With climate change and urbanisation, much attention is focused on our consumerist lifestyle, and how all the waste we generate is destroying the planet and our children's future.
For a small city state like Singapore, a conversation on waste is particularly pertinent, given the shortage of land for landfills. It is also timely, with the projection that our only landfill at Semakau will be full by 2035, a mere 16 years from now.
Cities have become increasingly desensitised to the amount of waste that they generate. This is not helped by the explosive growth of e-commerce and food delivery services in recent years, which generate an enormous amount of packaging waste.
Based on data in 2011, the United Nations Food and Agriculture Organisation estimates that if food wastage were a country, it would be the third-largest carbon-emitting country in the world.
THE PROBLEM WITH 'INVISIBLE' WASTE
In Singapore, we have a clean and efficient waste management system built on the shoulders of our public-health pioneers, who ensured a high standard of environmental health. Alas, this has also made our waste problem "invisible".
Our trash "disappears" once we throw it into this magical hole in the wall known as the rubbish chute. Within a few days, most of it ends up as incinerated ash on Semakau Landfill, where the picturesque lush greenery and thriving wildlife further belie the urgency of the waste problem.
Discussions on the security and resilience of cities tend to focus on their food, water and energy needs. While these inputs are imperative to keeping any city going, outputs such as waste are also critical for land-scarce Singapore. Our waste infrastructure operates round the clock. It is constantly on the move, akin to a conveyor belt, carrying waste from households to Semakau Landfill. Without a landfill, the conveyor stops.
CIRCULAR ECONOMY APPROACH TO WASTE
To address our waste challenges, the Ministry of the Environment and Water Resources designated this year as the Year Towards Zero Waste and launched the inaugural Zero Waste Masterplan in August. The milestone Resource Sustainability Bill was then passed in Parliament to provide legislative framework for the measures in the masterplan.
The masterplan outlines Singapore's key strategies for becoming a zero-waste nation. As a society, we need to break away from the linear economy of "take, make, use and throw", and shift towards a circular economy, where resources are kept in use for as long as possible.
The masterplan focuses on three priority waste streams - e-waste, food waste and packaging waste, which includes plastics. There is a growing global momentum to reframe the waste challenge into an opportunity to create economic growth, while ensuring environmental sustainability.
A 2015 Accenture report estimated that the circular economy could unlock US$4.5 trillion (S$6.1 trillion) of global economic growth, driven by uncertainty in the future supply of many natural resources and the volatility of commodity prices.
Singapore has done well in closing its water loop, and is making steady progress in closing the waste loop too. While our overall recycling rate can be better than the current 60 per cent, we have done well with waste streams like construction and demolition waste, where the recycling rate is almost 100 per cent.
What is required to drive a circular economy? We can think in terms of three areas: ensuring sustainability in production, waste management and consumption. Efforts to drive such actions will require effort from the private, public and people sectors.
SUSTAINABLE PRODUCTION - MOVE UPSTREAM
First, for sustainable production, we need to start upstream.
In sustainability conversations, recycling may be most spoken about, but it is really the last resort. We need to relook the whole chain of resource flow to create circularity. For example, companies can design products that last longer, using materials that are easily recyclable.
Businesses can also offer services instead of physical products, and create a bigger sharing economy. Besides shared bicycles, other examples include sharing services for personal cars, umbrellas or even takeaway containers.
One way to incentivise companies to "design out" waste from their processes is to put the responsibility for the proper disposal of their end-of-life products on producers, via an extended producer responsibility (EPR) framework. EPR already exists in many European countries. Singapore will be implementing EPR for e-waste and plastic waste as soon as 2021.
Another way is to promote industrial symbiosis, where the waste output of one process or facility is channelled to another as useful input.
This requires upfront planning and industries agreeing to be sited closer together, which will also help to reduce land take.
This is the approach taken for the future Tuas Nexus, where the National Environment Agency's (NEA) waste management facility will be co-located with national water agency PUB's water reclamation plant. Co-digestion of food waste from the former with used water sludge from the latter will significantly increase the yield of biogas production, resulting in greater energy recovery.
