Challenges of integrating hydrogen energy storage systems into nearly zero-energy portsChallenges of integrating hydrogen energy storage systems into nearly zero-energy ports Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2024-05-102022enSustainable development is the primary global goal for port authorities to maintain and improve their commercial activity and attractiveness. The need to diminish their environmental impact ought to be accomplished by reckoning economic and social euphoria sectors. This research aims to convert a traditional port to a sustainable one while eliminating its carbon footprint emissions. The incorporation of cold ironing technology is investigated to reduce the emissions caused by the operation of berthing vessels' auxiliary engines and to set the ground for future legislation. After studying and evaluating the current strategies, and technologies, thirteen scenarios were conceptualised, simulated, and evaluated using the HOMER PRO software. For each scenario, the port's autonomy is ensured by generating renewable energy and storing excess energy in a hydrogen storage system. The optimal solutions were chosen, utilising the actual area's data. In particular, zero carbon footprint emissions for the port's operation were achieved, and the Levelised Cost of Energy was reduced by 51.8% and 41.2%, respectively, by incorporating or not the cold-ironing technique. Also, the port is capable of operating autonomously for a whole day. Finally, this study proves that small-sized ports can implement cold-ironing technology and enhance their energy efficiency via a renewable hydrogen system.The research work and this scientific paper were supported by the Pancretian Endowment Fund and the Onassis Foundation - Scholarship ID: G ZO 026–1/2018-2019.http://creativecommons.org/licenses/by/4.0/Energy241 Vichos Emmanouil Βηχος Εμμανουηλ Sifakis Nikolaos Σηφακης Νικολαος Tsoutsos Theocharis Τσουτσος Θεοχαρης Elsevier Cold ironing Hydrogen energy storage system Nearly zero energy ports Hybrid renewable energy system