A method for solidifying a polar substance, in particular water, is presented which comprises the steps of: providing a coolable, hydrophobic, preferably super-hydrophobic, condensation surface within an interior of a container; partially filling the container with a polar substance, preferably in liquid form, and an immiscible additive, preferably in liquid form, so that the condensation surface remains at least partially unsubmerged; cooling the hydrophobic condensation surface to a temperature Tcond below a solidification temperature Tsolid of the polar substance; and removing solidified polar substance from the container.