Hybridization utility and size optimization of a stand-alone renewable energy micro-grid

Optimization of the stand-alone micro-grid is needed to minimize energy generation cost and environmental impacts. Protect the environment and saving cost can be obtained by choosing renewable energy sources as the power generation, such as photovoltaic (PV) and wind turbine. In this paper, authors investigate the hybridization utility and size optimization of a stand-alone micro-grid using the genetic algorithm. The considered micro-grid consists on PV generator, wind turbines and storage batteries. This study is based on a bi-objective optimization process. The life cycle cost (LCC) and the loss of power supply probability are respectively the economic criterion and the system reliability criterion under constraints. The energy modeling of the system's components enables energy flows simulation and further objective functions evaluation. The meteorological data of the location situated in Tunisia are considered. In order to study the resources randomness impact on systems optimal design, the data relating to December and August are used as references respectively to winter and summer. According to hybridization study, the hybrid PV/wind/battery system is the most appropriate system configuration for the studied location for both seasons compared to PV/battery or wind/battery. Results showed the significant influence of the battery bank design on the systems reliability and LCC.