The Indian Green Building Council (IGBC), in collaboration with the World Green Building Council and the United States Agency for International Development (USAID), has developed a new rating system called Net Zero Energy Buildings. In tandem with this initiative, the IGBC also launched a ‘Green Building Rating System for Hill Habitats’, which addresses the unique sustainability needs of urban development in hilly regions compared to cities on plains.
Green Building Congress 2018
In the 16th Green building Congress of 2018, this groundbreaking rating system was initially introduced, aiming to mesh seamlessly with the National Mission for Enhanced Energy Efficiency and the National Solar Mission. The event’s theme, ‘Green Built Environment for People & the Planet’, underpinned IGBC’s commitment to promoting the ‘Net Zero’ concept across India — an initiative that focuses on reducing annual energy consumption by 40-50% and cutting energy costs by roughly 30%.
Understanding Net Zero Energy Buildings (NZEB)
A Net Zero Energy Building (NZEB) is designed to produce as much energy as it consumes over the span of a year, primarily using renewable resource. Sometimes buildings that nearly meet this criterion are referred to as near-zero energy buildings. There’s even potential for a building to generate an energy surplus, which could then be sent back to the electrical grid. NZEBs are characterized by their energy-conscious design, incorporating a variety of features that operate without an energy source.
Contributors to Net-Zero Energy Design
Key examples of net-zero energy design include solar panels, heat recovery systems, geothermal heating and wind turbines. Passive solar gain can be utilized in cold climates by designing south-facing buildings with large windows; the inverse applies to the colder north side to minimize heat loss. In warmer seasons, passive ventilation systems can direct cool air upward from lower levels, venting it through the building’s peak. Rooftop systems could also be implemented to collect rainwater and decrease the usage of treated water.
India’s First Net Zero Energy Building
Indira Paryavaran Bhavan, located in New Delhi, holds the distinction of being India’s first net zero energy building. This project set a new standard for upcoming constructions with its adoption of solar passive design and energy-efficient building materials. The entire structure has been designed to be accessible to differently-abled individuals and is fully compliant with the requirements of the Energy Conservation Building Code of India (ECBC). Total energy savings of about 40% have been achieved through the adoption of energy-efficient air-conditioning systems and the use of green materials such as fly ash bricks, regional building materials, recyclable content, high reflectance terrace tiles and rock wool insulation for outer walls.
Necessity for NZEB and Green Building
In light of rapid urbanization, conceiving cities with a green framework right from the onset is indispensable. The vast impact of buildings on our environment, health, and economy is undeniable — something we cannot overlook.
| Fact | Number |
|---|---|
| Greenhouse gas produced by construction industry | 35-40% |
| Energy saved if all buildings in India were made green(according to TERI estimates) | more than 8,400 megawatts |
| Number of homes that can be lit by the power saved | 550,000 homes a year |
Green Building Certification Agencies
Several certifying agencies assist building developers in integrating green principles and attaining green certification. These include the LEED-India (Leadership in Energy & Environmental Design), IGBC Ratings, BEE-ECBC (Energy Conservation Building Code established by the Indian Bureau of Energy Efficiency) and TERI GRIHA (Green Rating for Integrated Habitat Assessment) among others. Each rating system provides an internationally recognized certification system for green buildings, setting energy efficiency standards for their design and construction.
