SINGAPORE: When it comes to going “green,” Singapore is the leader in Southeast Asia.

Last week, the island-nation officially inaugurated its Zero Energy Building (ZEB), the first of its kind in the region. ZEB is a 4,502-square meter retrofitted building located at the Building and Construction Authority (BCA) Academy complex. The retrofitting of the three-story former workshop started in end-2007, Tan Li Sirh, senior development officer of BCA’s technology and innovation development department, said.

The building harnesses mostly solar energy and also abounds of energy-saving features.

“ZEB is powered by 100 percent clean, renewable energy,” she said.

The building has high-performance solar photovoltaic panels—found mostly on the roofs, and even on walls surrounding the stairs—that can generate about 207,000 kilowatt-hours (kWh) of electricity annually.

Tan told reporters that about “three hours of good sunlight” would be enough to supply the building’s energy requirement for a day.

She said that at nighttime and during instances when there is no available sunlight—such as during the foreign media’s visit to ZEB when it was about to rain—the building can tap energy from the grid.

“ZEB can still do a normal thing [source energy from the grid supply],” she said.

But once the sun shines again, the building automatically switches to tapping solar energy, Tan said.

While ZEB would still get energy from the grid from time to time, the building would still have a net zero energy consumption output from the grid annually since the amount of solar energy collected and used cancels out the energy utilized from the grid, Tan said.

Excess energy collected by the building is also spread out to other facilities inside the complex since it cannot be stored.

“Solar energy storage is not cheap. We’re still undergoing research and development work on that,” Tan said.

A monitor at the building lobby shows real-time data collected since October 18. So far, the monitor indicated that the amount of solar energy collected and used is more than those from the grid.

Besides solar panels, situated all over ZEB are features that make use of natural lighting and ventilation to save energy like “daylight collectors”, shading systems and highly reflective mirror ducts that bounce sunlight into the interiors so that less artificial lighting is needed. These also include solar chimneys that suck out warm air; various plants that shade the walls to bring down indoor temperature; and a rooftop garden.

ZEB boasts of more natural lighting, automatic light level adjustment, displacement cooling and personalized ventilation. This allows the building to do without air conditioning units in several parts of it.

Loh Teng Siang Matthew, BCA senior communications officer, said retrofitting the existing building cost about 11 million Singapore dollars (about P372 million), or 5-percent more without the energy features.

Yes, quite expensive. But they estimated that ZEB is up to 50-percent more energy-efficient and would allow savings of about 84,000 Singapore dollars a year in energy costs compared with a building with a similar layout.

At present, various offices and classrooms are housed at the ZEB, as well as laboratories where further studies are being conducted. Tan said ZEB is a “life lab” as it serves as Singapore’s test bed for integration of green building technologies and design features in existing buildings.

Loh said they may consider further improvements on ZEB’s design and features in the future, depending on their research findings and upcoming new technologies.
Ben Arnold O. De Vera