-based policy with an integrated approach that supports all the possible solutions in parallel.