Membrane desalination helps in responding to increasing freshwater (FW) global demand. Energy requirements of desalination technologies compromise its environmental sustainability. The integration of renewable energies might improve the sustainability of desalinated water over other alternative FW sources. This chapter discusses the sustainability of electrodialysis (ED) powered by photovoltaic solar (PV) energy as one of the most promising configurations for brackish water. Environmental issues, with a special focus on energy consumption as a function of salinity, and economic issues have been considered. Energetic considerations have also been deeply discussed. Reverse osmosis has been taken as the reference technology. The main identified barriers for ED-PV preventing a larger market penetration are the matching of the intermittent output of renewable energies with water demand, the lifetime of membranes, the efficiency of solar panels, and the high production cost of FW compared to its low market price as a commodity.