Recently, there has been a growing interest in wind solar hybrid power plants as a means to overcome the inherent intermittency in both resources. One crucial decision faced by a hybrid plant designer is to determine an allocation of land area between wind and solar installations so as to satisfy the generation requirements in terms of the power output by the plant along with the availability. In this paper, a methodology is proposed for this optimal allocation problem under the constraints of climate and weather conditions, land area available for renewable energy harvesting, and PV/wind turbine characteristics. Based on historical wind speed and solar insolation data for a given location, probabilistic models using parametric and non parametric estimation techniques are developed to capture the variability and periodicity in these resources. A probabilistic model for the hybrid system is also derived using which the optimal allocation that satisfies the generation requirements is determined. The proposed method is validated by performing a detailed experimental analysis on historical data for an arbitrary location on the globe. © 2012 IEEE.