The overall objective of the POSEIDON project is to prepare the implementation of local value chains based on emethanol as fuel for shipping in the ports of Valencia and Thessaloniki. This will be achieved by connecting local stakeholders and collecting requirements through local Communities of Practice (COP), investigating CO2 valorisation routes, developing and demonstrating innovative solutions including a power-to-e-methanol pilot plant and 2- and 4-stroke engines, evaluating the technical, economic, environmental and social impacts at case study level, drafting roadmaps describing post project activities and making tools and knowledge accessible in an open science manner to remove barriers to implementation and foster the replication and upscaling of e-methanol ecosystems in EU.