Pre-Feasibility Study and Unit Sizing of Hybrid Renewable Energy System for a Global System for Mobile Communications (GSM) Station in Tabriz, Iran

Wind and solar energy are widely used in power generation systems due to the fact that they are free and produce no pollution tcomparing to fossil fuels. From an economic point of view, renewable energy resources increase the power generation versus the cost of the system, and their usage is in high pace griwth. The renewable energy resources are used in a hybrid system along with non-renewable energy resources. A hybrid system consists of two or more energy resources, power electronic equipment, controller and one or more optimal energy saving system. This paper, as part of broader research, presents pre-feasibility and unit sizing analysis of a hybrid system equipped with renewable energy resources for the city of Tabriz-Iran (46°26^∕ E, 38°06^∕ N). A GSM telecommunication station is used stand-alone load system as the case study. Renewable energy resources include photovoltaic (PV), and a wind turbine as main resources and fuel cell and a battery stack as the backup and energy storage systems. An electrolyzer is used to provide hydrogen for the fuel cell system. Feasibility analysis and unit sizing of this system are performed based on meteorological data of solar insolation and wind speed, and an optimal model is extracted through the results. It is expected that the presented system provides great opportunities in the future. Simulation of the feasibility analysis is performed by utilizing HOMER software. The results propose a low-cost optimal performance hybrid system. Hybrid Optimization Model Electric Renewables (HOMER) software (developed by National Renewable Energy Lab-NREL) is used as a tool for sizing and optimizing of the system. Sensitivity analysis is performed based on wind energy data and fuel-cell cost. The load is a stand-alone GSM telephony station which consumes 60kW per day and maximum 3.8kW per hour. It is found from this analysis that wind/PV/electrolyzer/ battery/fuel-cell is not the best solution at present. Shortly, according to improve prediction in fuel-cell technology, it is expected that using this source as a backup will be the best option due to the decrease in fuel-cell cost up to 65 percent. Size, application and economic criteria are studied.The pre-feasibility analysis had been performed in this paper for a hybrid system with renewable energy resources as power supplier combined with non-renewable energy sources. The stand-alone load is a GSM telecommunication station in the city of Tabriz. Wind and PV are used as main resources and fuel cell and battery as energy storage and backup. HOMER software is used for optimizing the feasibility and unit sizing and combination of the system. Optimal results presented for this system. It can be used in regions with weather conditions similar to Tabriz. The results provide great opportunities  of this hybrid system.