Economic analysis of a stand-alone reverse osmosis desalination unit powered by photovoltaic for possible application in the northwest coast of Egypt

Abstract

The availability of fresh water and energy is the key factor for the development of many countries particularly those of over-populated arid areas. Potable water supply shortage and recent technological development have led to wider application of conventional, and yet advanced saline/brackish water desalination plants. Today, desalination methods require large amounts of energy, which is costly both in environmental pollution and in money terms. This study defines the main economic parameters used in estimation of desalination costs and limitation of the stand-alone, small size SWRO plants powered by photovoltaic (PV) at the northwest coast of Egypt. Moreover, a techno-economic study is made to estimate the actual cost of m3/fresh water production on real field measurements. All cost estimates are based on the prevailing prices during 2012–2013. The average unit cost of desalted water with the desalination unit powered by PV battery is 9.3–5.6 LE/m3, which is very high, but when using the unit with battery, the cost is reduced to 2.3–1.7 LE/m3 by increasing working hours to 24 h. Economical strategies should be developed for more reduction in cost, taking into account all phases from site selection and design to operation and maintenance and most importantly increasing the local manufacturing.