Over the last decade, green buildings have sprouted up across the island from Jurong to Pasir Ris.
From just 17 in 2005, there are now more than 2,500 of these environmentally friendly buildings, making up around 30 per cent of all buildings here.
Dr John Keung, chief executive officer of the Building and Construction Authority (BCA), has been credited with the flowering of green buildings here.
Today, he is recognised for spearheading three masterplans to encourage green buildings and even won a global award in October, the 2015 World Green Building Council Chairman's Award.
However, initially, some people thought that he was moving too fast. "They told me: 'Look, you may be moving a bit too fast, the industry cannot catch up'," said the 62-year-old, referring to the other CEOs from the industry.
The CEOs, who headed firms in sectors such as construction, architecture and property development, feared that Singapore did not have enough people who could design a green building in a cost-effective way.
They also worried that demand was insufficient to justify entry into green building design and construction.
"I told them we will create the demand. We will make sure whoever wants to develop expertise in green buildings will have business, they can secure projects to do," Dr Keung told The Straits Times.
"The second thing I told them is that the BCA Academy will provide courses to train people in the industry to make sure they know how to design, build and operate a green building."
True to his word, he pushed for regulations that mandate minimum environmental sustainability standards for existing buildings and introduced incentives for developers to build or retrofit green buildings, among other strategies to create demand.
Partnerships were also forged with overseas institutes, such as one with University College London to offer a master's degree in green building maintenance. Other courses, including a diploma in mechanical engineering that focuses on green building technology, are also offered at the academy.
To date, the BCA Academy has trained at least 13,000 individuals, who Dr Keung calls "green-collar workers". The aim is train up to 20,000 by 2020.
Dr Keung, who has a Master of Science in town planning and a doctorate from the University of Wales in Britain, said he has been passionate about issues on environmental sustainability since his university days. He decided to push the green building movement in Singapore in a "big way" when he became the chief of BCA in 2006. The father of three had previously worked at the Urban Redevelopment Authority and Housing Board.
Dr Keung believed that Singapore had a role in sharing its knowledge with other countries in the region. As of September, the BCA has had more than 270 overseas applications from 75 cities in 14 countries for Green Mark certification - a testament of how it is taking the benchmark beyond Singapore's shores.
Dr Keung stressed that it makes business sense to go green.
A building with a Green Mark Platinum rating, which is at least 30 per cent more energy efficient than buildings without Green Mark certification, will get returns from its "green premium" - the extra construction cost to go green - in 21/2 to 61/2 years.
"You get back everything you invest to make that building green. And after that, whatever you gain year after year is a net gain," he said. "And a green building will also give you better indoor environmental quality and is a healthier building," he added.
Mr Lee Chuan Seng, emeritus chairman of engineering consultancy firm Beca Asia, said Dr Keung's efforts have made Singapore the leading nation in the region in delivering green sustainable buildings.
"John's relentless perseverance and, at the same time, (his) calm reassurance when things get tough, have been a great encouragement to BCA staff and industry partners."
But Dr Keung is not resting on his laurels. "I must say I am happy to see the progress, but if you ask my colleagues, they will know I am not exactly 'very happy' because we want to do a lot more," he said.
His target, and that of BCA, is for at least 80 per cent of all buildings here to be environmentally sustainable by 2030.
In the coming years, the BCA aims to shorten the payback period for going green and get energy guzzlers like data centres and supermarkets on board the Green Mark scheme.
It also hopes to get building users more involved in cutting energy consumption, and to make research breakthroughs to make buildings even more energy efficient.
Said Dr Keung: "All these are things we want. We intend to stretch our target and, in the longer term, achieve them."