21 OCT 2020

Laying the foundation for sustainable cities

How can we enhance the liveability, sustainability and resilience of our cities through urban planning and urban innovation? 

Solar panels fitted on rooftops of public housing in Singapore help to power common services for the estate using renewable energy

Globally, cities occupy just 3% of land but produce a disproportionate amount of the world’s waste (50%) and greenhouse gases (60-80%). Cities also consume 75% of natural resources and use 80% of the world’s energy. Given that the proportion of the world’s population living in cities is projected to increase even further – from 55% today to nearly 70% by 2050 – the resource challenges and environmental impact of cities will only continue to accelerate.

Since cities are made of interrelated systems, the sustainability challenges faced are also complex and interconnected. A systems approach is needed to ensure that cities develop more sustainably, even as they grow in size and economic activity.

Speaking at an Ecosperity Conversations webinar by Temasek on 24 June 2020, Dr Limin Hee, Director of Research at Singapore’s Centre for Liveable Cities (CLC), said that sustainable districts can pave the way for cities to achieve high economic performance while achieving greater liveability and sustainability. The second speaker, Mr S Harsha, Managing Director for Sustainable Energy Solutions at SP Group, agreed that districts can be testbeds to integrate urban eco-innovations such as district cooling, renewable energy generation, batteries, electric vehicle charging stations and other digital applications. At district scale, the benefits are magnified and business innovations such as ‘energy-as-a-service’ can be more impactful when adopted.


Applying a systems approach in the Singapore context

Singapore was able to overcome high levels of unemployment, pollution and a lack of clean water and amenities because its early leaders believed that sustainable development and economic growth must go hand-in-hand. They took measures to create a highly liveable city despite its high population density. In 2019, Singapore was ranked the top city in Asia in Mercer’s annual global quality of living survey.

The development of a sustainable, liveable and resilient city was achieved through a systems approach to urban planning, governance and innovation.

Today, climate change and resource scarcity are increasingly pressing issues for countries and cities globally, including Singapore. They require innovations and spatial design for more sustainable urban growth. This includes decoupling carbon emissions from economic growth through more energy- and resource-efficient technologies, and a greater adoption of renewable sources. The Sustainable Singapore Blueprint outlines some of CLC’s aspirations for how Singapore can do so by setting key targets in green and blue spaces, mobility, resource sustainability, air quality, drainage and community stewardship. Improvements in these areas build on both infrastructural and human capabilities to make Singapore a more sustainable city.

Singapore has also gone further by turning vulnerabilities into strengths. Singapore’s water industry development and urban systems innovations such as NEWater, the Deep Tunnel Sewage System and Active, Beautiful, Clean (ABC) Waters have shown that translation and deployment at scale is possible. As a single agency, PUB, Singapore’s National Water Agency, can manage and scale up the translation and integration of urban systems innovations related to water, with clear leadership, good governance, research and development, and by working closely with the industry. 


Districts as building blocks of sustainable cities

The translation and integration of all urban system solutions into large-scale deployment would be more challenging to achieve, as it involves various systems of energy, waste, mobility, and green and blue spaces, whilst cutting across development boundaries.

Many innovations in the urban environment have been introduced at the building scale, such as Singapore’s Building and Construction Authority (BCA) Green Mark Scheme to promote the construction of environmentally friendly buildings and Urban Redevelopment Authority’s (URA) Landscaping for Urban Spaces and High-Rises (LUSH) programme to encourage pervasive and accessible greenery in the high-rise urban environment.

The innovations at the building scale have certainly led the way in resource efficiency. However, the building scale may be too limited to include all aspects of urban systems at work, and sometimes neglect the spaces in between. The city scale, on the other hand, is more complex. To introduce new technologies and innovations at the city scale would involve huge sunk costs in built infrastructure, as well as greater legislative obstacles.

The district scale, as an intermediate level, provides greater flexibility and opportunities to promote the circularity of resources, economies of scale and testbeds for urban innovations without being too large and complex to manage. If proven feasible, it can be further scaled up.


