A Survey on Hybrid Renewable Energy Systems for Microgrid Application

High penetration of renewable energy could lead to minimizing the greenhouse gas emissions and petroleum dependency of a country. To achieve this, an optimized renewable energy integration model is required. Hybrid Renewable Energy System (HRES) is an integrated model of renewable energy generation and the load. Therefore, this model will depend on the renewable energy resource availability of a concerned geographical area and its local demand. There are many models to integrate renewable energy into an electrical grid. Among them islanded models without a grid connection are developed in rural areas due to their self-contained nature. These hybrid renewable energy systems usually have solar and wind energy as their primary energy source where a diesel generator is used as the backup supply. To integrate renewable energy, the integration model should be precisely designed. This paper discusses the renewable energy integration models in-depth from the view of distributed generation and micro grids. Different hybrid renewable energy systems were compared and assessed to evaluate their inadequacies and limitations. Future challenges and remaining issues are also discussed.