Zero Energy and beyond: NUS SDE4 attains Green Mark Positive Energy Award

You have booked a meeting room in NUS’ SDE4 where the rooms have their lights and cooling system powered down by default. As you enter the meeting room at the allocated time, you find that the room has been cooled at just the right temperature, comfortable for all attending the meeting.

Occupant thermal comfort in an indoor environment does not have to come at the expense of the environment, as SDE4 has demonstrated. The highly energy efficient building at the top of Architecture Drive was recently accorded the Building Construction Authority (BCA) Green Mark (GM) 2021 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.

“In decarbonising our campus towards carbon neutrality, reducing energy demand and minimising wastage is imperative, apart from passive design and active strategies. With SDE4 achieving Positive Energy status, we hope it will inspire other building owners and users to achieve the same and reduce their energy use in the fight against climate change,” said Mr Koh Yan Leng, NUS Vice President (Campus Infrastructure).

SDE4 is equipped with a multitude of sensors that measure Indoor Environmental Quality (IEQ) such as carbon dioxide, the level of particles in the air, temperature, humidity, light, sound level and room occupancy. These sensors provide relevant information for the smart Building Management Systems (BMS) and algorithms to monitor and manage the energy usage of the building, to further drive down energy consumption during operations.

Mr Bertrand Lasternas, Associate Director at the NUS College of Design and Engineering and Energy Manager of SDE4, explained, “The IEQ sensors and BMS enable us to track the actual meeting rooms and classrooms usage against bookings. This is to ensure that users are mindful not to book spaces that they do not use. The lighting, air-conditioning and other electrical equipment will be automatically switched off if no occupancy is detected, thus keeping down energy use. These strategies ensure that energy wastage is minimised on unutilised spaces.”

As a result of these efforts, SDE4 achieved an Energy Usage Intensity (EUI) of 45.5 kwh/m2/year compared to BCA’s reference EUI of 90 for the category of Super Low Energy buildings for Institutes of Higher Learning. In 2021, the building generated about 584,000 kWh of renewable solar energy while consuming only about 390,500 kWh.

SDE4 also boasts naturally ventilated spaces and an innovative hybrid cooling system which supplies 100 per cent fresh pre-cooled air, augmented by elevated air speed by ceiling fans to achieve a comfortable indoor thermal level for users. These features helped in managing the building's energy consumption and contributed to it achieving Zero Energy status.


By University Campus Infrastructure