Sustainability innovations at the district scale

The idea of prototyping district-level sustainability solutions is not new to Singapore. Following the introduction of the Green Mark scheme by BCA in 2005, the Green Mark scheme for Districts (GMD) was launched in 2009 and revised in 2013. The scheme recognises environmentally friendly and sustainable practices in master planning, design and implementation at districts of at least 20 hectares. While adapting energy, water and waste benchmarks to the district scale, criteria such as green transportation and stakeholder and community engagement are new inclusions at this scale. Recipients include CleanTech Park which garnered the Platinum Award and NUS University Town which obtained the GoldPlus award.

Singapore’s Housing and Development Board (HDB) is a major developer of public housing and towns in Singapore. It launched a district-level programme to create green and sustainable lifestyles through comprehensive and integrated framework of goals and strategies. New infrastructure such as a pneumatic waste conveyance system, solar panels and sensor-controlled lighting were also introduced. These HDB Greenprint initiatives have been piloted in Yuhua estate in 2012 and Teck Ghee estate in 2015. The pilot projects enable close monitoring and adjustments before such initiatives are implemented at a wider scale.

Singapore’s development expertise is also featured abroad, in collaborative projects like the Sino-Singapore Tianjin Eco-City. The project is a government-to-government collaboration between Singapore and the People’s Republic of China, spanning some 30 square kilometres. As of January 2020, the Eco-City houses a population of more than 100,000 people alongside 8,885 companies.

The Eco-City was designated as a National Green Development Demonstration Zone in 2014 which includes the “Eco-cell” system that encourages walking, through the distribution and accessibility of amenities for all residents. Furthermore, the Eco-City emphasises the conservation of the natural landscape as well as creating a strong industry and workforce. The Eco-City was also chosen as a testbed for sustainable solutions such as on-site plastics recycling and organic waste recycling in 2019. If such pilots are successful, they will be replicated to other Chinese cities and Singapore as well.

Sino-Singapore Tianjin Eco-City in China emphasises the conservation of the natural landscape (Image credit: Sino-Singapore Tianjin Eco-City Investment and Development Co., Ltd.)

Characteristics of a sustainable district

A sustainable district does not merely entail the piloting of discrete solutions. It must aim to expedite progress in our Global Goals, which remains laggard today despite the focus on cities as key levers. Doing so requires the integration of utility systems and elimination of any existing silos. This not only allows for exponential – rather than incremental – sustainability outcomes, but also a more liveable environment as compared to most other places. The following elaborates further on key features observed in sustainable districts around the world:

  1. Clear and ambitious sustainability targets. While definitions vary, a commonality in definitions of sustainable districts today is that they set clear and ambitious targets to reduce emissions and consumption of resources such as energy and water.

    Hammarby-Sjostad, an inner city district in Stockholm, Sweden, was a run-down and polluted industrial area in the 1990s before construction began to transform it. Today, it is a thriving residential district home to some 25,000 residents, and a poster child for urban renewal and sustainable districts. Ambitious environmental goals – such as using waste to produce district heating, and turning food waste into biogas for cooking and fuel – were integrated into the planning process from the outset. This allowed municipal authorities, urban planners, developers and architects to design sustainable alternatives for managing water, energy and waste in the district

    Another Swedish eco-district, the Stockholm Royal Seaport (SRS) district, has also set ambitious targets, including to be fossil fuel-free by 2030, and to reduce CO2 emissions from 4.5t in 2008 to a level below 1.5t per inhabitant by 2020.

  2. Integrated utilities. Developers within such districts must work across boundaries to optimise district infrastructure for resource sharing and connectivity. This is done through integrating utilities and modular systems beyond the building-level. The same principles of collaborating on and scaling up urban innovations can also be applied to brownfield sites and are not limited to greenfield developments only.

  3. Data-driven. Digital technologies are also layered onto integrated utilities for real-time data monitoring and additional efficiencies. Sustainable districts use data-driven smart solutions to monitor and manage energy and water use, and reduce carbon emissions. They typically have a strong IoT infrastructure in place, and use digitalisation to make it easier for residents and businesses to monitor their consumption patterns and be more environmentally friendly (see box story on Tengah Town).

    In the Swedish SRS eco-district, smart solutions include waste bins powered by solar which automatically compact the trash when needed and notify when they need emptying. Street lightings are self-controlled LED lights with preset lighting schedules, and pedestrian and bicycle paths are automatically lit when movement is detected by sensors.

