For energy-efficient buildings

A couple of years ago, while driving on NH-24 from Delhi to Gurgaon, a senior colleague commented that the stretch signifies what modern India will look like! However, he added that the buildings that are coming up on either side of the highway makes one feel that we are in North America or Europe. The glass façade that most of these buildings have used makes them stand out — all of them, however, miss the critical point that architecture has an inherent climate element.

While glass exteriors make sense in colder climates as they absorb heat and reduce the heating load, in India, they act as heat sinks, in turn, increasing the cooling needs of the building. The long lifespan of buildings ensures that such inefficiencies are perpetuated for years together, and the opportunity to intervene through retrofits is limited. There is, therefore, an urgent need to use resources efficiently for construction of buildings.

Resource efficiency in building construction is nothing new, given India's rich, traditional architectural knowledge. Many old buildings and monuments are the embodiments of such knowledge, with solar-passive orientation, insulation by use of mud, chequered windows to ensure natural ventilation, and huge courtyards.

One of the many such examples of traditional Indian architecture is the Amber fort in Rajasthan built in 1772. The building design had to overcome climatic challenges such as scarcity of water, and the hot, dry climate.

Its response was to ensure the use of natural light through large courtyards, leave open spaces for constant flow of air in the building, and make jalis or chequered windows that serve the dual purpose of privacy as well as ventilation. This fort, like countless others, is built in harmony with the natural habitat, reducing the requirement of energy for enhanced comfort.

REDUCING CARBON EMISSIONS

The buildings sector has emerged as a focal point in the international discourse on efficiency as a climate mitigation tool. The long lifespan of buildings significantly enhances the impact of interventions for energy efficiency. The Expert Committee on India's Low Carbon Growth Strategy set up by the Planning Commission, in its recent report, reiterates the importance of energy efficiency of buildings and its potential impact on Greenhouse Gases (GHG) mitigation, as well as energy conservation.

The Expert Committee takes note of the rapid growth in the building sector and sets its focus on the commercial building segment. This segment is likely to witness an exponential increase and is expected to grow from a little over 4,500 million square feet in 2005 to over 15,000 million square feet in 2020 and to 30,000 million square feet in 2030. Energy use by commercial buildings is much more than that by the residential sector. Stimulating construction of energy-efficient commercial buildings, the report adds, could help mitigate 60-120 million tonnes of GHG emissions by 2020, which could rise to 440 million tons of GHG emissions by 2030.

BUILDING CODE

With the goal of encouraging building energy efficiency and moderating energy consumption, the Government of India introduced the Energy Conservation Building Code (ECBC) as a voluntary effort in 2007. The code, developed by the Bureau of Energy Efficiency (BEE), covers the following components for commercial buildings that have connected load of 500 KW or more: Building envelope (what separates the interior and exterior environments of a structure); lighting; heating, ventilation and air conditioning (HVAC); service water heating; electric power and distribution.

ECBC has been evolved to reduce energy use in a building without compromising on comfort and occupant productivity. It lays down standards for energy use for various types of buildings in all the five climatic zones in the country.

Under the Energy Conservation Act, 2001, the Government is empowered to make ECBC standards mandatory, in consultation with the states. The strategy adopted by the Government is to integrate energy-related issues in the National Building Code, as well as encourage their adoption by various states. This would mainstream the adoption of energy efficiency in building design and construction.

In addition, there are two other initiatives in the buildings sector. They are the GRIHA rating system developed by TERI and adopted by the Ministry of New and Renewable Energy; and the LEED rating of the Indian Green Building Council. Both these ratings include all aspects of ECBC — they go beyond to look at issues such as water conservation and waste management.

The Government of India has adopted ECBC in all new building construction to take the lead. Energy-efficient building design ensures that the energy use of the building is reduced at least by 25-30 per cent. The additional cost incurred by developers for energy efficiency is usually less than 10 per cent, which gets recovered many times over due to the operations of the building.

EXISTING BUILDINGS

The codes are applicable to new buildings. There is also a need to tackle the existing stock of buildings, though the flexibility in retrofits is far less. This could be done by encouraging energy-efficient lighting. The key factor that needs to be overcome is the issue of split incentive in the building sector. Majority of building developers are not the users of buildings; similarly most users of existing buildings are not concerned with investing in energy efficiency.

In order, therefore, to encourage building energy efficiency, there need to be targeted policy measures. BEE has introduced the STAR labelling programme. This enables buildings to implement energy-efficient retrofits and reduce their energy bills by 25-30 per cent. The payback period for return on investments is usually three to five years. The labelling programme also provides an instrument for policymakers to develop incentive-based programmes.

In light of this robust policy framework for making new and existing buildings energy-efficient, suitable incentives could be structured to scale up. Economic incentives, coupled with awareness and information dissemination, could see a rise in demand for building energy efficiency. This could provide inducement to the building industry to invest in efficiency measures.

Some of the measures that could be implemented by the Electricity Regulatory Commissions to encourage energy-efficiency in buildings are:

Rebate in tariff for energy-efficient buildings by the electricity utility.

Discounts in property registration rates for energy-efficient buildings.

Lower interest rates for loans taken by consumers for purchase of energy-efficient buildings.

The building sector has the potential to reduce energy use on a long-term basis that will also lead to sustained GHG emission mitigation. Policies and measures, backed by targeted incentives, need to be ushered in to unlock the potential. The good practices in heritage buildings need to be rediscovered in modern architecture.

(The author is Programme Officer, OzoneAction Programme, UNEP, Bangkok.)

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