SUSTAINABLE WASTE MANAGEMENT - RECOVERING VALUE FROM WASTE
Regulating the management of waste is a government responsibility, and recovering value from waste is a key strategy for becoming a zero-waste nation. This concerns the waste remaining after the 3Rs - reduce, reuse and recycle - which would ordinarily end up at incineration plants. This is where technology and innovation can make a difference, and turning trash into treasure can become a competitive advantage for Singapore.
An example is the treatment of incineration bottom ash to recover it for use as construction material known as Newsand, which is now in its field trial phase.
Another form of Newsand comes out of the waste gasification facility run by Nanyang Technological University, supported by the NEA. It is where municipal solid waste is turned into slag that can be used as road construction materials.
Newsand can potentially also be used for future reclamation projects. These efforts are supported by the $45 million Closing The Waste Loop grant launched last year to promote research and development in waste-to-value technologies.
The recycling of plastic waste is an area ripe for transformation. With increased demand for recycled plastics from fast-moving consumer goods companies and impending European Union regulations requiring a minimum amount of recycled content in packaging, Singapore is working on plans to develop the mechanical recycling industry here.
We are also exploring chemical recycling facilities, which are able to take in "dirtier" plastics of lower recycling value. These efforts will enhance our resilience in plastic waste management, increase our plastic recycling rate, and possibly spawn new economic value in green feedstock for the petrochemical industry.
The recycling of food waste is another exciting area that holds tremendous potential. An idea gaining traction is black soldier fly composting - where food waste is fed to black soldier fly larvae, with the resulting frass (insect excrement) used as compost.
With the impending regulations on food waste segregation, the cleaner source of food waste will help increase the yield extracted through these technologies.
SUSTAINABLE CONSUMPTION - WASTE NOT, WANT NOT
While private and government sectors clearly have a role to play in our zero-waste journey, the success of these efforts ultimately comes down to the people sector.
As consumers, our preferences and habits drive products and services - how they are sourced, produced and packaged.
As members of the public, our readiness to do the 3Rs will also have an impact on the success of policies and regulations. Our choices and views do matter - they have both a signalling and catalytic effect on producers, service providers and policymakers.
In fact, the potential for individuals to make a difference is often underestimated. Half the total food waste generated is from households, and a third of domestic waste disposed of is packaging. It shows the huge potential to reduce waste from households.
All that is required from us are small lifestyle changes, such as using reusable bags for grocery shopping, taking our own bottles or cups to meetings, asking for less rice or noodles if we are not likely to finish it, or just using a lunchbox or tiffin carrier for takeaways.
As for our physical possessions, besides recycling right, the first two Rs - reduce and reuse - along with other derivatives like repair, refurbish and repurpose, are equally, if not more, important for promoting circularity in physical goods.
We also want to encourage more to take ownership of our shared future by co-creating solutions with the NEA. The stakeholders can be businesses, such as the 59 partners at more than 1,600 premises that participated in the NEA's Say Yes to Waste Less campaign launched in June.
They can also be citizens participating in citizens' workgroups, such as the recent one on #RecycleRight or the upcoming one on reducing disposables. Societal groups and non-governmental organisations can also tap the Towards Zero Waste Grant to turn their zero-waste ideas into reality.
Even as this year draws to a close, our zero-waste journey continues, and is likely to gather pace in the years to come. Compared with just a year ago, the ground has shifted significantly, and sustainability is on the march.
One reference point is the reverse vending machine trial recently launched by the NEA - in just the first month of operation, the collection rate of bottles and cans increased more than 30 times, compared with a similar trial done a year ago. Another reference point is supermarket chain FairPrice charging for plastic bags at 25 of its outlets.
The pace of development in these environmentally conscious practices has exceeded most expectations.
Everyone can play a key role in promoting the circular economy by being more mindful of their consumption habits, and consuming responsibly. There is only one earth, and our children's future depends on it. Every effort counts, and it all adds up - we can start small, but we should start now.
• Tan Meng Dui is chief executive of the National Environment Agency.