Reliability and reserve capacity assessment of isolated power systems with increased penetration of renewable energy sources

The increased penetration of renewable energy sources in the modern electric power systems is favoured by many incentives being applied under the framework of the competitive electric energy market. The generating units using renewable energy sources may contribute significantly to the supply of the system load demand requirements while keeping the respective operating cost and environmental impact quite low. However, the increased use of these generating units may affect significantly the reliability and overall operational performance of the power systems since their availability level and effective use are restricted by the random and unpredicted weather conditions. Additional security problems are identified in isolated power systems since these systems do not have any interconnection links with neighbouring networks. The purpose of this paper is to describe the main features of a developed computational methodology that can be used for the reliability and reserve capacity assessment of isolated power systems incorporating a high penetration of wind parks. This methodology applies the Monte Carlo sequential simulation approach for simulating realistically all the system operational features and procedures. An application is included for assessing the overall operational performance of a typical system based on the isolated power system of Cyprus. Alternative planning and operational schemes of the system are examined concerning various technical and operational features, including the wind penetration level and the spinning reserve requirements. The obtained results are compared in order to determine the impact of the system features on its operational performance.