By Raghuram Vemula
Creating micro climates conducive for a healthy and congenial life is key to creating a vibrant eco habitat. The concept of Thermal Comfort is key to understand the micro climate and temperature within and around a locality. Hence, Thermal comfort is used as an important metric which helps in designing the eco-habitats. It informs the overall master plan and various components that form part of the final built environment in the Eco-habitat, including placement of dwelling units, avenue plantation, community farming spaces, forest areas etc.
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) is an Apex body in the Unites States of America which formulates guidelines on Thermal Comfort. The ASHRAE Standard 55 defines thermal comfort as “that condition of mind that expresses satisfaction with the thermal environment”. In India, the Indian Society of Heating, Refrigerating and Air Conditioning Engineers (ISHRAE) is the Apex body which formulates relevant guidelines which are in line with the ASHRAE guidelines.
Thermal comfort is influenced by six factors which can be grouped into two broad categories:
1.Personal Factors: Includes clothing, metabolic rate etc.
2.Environmental Factors: Includes indoor air temperature, mean radiant temperature, air speed, and relative humidity.
While the personal factors vary with each individual, the environmental factors can be used to design spaces with better Thermal Comfort. In the following paragraphs, the relationship between temperature and Thermal discomfort is presented with focus on an analysis undertaken by us for our upcoming community at Antharam.
The temperature in a built environment can be reduced through climate responsive building and environment design. In our upcoming community of Organo Antharam, we have undertaken Outdoor Thermal Comfort Analysis for “Rurban Hive”- one of the three main social gathering spaces in the community. The analysis was undertaken with simulations for temperature with trees and without trees in and around the Rurban Hive.
As shown in the picture below, the percentage of time comfortable all throughout the year has increased from 73.6% without trees to 93.90% with trees. Similarly, the percentage of heat stress decreased from 9.71% without trees to a remarkable 0% with trees.
Picture: Shows the difference in thermal comfort indicators with and without trees.
Thermal comfort is closely related to energy consumption in any built environment. A substantial amount of energy goes into reducing the Thermal Discomfort, especially with air conditioned buildings where close to 40-60% of the total energy used in such buildings (as per position paper issued by ISHRAE).
Follow our blog posts to know more about energy consumption reduction through design of buildings including the dwelling units to by improving the Thermal comfort