  4. High liveability. Through better urban planning, sustainable districts tend to be highly attractive and liveable spaces which promote active mobility and wellness. For example, public transportation systems are designed to discourage the use of cars, hence reducing road traffic and congestions. Sustainable districts also often feature an integration of green, blue and grey infrastructure, with ample areas for recreation.
Punggol Northshore artists’ impression, showing the implementation of a biophilic design where green cover is integrated into recreational spaces (Image credit: Housing Development Board)

Punggol is Singapore’s first Eco-Town, featuring key developments such as MyWaterway@Punggol that incorporate mangrove plants and man-made floating wetlands. These not only provide green cover to the environment but improve water quality and create spaces for recreation. New precinct-level developments such as the Punggol Northshore district will also be planned according to a biophilic framework with key plant species introduced into the urban environment to promote and maintain biodiversity.

Box Story: Sustainable Marina Bay

Some other examples of Singapore’s investments in sustainable districts can be found in the Marina Bay area. New buildings constructed in this area must achieve a Green Mark Platinum rating at the minimum, creating a strong incentive for developers to pursue environmentally friendly and sustainable solutions. Marina Bay district houses the world’s largest underground district cooling system, serving 23 buildings (roughly 1.25 million sqm of gross floor area) including the Marina Bay Sands integrated resort. Customers using district cooling not only enjoy energy savings of more than 40%, but also save on space and upfront costs for on-site chillers. This frees up some 30,000 square meters of rooftop spaces for other uses like the infinity pool and restaurants at the top of Marina Bay Sands.

SP Group district cooling system at Marina Bay (Image credit: SP Group)

The nearby Gardens by the Bay has also invested in innovations in sustainability. In a pilot project with SP Group (SP), horticultural waste is fed to an on-site gasification plant which generates hot water for commercial usage. Waste volume is reduced by 95% through this process, minimising the need to transport the waste elsewhere to be incinerated, and the remaining solid charred waste from the gasification process can be reused in the Gardens. Other innovations present on the site included photovoltaic cells that have been installed to provide clean energy for light shows that take place at night.

Such investments embody district-level initiatives at promoting sustainability in energy, waste and the built environment. Singapore’s work in planning the Marina Bay area shows that sustainable districts are a promising development pathway to create liveable and sustainable urban environments without neglecting economic growth. Setting ambitious targets for sustainability goals through programmes such as the Green Mark for Districts scheme helps to promote district-level sustainability.


Opportunities for businesses

Sustainable districts allow businesses to pilot new revenue models. Given the need for integrated utilities at scale, private developers can own and manage entire districts before selling them at a premium later, rather than sell individual properties as quickly as possible – often before they are completed. Companies looking to testbed technologies may also explore offering ‘energy-as-a-service’. Customers need not make any upfront capital investment for the integrated utilities; they only need to pay a subscription fee for the service. New revenue models can thus help increase public buy-in and scale district-level solutions.

Beyond dollars and cents, sustainable districts also allow businesses to showcase new collaboration models. Co-creation between the public, private and people sectors is key to achieving ambitious sustainability targets and integrating utilities at scale. Given the transition away from building infrastructure in silos, a more collaborative business approach is required as well.


New revenue models

Box Story: SP’s Sustainable Energy Solutions for Tengah

SP’s work in Tengah, Singapore’s 24th HDB town, offers a glimpse of some innovations that have been introduced at the district scale. As the first “smart and sustainable town” in Singapore, it will be home to about 120,000 residents when completed.

Three of five residential districts in Tengah will be equipped with a centralised cooling system in a pilot project to adapt and deploy district cooling for residential use. SP Group is currently working with HDB to install the cooling systems on the rooftops of flats, where they are expected to accrue 25-30% of cost savings in comparison to traditional systems throughout their life cycle. In terms of energy consumption, the centralised cooling system is expected to provide up to 40% energy savings as compared to traditional air conditioning systems.

The introduction of the centralised cooling system gives SP Group further opportunities to introduce and integrate other energy-related eco-innovations and technologies into the built environment. Numerous initiatives are being planned, including the deployment of photovoltaic installations in the estate, gasification systems to allow for decentralised waste-to-energy recovery, charging systems for electric vehicles coupled with battery storage systems and sustainability-focused digital applications.

