Performance of a photovoltaic powered reverse osmosis system under local climatic conditions

Abstract

In addition to shortage of fresh water resources, Jordan is suffering from shortages in recoverable commercial energy sources such as crude oil and natural gas. The limited energy sources in Jordan makes considering renewable energy options such as solar power very attractive, especially for remote areas. This will be extremely important for small-scale applications. Due to prevailing tough conditions, such as low water quality and shortage in supplies, there is a large demand for small desalination units, not only in locations not connected to a water supply network, but also as units for additional or independent supply. In this paper, an experimental study was conducted to investigate the potential of the development of water desalination using photovoltaic powered system in Jordan. A testing rig was built, where a reverse osmosis (RO) desalination system driven by photovoltaic power is used. The RO unit consists of a five-micron sediment filter that is made of polypropylene, two active carbon filters with 1–2 micrometer hole diameter, and one polyamide TFC membrane. The system is mechanically powered, directly coupling the photovoltaic power system to a DC motor, which is coupled to a pump that is capable of providing sufficient torque to run the RO system. Two PV arrays are connected in series and tilted a 32° to the south. To study the effect of tracking on the performance of the system, a one-axis east–west tracking flat plate photovoltaic is constructed. Results for both, the fixed flat plate and the one-axis tracking system were compared. Output electrical current, voltage and power of pump’s motor were measured. Pure water flow rate, TDS and PH of produced water were measured for both systems. Analysis of results show that a gain of 25 and 15% of electrical power and pure water flow, respectively, could be achieved using the east–west one-axis tracking system compared with fixed flat plate.