Economic feasibility of alternative designs of a PV-RO desalination unit for remote areas in the United Arab Emirates

Abstract Reverse osmosis (RO) is an electrically driven technology characterized by significantly low specific power requirements. In the meantime, coastal arid areas, as in the United Arab Emirates (UAE), are blessed with exceptionally high solar radiation most of the year. Normally, those areas have no access to municipal water network and the local power grid. In addition, primary fuel cost is soaring up while the need to maintain clean environment is becoming an increasingly important issue worldwide. In view of these facts, it is seen that a small seawater RO desalination unit powered by a photovoltaic array presents an ideal solution to provide small communities isolated at remote areas with freshwater. This paper explores economic feasibility of three alternative configurations of an autonomous SWRO unit for remote areas in the UAE. Three different scenarios are proposed here for the powering system where the unit is driven either by a diesel generator, a PV-diesel hybrid system or solely driven by solar panels without battery backup. Simple models are utilized to design the RO plant and produce a preliminary design of the PV array. Detailed cost calculations are performed for each one of the suggested configurations to assess their feasibility and cost effectiveness. These calculations are done in view of the environmental impact of each design and within the possible ranges of solar panels and primary fuel costs.