How does the project scale impact the overall approach to sustainability? This webinar looks at two high-performance buildings with very different scales and programs, designed by Studio Decode. The first is Puma’s flagship store, a 5,000 sft. retail space located in Bangalore, India. The second is the upcoming headquarters for the Karnataka Power Corporation Ltd. (KPCL), a 90,0000 sft. office space located in Raichur, India. In both cases, the clients were highly invested in achieving sustainability, with the help of passive design, building-integrated photovoltaics and low-energy cooling systems. Yet both required distinctly different approaches. In this webinar, the Principal Architect Meghana Dutta discusses her approach to achieving sustainable performance in these projects.
PUMA had a vision for a flagship store that went beyond the conventional green benchmarks. The team saw an opportunity for targeting net-zero in the retail section of the store. With the rooftop PV offering a maximum 28 KW of power, the team decided to work backwards to ensure the building’s load stayed within this limit. Another constraint was the site, tightly bound on two sides. The team used a combination of thoughtful design strategies and alternate systems to achieve the performance goals.
The building was recessed from its boundary and raised a little to allow in daylight, flush out hot air by stack effect and bring in fresh air into the cooling system. The fully glazed shopfront on the eastern side was shaded by a canopy that also doubles up a PV system.
Given that the location has a cool climate at least half the year, the building requires cool air only during the summers. The building uses an earth air tunnel (EAT) cooling system that supplies pre-cooled air during the summers and fresh air in the other months. Sensors in the Air Handling Unit detect whether the earth-cooled air requires further cooling. The challenge for the team was accommodating the EAT within the tight site.
While the building is not currently operating at Net Zero Energy, it’s well positioned to meet this target once the remaining PV capacity is added.
The KPCL Headquarter in Raichur is an ongoing construction, an office space for a state-run power plant township. This time, space wasn’t a constraint with a 5-acre site allotted for the project within the township. The challenge lay in coming up with a simple-to-construct facility, that would provide respite to the employees from the harsh working conditions and high temperatures in the power plants.
The final design consists of a simple column-beam structure, with passive features like courtyards, landscape, light shelves, double fins and a skin wall to prevent heat gain while providing daylighting. To counter heat gain from the ground, temporarily occupied spaces like auditoriums and cafeteria are placed on the ground floor while the upper floors are used as offices. The ground floor is cooled by an earth-cooling system while the upper floors are cooled by a vapor absorption chiller, that utilizes the steam generated in the site. 7.5% of the rooftop area has been earmarked for solar PV installation. The project is estimated to achieve an energy reduction of about 45% from the baseline.
For us, the discussion with Meghana stood out for her focus on qualitative goals. Sustainability is a goal that goes beyond achieving the numbers. It’s something that finally translates into a better experience of a space.
This webinar was conducted on 4th June 2019.
She is the founding partner of Studio Decode and leads the firm’s initiatives in research and implementation for their sustainable efforts. She has a Masters in Environmental Policy and International Development from Harvard University along with a Masters and Bachelors in Architecture.’
The courtyard sizing and location was done using lighting simulation. We wanted every work space to get natural light and outside views.
Q2. How was condensation in EAT and the resulting impact on Indoor Air Quality tackled?
We planned in advanced for this and advised our clients on the proper slope, support system for the pipes and other aspects for ensuring that the condensate was properly collected and pumped out. Filters ensured proper air quality. In PUMA, filtration was done after the air passes through the pipes while KCPL required double filtration on account of the poor air quality of the surrounding.
Q3. Was a study of Life Cycle analysis of materials done?
While we didn’t get into actual life cycle cost calculations, we ensured the use of local materials. In KPCL, fly-ash was a product of the thermal power plants and so we used fly-ash in the blocks.