Providing electricity in non-interconnected islands is a big challenge, exacerbated by the high cost of transporting fossil fuels and the non-viability of extending grid connections. Currently, diesel power plants provide almost all the electricity demand in these areas and installing renewable energy systems is deemed a practical solution to boost these communities’ energy transition and self-sufficiency. This thesis aims to determine the technical potential of wind and photovoltaic renewable energy sources on the fourteen non-interconnected Sicilian minor islands, through an original and scalable methodology to facilitate proper planning of the energy transition process of these territories. The methodology is based on a spatial energy planning approach, which considers normative constraints, mainly about environment and landscape safeguard, on a national, regional and local scale, beyond the techno-economic aspects, to determine the suitable areas for renewable energy exploitation.