Costs and feasibility of repowering wind farms.

The aim of this paper is to determine the main costs and the feasibility of repowering wind farms. For this purpose, two study methods, which depend on legal and wind turbines issues, have been considered. They will provide nine alternatives, whose study will be developed. The methodology has been applied to the particular case of Galicia (North-West of Spain), where there is a good onshore wind resource. Calculations indicate the costs, the Net Present Value (NPV), the Internal Rate of Return (IRR), and the Pay-Back Period of these alternatives. In addition, a sensitivity study has analyzed the main variables of dependence in repowering wind farms. Results show that repowering can be a new alternative for onshore wind farms in areas where old wind turbines are currently installed. [ABSTRACT FROM AUTHOR]