NOVELTY - The method comprises passing a concentrated ionic solution through a first pathway in a reverse electrodialysis unit comprising a membrane stack having electrodes and alternating cation and anion exchange membranes, and passing a dilute ionic solution through a second pathway in the reverse electrodialysis unit so that solute from the concentrated solution in the first pathway passes through the membranes to the dilute solution in the second pathway for generating electricity. A concentration of solute in the dilute ionic solution as it enters the reverse electrodialysis unit is 0.05 mol/l.    USE - The method is useful for generating electricity (claimed).    ADVANTAGE - The method is capable of generating electricity without mixing of the raw streams exiting the reverse electrodialysis unit and fouling the solution by contaminants in an environmentally-friendly manner.    DETAILED DESCRIPTION - The method comprises passing a concentrated ionic solution through a first pathway in a reverse electrodialysis unit comprising a membrane stack having electrodes and alternating cation and anion exchange membranes, and passing a dilute ionic solution through a second pathway in the reverse electrodialysis unit so that solute from the concentrated solution in the first pathway passes through the membranes to the dilute solution in the second pathway for generating electricity. A concentration of solute in the dilute ionic solution as it enters the reverse electrodialysis unit is 0.05 mol/l. The ionic solutions comprise water and a salt. The salt has solubility, in water at 20 degrees C, of 8 mol/kg. The dilute and/or concentrated ionic solution comprises a water-miscible organic solvent. The method further comprises regenerating the concentrated and dilute ionic solutions from the solutions exiting from the reverse electrodialysis unit and recycling the regenerated concentrated and dilute solutions back through the respective first and second pathways in the reverse electrodialysis unit. The method is performed such that the S1/S2 is greater than Y, where S1 is the concentration of solute in mol/l in the concentrated ionic solution as it enters the reverse electrodialysis unit, S2 is the concentration of solute in mol/l in the dilute ionic solution as it enters the reverse electrodialysis unit and Y is 30. A flow rate of the ionic solutions through the pathways is less than 4 cm/s. A half of the membranes has a thickness of less than 250 pm, and comprises an ionically-charged polymeric layer obtained from a curable composition. The curable composition comprises 2.5-70 wt.% crosslinker comprising acrylamide groups, 20-65 wt.% of curable ionic compound comprising ethylenically unsaturated group and anionic group, 5-45 wt.% solvent and 0-10 wt.% of free radical initiator. An INDEPENDENT CLAIM is included for a device for generating electricity.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a method for generating electricity.    Dilute ionic solution enters unit (202)    Regeneration unit (203)    Inlet (204)    Outlet (208)    Pump. (230)