Green buildings

Abstract

Global warming, energy crisis and depleting natural resources, created the need for the development of the concept for sustainability and made the environment more conducive to sustainable development. The three pillars of sustainability are economic growth, environmental protection and social equality. This concept of sustainability has trickled down in the construction industry as well and resulted in birth of the concept of ‗green buildings.The construction industry accounts for 40% of the world‘s energy consumption and accounts for 21% of greenhouse emissions. This importance of the sector can be understood by the fact that it contributes to around 12% of the country‘s GDP and is currently growing at a CAGR of around 10%. This notion of sustainability in construction and the need to focus on triple-bottom line maximization led to the evolvement of the concept of sustainable buildings, also known as ‗green‘ buildings. A green building is defined as a ―high performance delivering building- high on energy efficiency, life cycle performance and durability.‖ An ideal green building leaves zero foot-print on the environment in terms of energy usage, carbon emissions, waste generation and resource consumption. These buildings focus on key parameters like sustainable site selection, water, material and energy efficiency, and indoor environment quality. Green building are rated for their ‗greenness‘ based on certain parameters defined by different rating systems across the globe. These rating systems are tools wielded to evaluate the current or expected performance of a building on the whole. In India, the two important rating systems to certify green buildings are the LEED – India Green Rating System introduced by IGBC and the Green Rating for Integrated Habitat Assessment (GRIHA). The green building movement began in India with a modest foot print of about 20,000 square feet in 2003 when CII Sohrabji Green Business Centre received the prestigious LEED Platinum rating. This movement is expected to touch a magnificent milestone of 2 billion square feet by 2015 with participation from various stakeholders like the government & other nodal agencies, corporates, architects, product manufacturers and institutions. Still, there is a segment of builders and developers that eyes green structures with a level of skepticism primarily due to the cost premium green buildings command over normal building and its repayment as well as ambiguity. A cost-benefit analysis of green buildings shows that the skepticism over cost premium of the green buildings is often overstated and building green actually makes business sense. Though the first Indian green building cost 18% more than a similarly sized conventional building, the cost premium has come down significantly to 2-7% depending upon the level of sophistication. This additional cost is due to the additional measures that need to be undertaken to impart them the green characteristics. These structures return around 10 times more than they take over the entire life of the building.Although the upfront cost of green buildings is more, the savings accrue due to lower operating and maintenance costs as well as better efficiency of the building. The benefits that a green building accrues over its life time can be classified under two heads – tangible and intangible benefits of a green building. The tangible benefits are due to

1. Energy efficiency of the order of 30-40%

2. Material efficiency 3. Water efficiency 4. Waste Management

5. Carbon Credit Trading

The report shows that the use of solar panels and HVAC systems in the building can reduce the energy consumed by a building by around 30%. The intangible benefits include health benefits, differentiated positioning, improved productivity, better environment etc. As the construction industry started embracing the green building revolution, the government and administrative bodies too jumped into foray by incentivizing eco-friendly construction as well as making minimum standard adherence laws to promote green buildings. However, more intervention from government is required in form of policies, incentives and subsidies to promote green buildings. Pointers can be taken from policies introduced by countries like US that lay substantial emphasis on sustainable construction.The past 10 years have also shown that building green not only makes responsible environmental sense, it is also a respectable business sense. A billion square feet of green construction has effected a carbon dioxide reduction of the order of 12 million tons as well as resulted in the cumulative saving of 15,000 GW of energy savings and 45 million liters of water savings. An increase in the green footprint of the country will result in an increase in expertise level of the technical force, reduce inefficiency losses and induce economies of scale in green products thus reducing in the cost premium of a green building over a conventional one.