The utilisation of hydrogen is being explored as a viable solution for reducing carbon emissions in port operations, with potential applications in cargo handling, transportation, and shipping vessel operations. To comprehensively list the decarbonisation options in ports, this study conducted a Systematic Literature Review to identify and then survey twelve highly cited review papers. Initially, a typology approach was used to categorise the decarbonisation options by activities and technologies. Subsequently, the study introduced a novel Port Energy Map to reveal the energy system pathways and their interconnections. Each pathway was then converted into a simpler linear sequence of activities, shown as a Port Energy System Taxonomy, which outlines the energy supply and energy-using activities. By utilising this taxonomy and map, the study identified opportunities and research gaps for integrating hydrogen technologies into port energy systems, which serves as a valuable tool for assessing port decarbonisation options.