A good ventilation system needs to be ensured so as to reduce the requirements
requirements of artificial ventilation. This can be achieved through various techniques and devices.
- Wind towers are used in hot and dry climates for cooling purposes.
- The tower has openings at the top which direct wind into the building.
- The tower can have openings in one or many directions depending on the direction of wind flow.
- A necessary requirement for using a wind tower is that the site should have consistent winds at good speed.
- Passive cooling by induced ventilation is used in hot and humid climates as
well as hot and dry climates.
- This method involves the heating of air in a certain area of the building to
create a difference in the temperature of air causing it to move.
- Hot air rises and escapes to the atmosphere drawing in cooler air and thereby causing cooling.
- The earth air pipe system consists of a pipe buried at a depth of about 4 to 5
metres below the ground.
- The earth air pipe system takes advantage of the fact that temperature at a depth of about 4 to 5 metres is equal to the annual average temperature.
- Air is blown through it by a blower at one end of the pipe while the other end is connected to the building to which it supplies conditioned air.
- Air flowing through the pipe gets cooled (in summer) or heated up (in winter) before entering the living space of a building.
Source of all above images: Handbook on Energy Conscious Buildings