USING SOLAR ENERGY TO DRIVE A REVERSE OSMOSIS PLANT FOR SEAWATER DESALINATION IN SUDAN

Abstract

In the last few decades, water shortage problems have emerged, especially in developing countries. Under the current circumstances, it is estimated that by 2050 about 40% of the world population will suffer water shortage. Desalination of seawater and brackish water can play a special role in solving this problem. Among desalination techniques reverse osmosis (RO) is predominant due to its advantages. Regardless of the type of technology used, the water desalination process requires a large amount of energy. In lots of places around the world, fresh water shortages are accompanied by an abundance of solar energy. Many small towns and villages scattered along the Red Sea coast in Sudan suffer from a severe shortage of fresh water and electricity supply, especially during summer months. In this study, one of the existing desalination plants in the city of Portsudan (eastern Sudan) was putted under consideration to investigate the possibility of shifting it to run on solar energy instead of electricity from the city grid. The plant is a reverse osmosis unit with capacity of 7 m3/h. It consumes energy in rate of 6.6 kWh/m3. PVsyst software have been used extensively to design and simulate the solar photovoltaic system which can drive the desalination unit. Results showed that with PV array total power of 107 kWp and 20160 Ah battery capacity, the system can work steadily for 8 hours daily to produce 56 m3/day of fresh water. The obtained annual performance ratio (PR) of the solar system is 61.2% with solar fraction equal to 100%.