Singapore's first public housing blocks built to be environmentally sustainable have become the testing ground for future projects.
From afar, the high-rises of Punggol Eco-Town look unremarkable, but they are the first large-scale experiment to make public housing eco-friendly in Singapore, a tropical city-state that is hot year-round.
Over 80% of Singapore's residents live in public housing, called HDBs, after the government agency that builds them.
"What we have done is that we put in various eco friendly features that helps in terms of capitalizing on the wind, enhancing greenery, reducing energy consumption, water usage, how to promote waste recycling, et cetera, all in one development," said Ng Bingrong, the project director, Treelodge@Punggol.
The eco-friendly methods range from commonplace and practical to highly innovative.
Plant-covered roofs naturally lower the buildings' temperature, and the towers' orientation, facing away from the sun, helps too. Painting the buildings white helps keep them cool and bring in sunlight.
But white walls also look dirty more quickly, so the government is testing self-cleaning paint, which breaks down grime as it is triggered by sun exposure.
Alan Tan, the director of HDB's Environment Sustainability Research team says the project's variety of experiments will have wider implications for future housing in Singapore.
"Punggol Eco-Town is in fact a living laboratory for us," said Tan. "This is where we test bed a lot of urban solutions for us to identify which of those are workable and for us to adopt, for us to introduce more to our public housing,"
Inside the apartments, tap water that goes down the drain is used to flush toilets. Solar energy powers elevators, lighting and water pumps.
And various indicators placed around the buildings, like the ones found in the elevators that show the amount of solar energy being outputted, provide constant reminders to the residents of the different lifestyle they are living.
But being eco-friendly comes at a higher price -- the sustainable buildings cost 7% more to build than traditional apartments.
The cost concerns have also sparked fiscal innovation, pushing the government to think of ways to make the eco-friendly features less expensive. One solution has been to lease, instead of buy, the building's solar panels from private companies.
"It's very difficult for the government to continuously provide the funding. So what we have done is that we will try to partner with the private industry," said Ng.
Under the scheme, the government subsidizes start-up costs, while the solar energy companies install the panels, maintain them and sell back the energy to the power providers to recoup their costs.