The Hyderabad study tour kickstarted with a visit to the first platinum rated green building in India, the iconic Sohrabji Indian Green Business Centre (IGBC). With an EPI of 85 kWh/sq.m/yr, the centre exemplifies sustainable performance through thoughtful integration of passive and active measures. The building recently received an ambitious retrofit to target a net-zero energy facility. It now features a 124 kWp bi-facial photovoltaics and a highly efficient water cooled chiller system.
The tour was joined by 17 participants including professionals from the building industry as well as academia. It was led by Mr. Gaurav Pershad and Mr. Dhruva Ballal, both counsellors at IGBC.
The tour commenced with a description of the architectural features of the building such as the circular form with strategic chamfers for mutual shading, north-lighting panels to tap soft daylight, extended shading systems to cut-off glare and sloping roofs for the installation of PV panels. The participants also observed the rich bio-diversity on the site with respect to the flora and fauna.
The highlight of the building is the recently installed bi-facial photovoltaic panels, which have been used for the first time in India. These panels capture energy from both the front and back, thus enabling them to generate more energy compared to traditional PV panels. As per analysis conducted by the IGBC team, the efficiency of bi-facial panels supersede the efficiency of conventional panels by 4%-5%. The participants were led to the roof-top where they observed the various components of this state-of-the-art technology, including the orientation, size, material and transparency of the PV panels. Further, Mr.Ballal elaborated on the working of the system and how the technology is leveraged to tap more energy to meet the centre’s net-zero goals. For example, the roof has been coated with a high SRI paint to increase reflection onto the bi-facial panels.
Another important component of the building is the newly installed water- cooled screwed chillers for space conditioning. Two chillers, each of 49 TR function at a part load efficiency of 6.58 and supply cooled air to the regularly occupied spaces. The participants were given an opportunity to closely observe the various components of the chiller such as the cooling towers, pumps, Air Handling Units (AHU), evaporator and the various motors.
With an energy generation of 220 kW and a consumption of 200 kW, IGBC has demystified the viability of retrofitting to achieve a net-zero energy facility.