Bengaluru: NGT wants to assess carbon footprint of city’s glass-facade buildings

There are concerns that glass-facade buildings can reflect solar radiation into surrounding areas. Credit: DH File Photo

The National Green Tribunal (NGT) has taken note of the concerns regarding the environmental impact of glass facades covering buildings in Bengaluru.

It has issued a notice to several departments and requested a detailed report from the State Environment Impact Assessment Authority (SEIAA).

The tribunal was hearing a petition by Jagan Kumar J, who presented studies by IISc flagging the high carbon footprints of glass facade buildings and the bird kills they had caused.

Going by the rule, SEIAA considers the environmental impact of large buildings and lays down conditions while giving Environmental Clearance (EC). Kumar submitted two ECs issued by the authorities in 2016 and 2019.

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While the first EC restricted the use of glass to 40 per cent of the exposed area “to reduce electricity consumption and load on air conditioning”, the second one did away with the condition.

The petitioner submitted a study conducted by Prof T V Ramachandra and the Energy Wetlands Group at the Centre for Ecological Sciences, Indian Institute of Science. Published in 2016, the study found that per capita electricity consumption in areas dominated by high-rise buildings with glass facades ranges from 14,000 to 17,000 kWh per year, while in zones with eco-friendly buildings, it ranges from 1,300 to 1,500 kWh per person per year.

The use of lighting and air conditioning increases the buildings’ carbon footprint, while air conditioning units have been found to emit chlorofluorocarbons (CFCs) detrimental to the ozone layer.

The NGT took note of the concern that glass facade buildings can reflect solar radiation into the surrounding areas and directed the SEIAA-Karnataka to submit a detailed report with a scientific analysis of the issue. It also asked for an explanation as to why different rules were applied in the two clearances.

It also issued notices to the Department of Forest, Ecology and Environment Science, the state and Central pollution control boards and the Bureau of Indian Standards.

The petitioner also highlighted a report from the NYC Audubon, a community dedicated to the well-being of wild birds, which estimated that at least 90,000 birds crash into buildings in New York every year, with reflective glass being the primary culprit.

Kumar said he had approached the authorities to ban or restrict the glass facade but got no response.