The electrification of the non-interconnected Greek islands is mainly based on Autonomous Power Stations (APS), which consume conventional fossil fuels at high energy production cost, while in most cases the contribution of Renewable Energy Sources (RES) (mainly wind) accounts for a small percentage of total electricity generation in these regions. On the basis of comparative analysis of alternative "development scenarios" for electricity generation, the main objective of the present study is to investigate the techno-economic viability of high Wind Energy (WE) share at local (island) level, in accordance to the energy and climate change commitments undertaken by the country, having as central feature large-scale penetration of RES. In this context, the possibilities of increasing WE contribution are examined through the use of an integrated theoretical model developed from first principles, assuming two main possible scenarios for covering future electrification needs of a medium-sized Greek island, i.e. Lesbos. The first scenario (S1) is based on autonomous development of the island keep using as main source for electricity generation oil products. The second scenario (S2) involves the interconnection (IC) of the island with the mainland grid for satisfying part of electricity demand by establishing two alternative solutions, i.e. S2a: without the contribution of local Thermal Power Plant (TPP) and S2b: TPP are maintained to ensure electrification of the island. Subsequently, the economic feasibility of the above options is investigated in terms of their Levelized Cost of Energy (LCOE), calculated for the time-period 20202045, including also a sensitivity analysis on worst/reference/best Cases for future electricity demand and production cost. According to the obtained results, IC of Lesbos island with the mainland grid presents considerable economic interest in comparison to autonomous development, with WE having a dominant and an essential role towards that direction. (C) 2016 Elsevier Ltd. All rights reserved.