Abstract This paper considers the problem of Power Plant Preventive Maintenance Scheduling (PPPMS). The goal is to evaluate which generators must stop production to be checked periodically for safety reasons. Preventive maintenance is crucial because a failure in a power plant may cause a general breakdown in an electric grid. This situation might result in a disruption of electric service to customers. The objective is to perform the problem of PPPMS from a reliability perspective, so the reliability of the system is maximized. The model presented considers the integration of wind power plants or wind farms into a traditional electric generating system comprising thermal, hydroelectric, and nuclear power units. The resulting model is categorized as an optimization problem. A case study based on a real power system is presented. Its main objective is to validate the efficiency of the proposed analysis.