A distillation unit for producing potable water using solar radiation is disclosed. The distillation unit includes a heating chamber defining an interior chamber adapted to contain a non-potable liquid for distillation, and a dome-shaped condensing portion having an inner surface and an outer surface, with the condensing portion disposed over the heating chamber such that the heating chamber and the inner surface of the condensing portion are provided in fluid-transfer communication. The distillation unit also includes a pre-heat jacket having a first surface and a second surface and an interior defined therebetween adapted to receive non-potable liquid for distillation therein. The first surface is disposed adjacent the outer surface of the condensing portion, and the pre-heat jacket defines an access entry for introducing non-potable liquid for distillation into the interior of the heating chamber. The distillation unit also includes a trough adjacent for receiving a potable liquid therein.