Introduction

Solar energy can be utilized in various ways – to provide electricity, mechanical power, heat and lighting. Passive solar heating and cooling can save substantial electricity bills. Design of a building is very important for tapping passive solar energy. The building and windows are designed in such a way that they carefully balance their energy requirements without additional mechanical equipment. Solar benefits are utilized through windows and pumps, and fans are used minimally.

Passive cooling covers all natural processes and techniques of heat dissipation and modulation without the use of energy. Some authors consider that minor and simple mechanical systems (e.g. pumps and economizers) can be integrated in passive cooling techniques, as long they are used to enhance the effectiveness of the natural cooling process. Such applications are also called ‘hybrid cooling systems’. The techniques for passive cooling can be grouped in two main categories: