Theoretical analysis of a reverse osmosis desalination system driven by solar-powered organic Rankine cycle and wind energy

Abstract

The utilization of renewable energy for desalination can solve the problems of energy crisis and fresh water shortage. In this study, a reverse osmosis (RO) desalination system driven by solar-powered organic Rankine cycle (ORC) and wind energy is proposed, which is different from the current desalination system driven by single energy source. In order to ensure the continuous production, energy storage units are employed. A mathematical model is established to simulate the overall system which mainly consists of a solar collector subsystem, an ORC subsystem, a wind power subsystem and a RO desalination subsystem. The sensitive analysis of some key parameters, namely turbine inlet pressure, condenser temperature of ORC, feed water pressure and the water salinity, is conducted to determine the relationship between parameters and fresh water output. The result shows daily fresh water output increases with the increase in the turbine inlet pressure under the given conditions. The condenser temperature has a significant effect on daily fresh water output. With the increase in feed water pressure, the fresh water output and the required membrane area both decreases. The fresh water output is also sensitive to the water salinity, while the required membrane area is less sensitive to it.