SINGAPORE - Ways to reduce reliance on air-conditioning systems or make cooling greener were among the ideas shared by participants at a discussion on Sunday (Oct 24) about Singapore's long-term land use plans.

The discussion, organised by the Urban Redevelopment Authority (URA), focused on four areas - making Singapore inclusive; adaptable and resilient; sustainable; as well as distinctive and endearing.

These areas for discussion were distilled from feedback gathered in the first phase of the year-long public consultation on long-term land use plans, which took place from July to September, when more than 5,600 people were polled.

On Sunday, 60 participants were split into smaller groups to discuss ideas involving one of the four pillars, before reconvening to share their ideas.

Participant Adriale Pang said greener large-scale cooling methods could be considered amid global warming.

"In heat-stressed countries, there are growing calls to reimagine large-scale cooling methods and guarantee access to an environment with safe temperatures as a basic human right," said the 19-year-old full-time national serviceman.

"Singapore can take this opportunity to get ahead of the curve and design residential estates that do not have air-conditioning units in individual homes, but instead are cooled collectively with nature-inspired features like man-made streams and greenery-covered facades."

Others like Dr Winnie Choo suggested that architectural styles suited to the tropics could be applied more widely to reduce reliance on air-conditioning.

The 33-year-old doctor referenced colonial bungalows, which have higher ceilings that help dissipate heat, and Golden Mile Complex's terraced profile, which brings units natural ventilation.

"These could improve air circulation and reduce reliance on energy-intensive air-conditioning systems," said Dr Choo, who added that the steel and glass used widely in condominiums and skyscrapers today may not dissipate heat well.

Others said that heat removed from homes could be harnessed and used as an alternative energy source.

National Development Minister Desmond Lee, who hosted Sunday's discussion, said all these suggestions reflected the participants' desire for a sustainable Singapore.

He urged the participants to think of as many big and bold ideas as possible. "No idea is too wild to explore at this stage - remember that we are talking about 50 years or more into the future, and in 50 years, so much can change," he said, citing bold ideas-turned-reality such as the MRT network and Jurong Island.

One group suggested that to strengthen community ties, the minimum occupancy period, which dictates how long owners must live in their Housing Board flats before selling them, should be extended to a decade from the current five years. They felt a longer live-in period would allow communities to be built organically.

According to HDB's Sample Household Survey 2018, those who had lived in their towns for longer reported a higher sense of belonging.

Responding to this group, Mr Lee noted that the suggestion had immediately triggered a response from others on how it would affect social mobility, and added that the diverse views showed how each idea raised would have to be considered thoroughly.

Mr Pang suggested the Central Business District could be made more vibrant if office space were opened up for public use. Observing that the CBD appeared under-utilised after office hours, he suggested more could be done to achieve optimum occupancy throughout the day.

"With firms shifting work online and some vacating office space, it's exciting to reimagine buildings as being able to flexibly serve different functions at different times," he said.

"By broadening spatial considerations to include time as a planning parameter, a building could be an office in the day and a community space at night."

Sunday's discussion was the first of six facilitated discussions organised by the URA between now and December. Those interested in finding out more about the review, or registering for subsequent discussions may do so at this website.