The enhanced vulnerability of insular regions to climate change has been recently recognized by the European Union, which highlights the importance of undertaking adaptation and mitigation strategies according to the specific singularities of the islands. In general, islands are highly dependent on energy imports which, in turn, feature a marked seasonal demand. Efforts to reduce greenhouse gas emissions in these regions can therefore fulfill a twofold objective: (i) to increase the renewable energy share for global decarbonization and (ii) to reduce the external energy dependence for isolated (or interconnected) systems in which this can only be achieved with an increase of the renewable energy share. However, the increase in renewable technologies makes energy generation more dependent on future climate and its variability. The main aim of this study is to analyze future projections of wind and photovoltaic potential, as well as energy productivity droughts, on the main Euro-Mediterranean islands. Due to the limitations in land surface available in the islands for the installation of renewable energy capacity, the analysis is extended to offshore wind and photovoltaic energy, which may have an important role in the future increases of renewable energy share. To that end, we use climate variables from a series of simulations derived from Euro-CORDEX (Coordinated Downscaling Experiment) simulations for the RCP2.6 and RCP8.5 emission scenarios. A special effort is performed to normalize projected changes and the associated uncertainties. The obtained normalized changes make it easier the intercomparison between the results obtained in the different islands and constitute condensed and valuable information that aims to facilitate climate-related policy decision making for decarbonization and Blue Growth in the islands.