Wind turbine power curve portrays the relationship between the wind speed and output power of the turbine. Wind speed values ranging between cut-in speed and cut-out speed acquire the most vital role for estimating wind power curve models. All wind turbines have different cut-in and cut-out speed limits and generation of electricity could be accomplished in a definite interval that could be termed as affective interval. This paper presents the development of parametric model of wind turbine power curves. An evolutionary strategy algorithm is used to build a nonlinear parametric model to monitor the performance of wind turbine. The parameters of these logistic expressions have been solved using firefly algorithm. The wind turbine power curve is constructed using historical wind turbine data obtained from three different wind turbine manufacturers. © Springer India 2015.