Taking into account the world’s energy crisis and not having Uruguay neither oil nor natural gas fields, the government is encouraging the development of renewable energy projects for generating electricity. The goal is to diversify the energy dependence by reducing the weight of oil in the country's energy matrix. In this context, a number of bids are being made for the purchase of energy from new power plants to generate electricity using biomass, waste from industrial parks, wind and small rivers. The plan is to incorporate approximately 400MW from wind power to the system in the next six years. The peak demand is now around 1400MW. One characteristic of wind energy is its high variability of power due to changes in then wind speed. The Uruguayan system has a high component of hydroelectric generation, having a lake with a capacity of 90 days and three others with capacity of around 7 days. In this scenario, it is necessary to consider the wind power in the system’s dispatch, and then evaluate the way in which such inclusion can bring changes in the policy of optimal use of the country’s resources. This paper presents the model developed for this purpose. The model takes into account the temporal autocorrelation of wind speeds and its annual and daily seasonality. The annual seasonality in Uruguay is important because there are few months in the year in which there is plenty of water and others where there are shortages, so the possible correlation between wind and water availability must be represented. The daily seasonality is also important for its tuning with the consumption curve of the system. Comparative results of the use of water from the reservoirs are presented for a scenario in which the expansion of the system is based on wind energy versus a scenario in which the expansion of the system is based on fuel oil fired generators.