Model proposal for generation and storage decisions of a grid connected hybrid energy system

Due to the crowded population and developing technology, energy demand increased in the world. In order to satisfy the increasing demand, new economical and environmentally friendly energy resources are sought. Renewable resources are seen as an appropriate solution in this manner, as they provide economical and environmentally friendly energy. On the other hand, the renewable resources provide variable amounts of energy due to various reasons, especially climatic conditions, can cause some problems such as energy shortages and low energy quality. The concept of hybrid renewable energy systems, which was put forward to eliminate this disadvantage, refers to the combined use renewable resources with or without grid connection. In this thesis, energy system in a district with potential in terms of solar and wind energy is considered. A three-objective mixed integer programming model has been proposed to determine the energy production, storage and purchasing decisions at hourly detail level in the grid-connected solar-wind hybrid renewable energy system with energy storage option. Prior to the solution of the model, hesitant fuzzy linguistic multi-criteria analysis was applied for the selection of the appropriate energy storage technology within the energy system and it was found that the use of flywheels was appropriate. Since the computational complexity of obtaining the solution to the problem for the data of a whole year is high, the solution of the model was obtained by using the Reference Point method, one of the multi-objective optimization approaches, over a four-week data set which represents the demand and capacity characteristics of four seasons in a year. Then, the solutions obtained for eight scenarios in which changes in capacity, demand and cost values in the model are considered, are classified as good, reasonable or bad by multi-criteria decision making method of ELECTRE-TRI. The results of the solution show that almost half of the electrical energy demand can be satisfied by renewable energy resources. These results demonstrate that the proposed model can be a guide for reducing foreign dependence on energy for our country.