Desalination by solar-powered reverse osmosis in a remote area of the Sultanate of Oman

The Ministry of Water Resources successfully conducted an experimental study on the use of solar power to desalinate brackish ground water at their Heelat ar Rakah camp, a remote location some 900 km south of Muscat, the capital of Oman. The system comprises components for pre-treatment of pumped well water to separate hydrogen sulphide, acid dosing to correct the pH, cartridge filtration, a solar powered reverse osmosis unit, and a reject-water evaporation pond. The solar powered system comprises a 23.2 m² solar photovoltaic generator with a peak capacity of 3250 W_p, a boost charge battery of 200 Ah at 48 VDC, a charge controller, a sine-wave inverter of 3000 VA with an output of 230 V, 50 Hz, and necessary controls and instrumentation. The design water output of 5 m³/day during 5 h (of each day) was achieved, with the output sometimes exceeding 7.5 m³/day. The average cost of production is estimated at US$6.52/m³ over the 20-year lifetime of the equipment. The study has demonstrated that solar-powered reverse osmosis systems are particularly appropriate to remote locations that have limited or no access to supply services such as fuel, power or potable water.