How digital twins are building a carbon neutral campus

By Yun Xuan Poon

Interview with Professor Tan Eng Chye, President of the National University of Singapore.

Trees have long featured in ancient myths as helpers and protectors. Hinduism tells of the wish-granting Kalpavriksha; the British Isles believed in trees that protect from evil enchantments; and the Yggdrasil tree from Old Norse legends literally holds up the heavens.

Trees in the modern world serve a much more grounded purpose. They give shade, lower temperatures and help to counter global warming. The National University of Singapore (NUS) hopes to plant 100,000 trees as part of its plans to create a carbon neutral campus by 2030.

It’s using digital twin models to find the best spots for trees to take root. GovInsider spoke with NUS President Professor Tan Eng Chye to learn how it is branching out for a green campus.

Carbon neutral campus

NUS plans to plant 100,000 trees over the next 10 years with the help of digital twins. The university is using 3D digital building models, geospatial tech and IoT to simulate and analyse the environment, so it can find the best homes for the trees, says Tan.

This vision ties in with the SG Green Plan announced earlier this year. Singapore declared that it would plant one million more trees, which would help cool the environment and reduce urban heat. NUS’s goal will contribute to 10 per cent of the nation’s target.

The university has also experimented with net-zero energy buildings. The SDE4 at the School of Design and Environment “only consumes as much energy as it creates”, Tan shares. It features a solar roof and a hybrid cooling system, and is designed to give extra shade.

Smart building management systems will aid in the university’s mission to become a carbon neutral campus by 2030 as well. It has upgraded meters across campus to monitor energy use and equipment performance.

This allows teams to detect faults ahead of time and administer “timely remedial action, as well as targeted reduction and prevention measures”, Tan says.

Renewable energy is another important part of the strategy. By end 2022, about 60 NUS buildings will use solar energy, notes Tan. It is focusing research on clean energy materials and systems, and waste-to-energy conversion.

Zero waste

NUS is working to become zero waste. It plans to create “zero-waste precincts” in student residences, cafeterias, and common areas. These will sort waste for recycling and reusing across campus, Tan shares.

Through this, the university aims to divert 90 per cent of campus waste away from incineration plants, with a near 60 per cent recycling rate for food, packaging, and e-waste, he says. It will also phase out single-use disposables in eateries.

On top of this, NUS is exploring circular economy measures to “recover energy and useful by-products”. One example is converting food waste into usable items.

One project transforms soy pulp into a superfood, according to the National Environment Agency, while another turns coffee grounds into alcoholic beverages. Cheers to that.

The university keeps tabs on waste data to track its progress towards zero waste. It has tagged bins with RFID sensors and fitted collection trucks with weighing mechanisms, says Tan.

All this information is pulled onto a dashboard, where facilities teams can see location-based waste and recycling data in near real time. They can then quickly identify and address anomalies, he notes.

Shaping behaviour

“At the heart of the plan is the drive to instill behavioural change throughout the campus community,” Tan says. He hopes to see students conscientiously sort and recycle their waste at student residences.

He also plans to use university grounds as a “living laboratory” to testbed green measures, he adds. For instance, NUS trialled a smart shower meter system in its student dorms to help reduce water usage.

As students shower, LED lights indicate how much water they’re using. “This allowed the researchers to investigate if real-time feedback would have an impact on water usage,” explains Tan.

The four-month trial in 2018 revealed that this saved about five litres of water per person on average. The university has since installed the smart shower meter systems in other dorm buildings.

Keeping it cool

NUS is also working to keep its campus cool. This will reduce energy consumption and mitigate against climate change, while adapting to rising global temperatures, Tan shares.

It will design its campus to encourage walking over driving, to reduce carbon emissions and improve air quality, he adds. “We are progressively upgrading building management systems to include more sensors and leverage AI technologies to improve indoor air quality in the most energy efficient manner.”

On top of this, NUS will build well-ventilated spaces into its buildings and connect them with more sheltered corridors. Designs will deliberately reduce the amount of energy needed to cool the building in Singapore’s sweltering summer climate.

The world is far from being out of the woods for mitigating climate change. But NUS has its feet firmly planted in its green campus vision, and has already sown the seeds to make it happen. It may soon reap the harvest.

Featured image of Professor Tan Eng Chye by the National University of Singapore.