A solar-powered airship with a hull configured to contain a gas and at least one propulsion assembly with a propulsion device and electric motors configured to drive the propulsion device. The airship may also include a power supply system including solar panels operatively coupled to the electric motors and configured to supply power to the electric motors. The power supply system may also include batteries operatively coupled to the solar panels and configured to receive and store electrical energy supplied by the solar panels, the batteries being further operatively coupled to the electric motors and configured to supply power to the electric motors. The batteries may each be located within an outer envelope of the airship defined by the hull of the airship in a position selected to provide ballast. The solar-powered airship may also include a cargo system configured to contain passengers or freight.