In the recent years EU islands, with more than 2.700 EU inhabited islands, have shown a clear trend towards decarbonisation, increasing the energy generated from renewable sources, while decreasing CO2 and NOx emissions. Currently, they are candidates to become the showcases of the energy transition in Europe and several success cases already exists, including the so-called 100% renewable islands, which expect to become fossil fuel free by 2030. On the other hand, despite sharing some common aspects with mainland systems, European islands face considerable challenges in meeting their energy needs in a sustainable, affordable and reliable way. The main challenge for the energy system is usually attributed to its geographical isolation, which is also a factor that has preserved their biological and/or geological uniqueness. This uniqueness requires energy systems and services to be tailored to their explicit needs. Considering this characteristic, we propose an island oriented holistic performance evaluation framework and an ICT infrastructure that will facilitate a unified European islands characterization and performance monitoring in this energy transition era.