Energy saving through passive cooling measures using bags with sawdust

Abstract

In recent times, due to limited availability of energy from conventional sources, its effects on the environment (depletion of the ozone layer and an increase in the average temperature of the earth) and their rising prices has drawn the attention of engineers and scientists, throughout the world. The need is being felt to conserve conventional sources of energy or to depend less and less on these sources of energy. One area, where considerable amount of energy is consumed is in creating comfort conditions in residential buildings. In the present work, a passive measure has been used to create comfort conditions in buildings using low cost material in summer. The comfort index used is ‘Tropical Summer Index’. In the test room of size (length = 7.8m, breath = 6m, and height = 3.8m), three fans are needed consuming about 225 watthour of electrical energy to keep the room in the comfort zone. This will eliminate the use of an air conditioner, which consumes a much larger amount of about 4 tons of refrigeration (15 kW). For residential buildings with smaller rooms, the number of fans required will be less. By adopting this measure, the use of an air conditioner can be avoided leading to a saving of electrical energy. It has been observed that during the summer season in India, present passive measures keep the room air conditioned well, within the comfort zone by using a meagre amount of electrical energy.

Keywords

• air-conditioner
• passive cooling
• energy saving
• air temperature
• comfort zone
• sawdust bags
• Tropical Summer Index