Wind power reduces our exposure to fuel price volatility and abrupt supply disruptions; it has no CO2 emissions and increases energy security through the diversification of the energy portfolio. If well sited and dimensioned, wind farms may contribute to decreased electricity generation costs. This article presents a combined GISs (Geographical Information Systems) and CBA (Cost Benefit Analysis) approach, in determining the most feasible sites that would be suitable for the generation of wind energy in Terceira Island, which is aimed towards efficient policy designs. Data corrected with Wind Atlas Analysis and Application Program, from local effects of the territory, are used to determine potential energy. Furthermore, a CBA is performed, without taking into consideration subsidies and economic indicators are displayed in maps using GIS. Results indicated that Terceira Island has large available areas capable of generating wind energy at low prices. On Terceira Island, while considering a 1500 kW wind farm under the best siting conditions, it is estimated to achieve a Net Present Value of nearly 3 330 000.00 €, an Internal Rate of Return of nearly 26%, and a Levelized Cost of Energy of nearly 0.04 €/KW h, without incentives. The sensitivity analysis results indicated that reductions in the energy sold may drastically impair the feasibility of a wind energy generation project, and that increases in the lifetime of a project from 15 to 25 years may improve its feasibility. The minimum wind speed required to grant feasibility of investments on Terceira Island, for 1500 kW installed power, is 6 m/s, ceteris paribus. This analysis pointed out that Serra do Cume and Serra da Ribeirinha are the most suited for wind energy projects on Terceira Island.