Supplementing our energy base with clean and renewable sources of energy has become imperative due to the present day's energy crisis and growing environmental consciousness. Wind is one of the potential renewable energy sources, which can be harnessed in a commercial scale for various end-uses. A precise knowledge of wind regime characteristics is a pre-requisite for the efficient planning and implementation of any wind energy project. In the present study, a method for characterizing wind regimes, bringing out their energy potential, is discussed. A Rayleigh distribution was adopted for defining the distribution of wind velocity in terms of its probability density and cumulative distribution functions, Expressions to compute the energy density, energy available in the wind spectra in a time period and the energy received by turbine have been developed. A method to identify the most frequent wind speed and velocity that carries maximum amount of energy with it. is also discussed. The analysis of wind energy potential of a eight sites in Kerala, India, adopting this procedure is presented. The performance of three wind turbines differing in their working velocity band, at these sites are compared. The effect of cut-in and cut-out wind speeds on wind turbine performance are also analyzed.