Economic evaluation of desalination by small-scale autonomous solar-powered membrane distillation units

Solar-powered desalination is an attractive and viable method for the production of fresh water in remote arid areas. One of the most important factors determining desalination decisions is economics. This paper presents an economic assessment performed to estimate the expected water cost, which is the ultimate measure of the feasibility of the stand-alone system. Based on the calculations, the estimated cost of potable water produced by the compact unit is $15/m3, and $18/m3 for water produced by the large unit. Membrane lifetime and plant lifetime are key factors in determining the water production cost. The cost decreases with increasing the membrane and/or the plant lifetime.