Energy analysis and optimization of a hybrid system of reverse osmosis desalination system and solar power plant (case study: Kish Island)

Today, the use of renewable energy such as wind energy and solar energy is very important due to its environmental friendliness. Solar energy is an important source of energy that has received special attention in recent years due to the rising cost of fossil fuels. In Iran, researchers and industry managers have attached special importance to the use of renewable energy. The purpose of this article is to use solar energy to supply desalination energy in Kish Island. In this study, thermodynamic and economic analysis of a combined reverse osmosis (RO) desalination system with a solar panel on Kish Island has been performed. Kish Island does not have a permanent river which does not have water all year around; hence, access to clean/fresh water, driven by solar power, on Kish Island as a tourism hub, has an effective role in preserving the environment and increasing the attractiveness of the island. Therefore, the supply of fresh water from the sea using water pre-treatment and reverse osmosis system can meet the need for a large part of the island for fresh water. In this study, the capacity of the desalination plant is about 7,200 cubic meters per day in order to supply fresh water to the urban population of the island (about 40,000 people). In designing the desalination unit to supply its energy requirement, first the appropriate membrane is determined from the simulation results and the power consumption of the system including pre-treatment and reverse osmosis system is calculated at 9,620,000 kWh of energy per year. According to the results, the total dissolved solids (TDS) of system effluent and Recovery percentage were 141.3 mg/L and 60.3%, respectively. Also, due to space constraints and based on the simulation results, in order to provide power consumption for the optimum case, 15,228 solar panel units have been proposed.