Buildings contribute to one third of global energy enduse, and this number is expected to rise with increasing urbanization and ever expanding cities. There is an urgent need to ensure that the future development is done in the right way so that we conserve natural resources for our future generations. 'Green Buildings' are rightly designed buildings that consume less energy, less natural resources like water, use sustainable materials, cause minimal damage to surroundings and most important of all, provide a healthy space for the occupants. 

There is a lot to green buildings than the complex jargon and the lack of information about their actual performance. Green buildings can be achieved by designing the right way from the early stages of design. All stakeholders of the building- owner, end user, architect, all consultants (lightning, HVAC, plumbing, etc.) need to work together from initial design stages so that they can understand the impact of one parameter of the building on the other and design accordingly.

An efficient building facade with optimum window-wall ratio, insulation on walls and roof, and use of high performance glass and shading for windows will have a significant impact on the air conditioning and lighting requirement inside the building. Lighting system needs to be designed as the interior layout to achieve a specific lighting level for the space. Lighting system also needs to be programmed based on the natural light availability in the space.

Air conditioning systems need to provide thermal comfort to occupants and get adequate fresh air into the space to ensure good air quality. Rainwater harvesting should be integrated with the building or facade design to ensure rooftop rainwater is collected and used effectively. Green buildings are done in the right way with focused efforts have minimum negative impact on environment. It is not just enough to design a building that is very efficient but more important is to ensure efficient performance for the life of the building. Green buildings at Infosys have an annual Energy Performance Index (EPI) of 75 kWh/sqm as compared to a regular building having EPI of 200 kWh/sqm. A focused team of experts monitor performance of each building of Infosys online and ensure high efficiency is maintained and corrective measures are immediately taken up whenever there is a deviation in performance. 

Every unit of electricity saved is equivalent to two units generated. So, lower energy consumption means enabling electricity access to more households. Similarly, for water, which is already a scarce resource, conservation is very important considering the fact that a large population globally do not have access to clean water. Green buildings also make great economic sense not only in the operational phase but in terms of capital cost as well. It does not require special expertise to understand that a glass building require large capacity of air conditioning compared to a building with 30 per cent glass. So, at the initial design stage, when the impact of different types of designs are studied, it can be easily inferred that sustainable designs can reduce the capacity of air-conditioning, thus reducing the capital cost of air-conditioning and associated electrical and other systems.

Another parameter more important than building performance is human health. Humans spend 90 per cent of the time indoors and therefore providing a healthy space should be the most important aspect of building design operation. Aspects of green building like providing good natural light, providing views of the outside, providing comfortable temperature and adequate fresh air ensure the occupants have a pleasant and productive space, which is in fact the "primary purpose" of any building.

Disclaimer: The views expressed in the article above are those of the authors' and do not necessarily represent or reflect the views of this publishing house