Schneider

Special Project

Taking the LEED!

April 2013
Slated to be amongst the world's largest LEED-certified green hotel, ITC Grand Chola in Chennai is also recently certified with GRIHA's 5-star rating.

The LEED bug has bitten ITC Hotels, with Platinum already being the rating of choice for nine hotels in 2010-11! What's more, the company is pushing the envelope of its stringent green policy. Consider the fact that the Chennai-based ITC Grand Chola has not just bagged the IGBC LEED but GRIHA's 5-star rating as well, making the project, worth over Rs 1,000 crore, amongst the first five-star hotels to receive dual ratings. Philippe H Charraudeau, Vice President & General Manager, ITC Grand Chola, elaborates upon the hotel's green features in conversation with SHRIYAL SETHUMADHAVAN.

The brief

At ITC Grand Chola, the trend is more or less the same as other ITC hotels. To be in synch with the environment, we focus on four fronts: energy and water conservation, indoor air quality, material and waste management. The architect on this project is US-based SRSS (Smallwood Reynolds, Stewart and Stewart) and the green consultant is Delhi-based Environmental Design Solutions. Apart from the luxury quotient and requirement, we commonly look at three aspects: the National Building Code, Bureau of Energy Efficiency's ECBC (Energy Conservation Building Code) and the Platinum LEED certification. For ITC Grand Chola as well, our brief to the architect and consultant entailed just these three guidelines.

Energy guard

Energy efficiency has been considered in almost every part of the design. However, section-wise, it was a big challenge to ensure energy-efficiency features over the 16 lakh sq ft (built-up area) building. But we have followed and exceeded the ECBC. In terms of the lighting power density, where ECBC on an average says 1.1, we have gone much lower. We have also taken certain risks and adopted new technologies on an experimental basis. For instance, in our air-conditioning plant, we have adopted a technology - Hartmann LOOP - that probably has been done for the first time in India. This is an intelligent way of controlling air-conditioning plants taking into account the ambience, weather condition and comfort level. Apart from this, we have implemented another new technology - the digital hot water controller - to generate hot water. In a conventionally constructed hotel, there is a system of hot water storage tanks. This has been totally eliminated in ITC Grand Chola and replaced with a hot water generator that precisely controls the temperature, further minimising fuel consumption. Also, we have introduced a computerised oxygen control system to optimise combustion efficiency. If the hotel load is going down or occupancy goes down, the oxygen level is reduced proportionately. And as this is computerised, the control system delivers the exact percentage of oxygen required and the speed of the burner varies accordingly. Further, another technology adopted is the building management system (BMS). Through this, all equipment is controlled and scheduled centrally from a computerised network. Apart from this, LED lights have been used wherever feasible and a programmable dimmer control has been incorporated in most areas.

Chill-o-air

As for chillers, considering the size of the hotel, we have opted for high-efficiency chillers which use environment-friendly gas. Also, for cooling towers, considering the required efficiency, the best available equipment have been used. If the cooling towers are not efficient, it can affect the entire air-conditioning efficiency.

Water works

We treat both the grey and black effluents from the building in our sewage treatment plant, which is based on SBR (sequential bath reactor) technology, one of the latest methods of wastewater treatment. Sewage in batches is collected in multiple tanks, which are further treated for good quality water. This is further used for gardening, air-conditioning, in the cooling tower, restroom, etc. In future, as we graduate to one more level of water treatment, we plan to use this water for laundry purposes as well. Apart from this, our design for water efficiency is slightly more unconventional than conventional buildings. ITC Grand Chola has been separated into two zones for water supply. While in the upper floors, you need to pump water at high pressure; in the lower floors, water should be pumped at low pressure. To avoid wastage of water by supplying a common pressure across floors, we have two separate systems for pumping for each zone; this helps optimise pressure and save water. Also, low-flow fixtures have been fitted in the rooms and public areas; low-flow WPs have been fitted for flushing purposes; and, wherever possible, sensor-based taps and urinals have been fitted.

Air aware

As part of our integrated BMS, monitoring the CO2 percentage or concentration in areas likes banquet halls, restaurant, and lobby is essential. Hence, we have ensured that it is far below the recommended level. For this, sensors are placed in all areas. While the World Health Organisation recommends a limit of 1,000 ppm (parts per million) of CO2 in a place, above which it becomes unhealthy, we have kept it even below 500 ppm. At this level, fresh air is pumped in to dilute CO2.

Materials in use

The building has been clad with granite that is locally procured. In fact, stone masons and artisans from the Mahabalipuram area were camping here for about one-and-a-half years to execute the work with local stone. Also, flyash bricks have been used. Flyash is basically rejected material from thermal power plants. The excavated earth has been recycled and reused to fill up the gaps at the site. Further, low-VOC paints have been used throughout the building along with roof paints. The exposed area of the roof is coated with SRI (solar reflective index) paints, which reflect most of the solar radiation that directly comes into contact with the roof. This helps reduce the heat of the building, avoiding any additional load on the air-conditioning. Apart from this, a standard under deck insulation has been done. What's more, multi-glazed windows have been used. These not only come with the heat block property but are an ideal trade-off between noise limiting ability and energy conservation capability. It's a triple-glazed window with one air layer in between. This air layer is provided deliberately to act as the heat block or insulator.

Making of a marvel

One thing that stands out about ITC Grand Chola is its sheer size. So implementing LEED to the Platinum level and now to the GRIHA 5-star level was a challenging task, which we achieved. However, in the case of utilising solar energy, work is still on.

We look forward to installing a hot water generating solar plant with a capacity of 20 kl per day, ie, 20,000 l/day. Accordingly, the fuel saving will be about 120 litre of diesel per day.

Project details:

Project: ITC Grand Chola, Chennai
Certification: IGBC's LEED Platinum and GRIHA 5-Star
Size: 8 acre, 16 lakh sq ft (built-up area)
Costs involved: Over Rs1,000 crore
Completion date: September 2012
Architects/planners: Smallwood Reynolds, Stewart & Stewart (SRSS). Tel: +1
404-233-5453. Fax: +1 404-264-0929. Website: www.srssa.com
Landscape architects: Belt Collins. Tel: 808 521 5361. Fax: 808 538 7819. Website: www.beltcollins.com
Green Consultant: Environmental Design Solutions. Tel: 011-2614 7085. Fax: 011-4056 8633. E-mail:info@edsglobal.com. Website: www.edsglobal.com
Services, electrical and plumbing consultants: Spectral Services. Tel: 0120-404 9000. Fax: 0120-404 9001. E-mail: info@spectralservices.net. Website: www.spectralservices.net
Elevators and escalators: Mitsubishi Elevators. Tel: 0124-463 0300. Fax: 0124-463 0399. Website: www.mitsubishielectric.asia/india/
HVAC Contractor: ABB. Tel: 080-2294 9129. Website: www.abb.co.in

Philippe H Charraudeau's perspective

"As far as green buildings are concerned, Indians are far ahead. For instance, 90 per cent of all green buildings globally are present in India. Also in terms of Energy Conservation Building Code, the ministry is now considering making it mandatory. Green ratings will become mandatory, similar to the BEE label on products as far as energy is concerned. At ITC as well, we are generating much more than what we consume. We have installed six big wind turbines outside Chennai. This amounts to a total 12.6 MW capacity and in the past year they have produced about 2.6 crore units of electricity, which is more than what we consumed. Also, we have entered into a Energy Wheeling Agreement with TNEB."

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