The new state assembly, costing almost $95 million and inaugurated in March by Indian Prime Minister Manmohan Singh, is the first legislative building to get the “Gold” rating by the Indian Green Building Council (IGBC) under the Leadership in Energy and Environmental Design (LEED) Green Building Rating System developed by the US Green Building Rating Council.

The rating is for the energy saving measures in design and construction of the six-storied structure in Chennai.

Designed by GMP, a German architectural firm that won a global competition, it is an elliptical structure with four internal circles and six external semicircles with a covered driveway skirting it.

It was a race against time for all those involved in the project, with Tamil Nadu Chief Minister Muthuvel Karunanidhi announcing in January that the budget for fiscal 2010-11 would be presented in the new complex.

“The structure is built for the 21st and 22nd centuries. The design should be truly modern and not pseudo-modern,” said Ravinder Joshi, chairperson of Pune-based Archivista Engineering Pvt. Ltd., GMP’s Indian associate.

“Domes are an inseparable part of legislative buildings - whether in India or outside. So the dome has been incorporated in the Tamil Nadu Assembly building as well,” said Joshi while discussing the majestic 100 ft dome. The design also incorporates local features like courtyards and carvings on the facade and columns.

“The building’s shape and exterior cladding has been designed as a smooth arc which gleams obliquely against the linearity of the neighborhood as against a standard block construction, and helps reduce the direct heat radiation on the building thereby reducing energy consumption,” said Deepa Sathiaram, executive director of green building consultant En3.

Interestingly, for a building of the 21st and 22nd centuries, it also adheres to Vaastu, the traditional Indian design methodology.

Special care was taken not to disturb the existing structures and trees on the vast Omathoorar Estate where the building has come up. “Several trees were saved by transplanting them. The entire site has been well planned with lots of open and landscaped spaces to promote biodiversity. There is 340,000 sq ft of green space available inside the assembly complex,” said Sathiaram.

It has been designed to “harvest” natural light and to reduce heat to save on power. “There is a good amount of open space for harvesting natural lighting and air. Sunlight is harvested in the assembly hall through the dome,” said Joshi.

“The external building face is covered with structural glazing and granite cladding to allow natural light and prevent heat. The public area before the assembly will have a big fountain which will help to cool the area when there is breeze,” he added. Sathiaram adds that reflective paint has been used on the roof. “Now 80 percent of the heat will be reflected back thereby lowering the air conditioning by nearly seven percent,” she said.

In addition, roof gardens and air chillers will cover a large portion of the open terrace. Sensors installed inside the building will detect the presence or the absence of humans and will automatically switch lights and the air conditioning system on and off thereby saving power.

Savings in power consumption are around 20 percent as compared to other buildings of this size, according to initial estimates.

The next eco-friendly measure is the reduction of water consumption, particularly in a city where water is a precious commodity. All the water is recycled through sewage treatment plant installed inside the premises. The plant recycles 250,000 liters a day. Landscaping areas have been planted with native and adaptive species of vegetation, which require little or no irrigation after a few years thereby reducing the water requirement significantly.

Besides, the makers have gone for air-cooled chillers instead of water-cooled ones. Choosing water efficient fixtures such as low flow dual-flush toilets, sensor based urinals and hand washes, and reusing treated water for flushing the building has reduced overall water consumption by over 52 percent.

Measures have been taken to harvest rainwater to the maximum.

To get the green rating, Sathiaram explained that the material used had to be eco friendly too. “Paints, adhesives, coatings and other items selected for use in the building have less volatile organic compounds (VOC). You will not smell the fresh coat of paint,” she explained.

There is more. Low ultra violet glass has been used to allow only light and minimize heat. The composite wood products used don’t contain urea formaldehyde that can be potentially harmful to health. Only jute carpets will be used inside the building. The carbon footprint was reduced to a large extent by sourcing materials nearby and recycling construction debris inside the site. Contracts were signed with waster merchants to collect segregated paper, glass, plastics and other wastes.

“On the construction side, cement usage was largely reduced due to post-tensioning technology in beams and slabs instead of conventional reinforced cement concrete,” said S.A. Mohamed Mohideen, director of East Coast Construction and Industries Ltd.

Though the building has yet to be fully completed, the administration is looking to going green with other projects as well. “This building will create awareness about the green building concept. We will now keenly look at the prospects of going green with our other buildings as well,” said P. Natarajan, superintending engineer at the Public Works Department.