A solar chimney is a passive solar ventilation system that allows cool air into a building while pushing hot air out. During the day, solar energy heats the air within the chimney, causing an updraft. The suction created at the base of the chimney then ventilates the building.
A solar chimney must be higher than the building's roof level and must be built on the side of the building that faces the sun. Glazing the outside of the chimney increases absorption of heat, as the larger the surface area that receives heat from the sun, the more effective the heat exchange will be. The heating of the air in the chimney enhances the convection process and increases airflow through the chimney.