From radiation cooling towers to vertical gardens and geothermal insulation, here’s a look at how green buildings have taken off in India.
Buildings account for 8% of the total country’s utilization in terms of power and grow steadily at 11 to 12% an annum. This rate of growth of energy demand among buildings is much higher than the 6% growth that the electricity sector sees overall.
Most commercial buildings in India have an Energy Performance Index (EPI) of 200 to 400 kWH/sq. m/year. In contrast, buildings in Europe and America have an EPI of less than 150 KWH/sq. m/year.
For uninterrupted functioning, business cannot compromise on their energy needs. However, with India developing as a leading IT and services power house, there have been progress towards exploring and implementing sustainable alternatives for energy generation.
Here are 10 examples of amazing innovations that green buildings certified by the Indian Green Buildings Council (IGBC) have implemented to bring down their energy efficiency and costs significantly.
1. Solar Air Conditioning- Turbo Energy Limited, Chennai
The solar air conditioning in Turbo Energy systems in Chennai uses solar power to condition or control the air in the building by passive solar, solar thermal energy conversion and photovoltaic conversion in which sunlight is converted to electricity. The plant has installed the 90-TR hot water fired VAM system upto 26,000 sq.ft which has reduced the Heating Ventillation and Air-Conditioning (HVAC) electrical load by 117kW. In addition to this Turbo Energy India also has a working turbine of 5Kw capacity in position.
2. Earth Air Tunnels and Passive Cooling: Aquamall water solutions, Dehradun and Police Bhavan, IGP office, Gulbarga
Earth tunnel Air conditioning system also known as passive air conditioning installed in Aqualmall water solutions in Dehradun, is a wonderful utilization of nature. The system sucks in air from the outside and with the help of geothermal cooling the air is sent to interiors.
The IGP office in Gulbarga uses Passive downdraught evaporative cooling (PDEC) system where air passes through a layer of water in the wind tower. This cools down the water and that water is sent to the interiors of the building which is similar to the Earth tunnel air conditioning system.
3. Thermal Storage: TCS technopark and Grundfos Pumps, Chennai
After installing this system, TCS technopark in Chennai and Grundfos Pumps in Chennai have experienced a huge reduction in peak load in the daytime. This is achieved with the thermal energy systems which collect energy and store it for later use, even months later. This also works inter-seasonally where during winters it uses the solar heat collected in the solar collectors and during summer it uses the cold air conditioning obtained from the winter air.
4. District Cooling System – RMZ Ecospace, Kolkata
With the help of district cooling system RMZ Ecospace uses wasted heat from summer time, through combined heat and power generation units which integrate the production of usable heat and power to run absorption refrigerators for cooling. This method get a high CoP (coefficient of performance) which is more than 6.3.
5. Radiant cooling technology – Infosys, Pocharam campus
The Infosys Pocharam campus has an air conditioning system which is 30-40% more efficient than the conventional air conditioning systems. This is possible with the radiant cooling technology where a temperature-controlled surface cools indoor temperatures by removing sensible heat and more than half of the heat transfer occurs through thermal radiation. This has helped the coefficient of performance (CoP) spike up as high as 8.
6. Hybrid- HVAC system: Olympia Tech Park, Chennai
By effective usage of grey water in the building, Olympia Techpark in Chennai has able to meet its heating and cooling requirements. They have a dual plumbing line where the treated gray water is used for flushing or in irrigation. With a HVAC system they are able to have cool, indoor comfort when it’s hot outside providing a year-round indoor comfort solution.
7. Green and Solar Reflectance Index roof: Hotel Leela Palace, New Delhi
With roof covered with vegetation, Hotel Leela Palace, New Delhi and CII- Godrej GBC in Hyderabd have created artificially altered surfaces that can deliver high solar reflectance (the ability to reflect the visible, infrared and ultraviolet wavelengths of the sun, reducing heat transfer to the surface) and high thermal emitting (the ability to radiate absorbed, or non-reflected solar energy). Hotel Leela Palace in Delhi also has a Solar Reflectance coating which further mitigates local microclimatic conditions.
8. Lighting controls: Occulux sensors, Daylight sensors- RMZ Millenia Business Park, Chennai
RMZ Millenia Business Park in Chennai have seen a continuous saving in energy consumption. They have installed the Digital Occulux sensor that would dim-up and dim down the lights based on occupancy and daylight availability. They strategically use day-lighting and better lamps which adds to their savings.
9. Wind Hybrid Solar Charger: Suzlon One Earth, Pune
Suzlon One Earth in Pune and Delta Power in Rudrapur use a wind hybrid solar charger: a solar / wind hybrid system where solar and wind power production is used together so that the reliability of the system is enhanced. In addition, the size of battery storage can be reduced slightly as there is less reliance on one method of power production.
Suzlon One Earth in Pune has facilities to recycle all the water it uses, has roof gardens and generates 154 KW of energy on site through a combination of windmills and photovoltaic panels.
10. High Performance Envelope: ITC Royal Gardenia, Bangalore
ITC Gardenia in Bangalore has reduced heat gain to large extent by their design and have experienced serious energy savings. High performance Envelope includes cavity walls which has two skins of bricks with a hollow space in between which helps in slowly drawing rainwater or even humidity into the wall. The cavity serves as a way to drain this water back out through weep holes at the base of the wall system or above windows. This has also favoured the living walls that they have adopted by decorating the walls in interiors ith plants. They also have double glazed units which further stops heat loss.