POSEIDON puts forth a new concept where renewable energy sources are used, stored and converted in different carriers to meet the demand from diverse energy consumers with fruitful synergies with water usage. Thereby the project encompasses several stages structured in 7 work packages. The research units collaborate, exchange information and expertise to investigate the multi-objective feasibility of an innovative multiproduct integrated process for the energy supply and independence from fossil fuels in islands and coastal areas. A holistic approach addresses the proposed solution's technical, economic, environmental, and safety issues, including the social acceptance evaluation.