The aims of this paper are: to demonstrate the feasibility of the desalination of brackish water from aquifers (total dissolved solids = 2300-5100 g m(-3)) by means of an electrodialysis system powered directly by photovoltaic solar panels, and improve the mathematical model developed in a previous work in order to apply it to real brackish waters. The application of this model allows to predict the behaviour of the electrodialysis-photovoltaic system under different operational and meteorological conditions, and the time required to reach a given final concentration. Finally, the cost of electrodialysis-photovoltaic systems for small applications in isolated locations with lack of electric grid has been estimated. (C) 2008 Elsevier B.V. All rights reserved.