Chennai to promote ‘expensive’ green buildings with extra FSI lure

CHENNAI: Since more than 70 per cent of Chennai’s greenhouse gas (GHG) emissions are from buildings and stationary energy, the State government has proposed to provide FSI (Floor Space Index) compensation for energy-efficient buildings.

According to the Chennai Climate Action Plan, released a few days ago, providing compensation for green buildings is one of the actions to mitigate climate change and its impact on the city.

Since builders are discouraged by the immediate costs involved in adopting green building norms, the action plan proposes to modify the general building regulations to add allowable deductions in FSI calculations against areas lost to energy-efficient improvements. It also suggests conducting a pilot study to assess the cost impact of compliance with ECBC (Energy Conservation Building Codes).

“The major strategies identified for the energy efficiency sector include moving towards renewable energy through the increasing capacity for solar power generation and hydroelectricity in the State, adopting enhanced energy efficient appliances and technologies, and incorporating ECBC and energy audits for buildings,” the action plan said.

In addition to providing FSI compensation, the action plan recommends the departments concerned mandate ECBC compliance and the formation of green building cells for monitoring all the new building approvals. Empanelment of the cadre of service providers for the construction and retrofitting of buildings to make them ECBC compliant and introducing economic incentives to enforce ECBC compliance.

Meanwhile, builders opine that providing FSI compensation will encourage more people to opt for green buildings. “One of the reasons for people not going for green buildings is the cost of construction. Builders are paying additional charges to avail of premium FSI. If the government can give that free of charge for green buildings, builders will opt for green buildings as they’re energy efficient too,” said S Rama Prabhu of Builders’ Association of India (BAI).

Though builders would take back the money they spent on green buildings in the long run, he pointed out that they’re discouraged by immediate costs. “If the government encourages FSI compensation, more people will choose green buildings,” he said.

As per data, Chennai has the second highest per capita emissions of GHG among metros. Every person in the city emitted 1.9 tonnes of carbon dioxide (CO2) equivalent during 2018-2019 (Mumbai emitted 2.0 tonnes of CO2 equivalent). Overall, the city emitted 14.38 tonnes of CO2 equivalent during the period.

In 2018-2019, the stationary energy (buildings) was responsible for 10.10 million tonnes of CO2 equivalent emissions.

Energy-efficient building norms on the anvil

The GHG emission by the transportation sector was at 2.37 million tonnes of CO2 equivalent and the waste sector at 1.90 million tonnes of CO2 equivalent, comprising 16% and 13% of the city’s total emissions, respectively.

Emissions from buildings are calculated based on grid electricity and combustion used. Among the buildings, residential buildings accounted for 44.4% of the total emissions while commercial and institutional buildings accounted for 37.5%. Manufacturing industries and the construction sector accounts for 15.3% and buildings of energy industries emitted 2.8%.

It may be noted that the city’s built-up area has increased to 67% of its total extent in 2021 when compared to 48% built-up area in 1991.

Meanwhile, the area of open land, vegetation and waterbody has come down to 12%, 17% and 4% respectively.

In 1991, around 21% of the city’s area was open land and 23% was vegetation. Waterbodies covered 8% of the land. The State Environment and Climate Change department

has already commenced the process of preparing energy-efficient and sustainable building norms, which will be incorporated into Tamil Nadu Combined Development and Building Rule, 2019.

Once they’re incorporated, the department will implement energy-saving measures in government and private buildings to reduce GHG emissions from energy production and consumption, along with the Municipal Administration and Water Supply, and Housing and Urban Development departments. The rules will mandate rainwater harvesting, sewage reuse, sustainable cooling system and minimal usage of water and emission during the construction phase.

Recently, a GO was issued directing the State Housing Board and Tamil Nadu Urban Habitat Development Board to start using energy-efficient and climate-resilient designs in their constructions.