The National University of Singapore’s extension for the School of Design & Environment (SDE 4) is an outstanding net-zero energy building in the tropics. The five-story building accommodates labs, design studios and workshops for the schools of architecture and interior, landscape and product design. As a school with an emphasis on energy-efficient technologies, the extension had to embody the principles it espoused and had to be an example to the students, faculty and extended design community. The building demonstrates that occupant thermal comfort in an indoor environment does not have to come at the expense of the environment.
Transsolar guided the design team through seven design charrettes to create a building that serves the various programs while remaining comfortable and energy efficient. Transsolar supported the design team with simulation tools for thermal comfort, daylight, glare and energy as well as with measurements of thermal comfort. This resulted in a contemporary architectural design which demonstrates a deep understanding of the tropical climate of Singapore. The design incorporates a large overhanging roof, which together with the West and East façade structures, shades the building from the sun’s heat and provides a cooler interior. 1,200 solar PV panels installed on the roof harvest enough solar energy to cover more than the building’s annual demand.
An optimized building design enables efficient cross ventilation and good exposure to daylight. Integral to the concept of net-zero energy consumption is the need to rethink conventional air-conditioning, which typically accounts for up to 60% of a building’s total energy load in a tropical country. This resulted in the design of an innovative hybrid cooling system that ensures rooms are not over-cooled. Rooms are supplied with cool air at higher temperatures + humidity levels than they would be with a conventional system. This cooling strategy is augmented with elevated air speeds from ceiling fans. Electricity consumption is reduced by opening windows when the weather permits and by air-conditioning only where needed.
As a result of these efforts, SDE4 achieved an Energy Usage Intensity (EUI) of 45.5 kWh/m²a compared to an EUI of 90 for the category of Super Low Energy buildings for Institutes of Higher Learning in Singapore. After 2 years in operation, in 2021 the building attained the Building Construction Authorities (BCA) Green Mark (GM) in Operation Platinum Positive Energy Award. This honour goes to signify that SDE4 is a best-in-class energy performing building with at least 115 per cent of its energy consumption supplied from renewable solar energy on its rooftop – a step up from the BCA’s GM Platinum Zero Energy certification that SDE4 attained in 2019.
2019 DGNB Klima Positiv
2019 WELL Certified™ Gold
2020 DGNB Klima Positiv
2020 International Living Future Institute Zero Energy Certified
2021 BCA Green Mark in Operation Platinum Positive Energy Award