A system and method for providing a rotational output using a non-combustion heat source. The system may include a sealed chamber and a triggering element. The sealed chamber may contain a substance that expands when heated and contracts when cooled. The sealed chamber may include a displacer capable of moving within the sealed chamber, wherein the displacer moves when the substance is heated and a heat source situated within the sealed chamber. The heat source heats the substance when activated. The triggering element is coupled to the sealed chamber and activates the heat source. The system may include mechanisms for translating the displacer movement into a rotational output or other output.