Digital Eco Boards will also be put up around the estate, reflecting energy usage and sustainability tips to residents on a regular basis. Two digital applications – MyTengah and OneTengah – will allow residents and municipal operators respectively to monitor energy consumption and make changes in their own capacity to improve energy efficiency and enjoy cost savings. 


Low-energy digital boards use smart meters to provide block-level information on water and energy use. (Image credit: SP Group)

In engaging future residents of Tengah Town with regards to the centralised cooling system, SP Group is piloting “energy as a service”. Under this model, consumers pay for cooling as a whole service, including recurring costs for chilled water depending on their usage, and periodic maintenance of the system. This allows service providers to tap on economies of scale. There are also consumer benefits – in addition to cost savings, residents who agree to the installation of the system ahead of time can have it installed in their homes by the time they move in.

SP Group engaged extensively with new residents to explain the life-cycle benefits of such a system. Many residents were supportive and signed up because of the long-term savings, energy efficiency and more sustainable carbon footprint. Successful implementation in the long run would not only mean a proof-of-concept for technological innovations like the centralised cooling system, but would also bode well for further exploration of new business models for providing services.


New business collaborations

By layering digital technologies over a district, there are opportunities to democratise real-time data and foster newer business collaborations. The Punggol Digital District, a part of Punggol Town, offers another approach for district-level innovation. It allows the public access to district-wide information collected by a network of sensors. The common platform allows interoperability between different users, which in turn enable businesses to tap on data and information provided by others in a “plug-and-play” fashion. Businesses can then contribute to the wider Punggol Digital District community by sharing their findings and co-creating new solutions.

The Open Digital Platform allows tech companies and start-ups to tap on live data to develop new solutions that optimise energy usage (Image credit: JTC Corporation)

The way forward

The urban innovations in Tengah New Town and the Punggol Digital District demonstrate that there are many approaches to creating sustainable districts. The scale of districts make them ideal testbeds for urban innovations. As a result, innovators from both public and private sectors have been able to prototype, test and scale-up their solutions.

These developments in turn help to grow the urban systems solutions industry. Enabling innovation platforms to test and scale-up solutions domestically would help Singapore create a core of urban systems solutions companies with a proven portfolio of projects. They can then export their knowledge to the region and the world, complementing government-level knowledge transfers in projects such as the Sino-Singapore Tianjin Eco-City.

To move the needle on sustainable districts, more needs to be done. This includes:


Mainstreaming public-private partnerships

Existing sustainable districts have shown the importance of private-public partnerships (PPPs). Government support is key in shaping policies and regulations that offer greater flexibility for the piloting of new technologies. Governments can create more favourable regulatory environments for new testbeds involving the private sector, such as through economic incentives. Businesses should also rethink their revenue models to capitalise on potential economies of scale. Importantly, a concerted effort will be required to strengthen the buy-in of end users, including residents, towards a more sustainable urban environment.


Studying the investment opportunities

The economic viability of sustainable districts in Singapore and overseas remains understudied, and warrants research into the opportunities and benefits for residents, governments and businesses. For example, the implementation of centralised cooling offers cost savings to users, lower energy demand from the national grid, and new business opportunities for service providers.


Developing a global benchmark

With good urban governance, sustainable districts are powerful prototypes that can lead to greater sustainability at the national scale. An important area for further development is in the creation of a framework as well as harnessing modelling tools for measuring the performance of sustainable districts. Comparing performance across sustainable districts allows for the sharing of best practices, improving performance across the board. 

Given the ‘re-scaling’ from city to district scale, existing standards and rankings need to be reconsidered. A global benchmark should be developed to evaluate the performance of sustainable districts worldwide. Importantly, this benchmark should consider the interconnectedness of urban modular systems and how synergies could reap multiplier effects in achieving the Global Goals – towards a more sustainable city and world.


This article was written in collaboration with the Centre for Liveable Cities (CLC) and based on the presentations and discussions at an Ecosperity Conversations webinar “Sustainable Districts for a Sustainable City” on 24 June 2020. An earlier version was published on the CLC website.

Laying the foundation for sustainable cities