Net-Zero Buildings See A Rise But Lack Govt Guidelines, Regulations
Mar 1, 2023 | Pratirodh Bureau
The net-zero DRI building in Manesar, Haryana. Net-zero buildings use solar or any other renewable energy sources to offset their annual energy requirements (Image: DRI)
Badriya Juma Masjid is a mosque at Kundapur in Udupi district in Karnataka spread over an area of 15,000 square feet. Unlike other popular mosque designs, this religious building has a different look. The L-shaped mosque has a wind turbine at the top of its building and solar panels on the rooftop. This is one of the selected net-zero energy buildings in India, rated by the Indian Green Building Council (IGBC), last year.
“Since the design phase, we started to construct it in a way that can reduce our energy requirements. We ensured taking all measures to increase our energy efficiencies like ensuring adequate daylight enters the building, using building materials that helped in adequate insulation of the walls and roofs,” Syed Mohammad Beary, founder of Beary Groups who built the mosque, told Mongabay-India.
The earlier assessed total energy requirement of the building was estimated to be around 25 KwH (Kilowatt-hour), but Beary said that with energy efficient measures, it was reduced to 7.5 KwH which is now catered with its solar rooftop (6 KwH) and wind turbine (1.5 KwH).
Meanwhile, in the north of the country, in Manesar in Haryana, close to New Delhi, the manufacturing plant building of Desiccant Rotors International is another example of a net-zero energy building. The firm manufacturing unit produces heat-recovering units, used in air conditioning. The building is spread in 200,000 sq. ft area and was constructed in 2019 and soon the features of net-zero energy buildings were imbibed.
“We have a connected load demand of 50 KW and we also have a solar system that generates this amount of energy. We have designed the building in such a way that the requirement of electricity during daytime is reduced and with more energy efficient measures we reduced the total load of the building,” Rahul Aeron, Vice President (Sales) from the firm told Mongabay-India.
There are several other net-zero buildings in India. Some of them include the Paryavaran Bhavan of the Ministry of Environment and Forests, Jaquar headquarters in Manesar, Akshay Urja Bhavan in Haryana, Godrej Plant 13 Annexe in Mumbai, Grid Corporation of Odisha building, among others.
Architects and sustainable building experts from the country claim that there is no clear definition of “net-zero building” in government rulebooks. They said that in real estate parlance, net zero energy buildings refer to such buildings which are producing the same amount of non-fossil fuel energy that they consume from the grid annually. However, private rating agencies have stricter norms for net-zero buildings where energy efficiency designs are also taken into account.
“There is no clear definition of net-zero buildings in India from the government side. There are several concepts of net-zero buildings. It could be net-zero carbon building, net-zero water building, and net-zero waste building. But usually in the building ecosystem, in general terms, net-zero refers to net-zero energy buildings where the total amount of energy required in the building is compensated by the total amount of electricity produced by renewable sources of energy,” Rishabh Jain, an architect specialising in sustainable buildings told Mongabay-India.
Ratings And Norms For Net-Zero Energy Buildings
Currently, there is a dearth of any government guidelines, building codes and regulations on net-zero buildings in India. The Model Building Codes of 2016 deal with the concept of ‘Sustainable and Green Buildings’. The Code mandates that buildings spread in areas beyond 100 square meters, should have provision for solar energy, solar water heater, and other green building norms like rainwater harvesting, energy efficiency, and others. But it does not talk about net-zero buildings.
The Energy Conservation Building Code of 2017, released by the Bureau of Energy Standards (BEE) makes it mandatory for commercial buildings with connected loads with more than 100 KwH to make provision for reserving a minimum of at least 25 percent of roof area for renewable energy and ensuring one percent of their peak demand from renewable energy. It also talks about making passive design strategies in designing buildings which can increase the energy efficiency of such buildings.
The Ministry of Power in 2021 also started rating net-zero buildings with its Shunya scheme where the BEE gives certification of net-zero buildings. This is given if the buildings can offset their building energy requirements with renewable energy. Buildings producing renewable energy equivalent to their total consumption get a Shunya (net-zero) label whereas those producing more renewable energy than their connected load get a Shunya Plus rating from BEE. The documents of BEE certification for net-zero do not account for energy efficiency while granting net-zero rating certifications.
The BEE, which rates net-zero buildings, defines such buildings as “…that relies on renewable sources to produce as much energy as it uses, usually as measured over the course of a year.” It does not take into account energy efficiency, building design, thermal comfort and other architectural parameters as accounted by other rating agencies like IGBC.
BEE claims it has around 100 rating certifications under different stages of consideration for net zero buildings. Emails sent by Mongabay-India to BEE for more comments on the issue didn’t evoke any response till the time of writing the report.
IGBC Ratings For Net-Zero Building
The Indian Green Building Council (IGBC), a part of the Confederation of Indian Industry (CII) which was earlier known for rating Green Buildings in the country, started rating “net zero ” buildings in 2018. The IGBC rating, which is intent oriented and voluntary in nature, rates net zero buildings based on their usage of renewable energy, energy efficiency, passive design strategies, and thermal comfort (comfortable room temperature). It gives merely 25 percent weightage to the use of renewable energy and focuses more on energy-efficient designs and other architectural parameters.