The world's population is increasingly urbanised, with over half of it living in urban areas. As the population of a city grows, the demand for electricity, transportation, heating and cooling increases, leading to high energy consumption and carbon emissions. This can exacerbate environmental challenges such as air pollution, climate change and water scarcity. The growing demand for energy and resources, coupled with increasing urbanisation, can lead to sprawling cities with rising physical and ecological footprints as well as loss of biodiversity.
Additionally, rapid urbanization can be a source of increased pressure on water resources, as cities compete with agricultural and industrial users for limited water supplies. Water shortages might occur, producing a significant impacts on human health and food security.
Reducing the ecological footprint of rapidly growing cities requires the cooperation of government officials, urban planners, industry and citizens, as well as comprehensive and integrated strategies for sustainable development. To reach this target we use a three dimensional approach based on sufficiency, efficiency and consistency.
The city-state of Singapore struggles with both localised flooding from intense rain showers and insufficient water resources. This requires the city to import water from neighbouring Malaysia. Through localised water management it is possible to address both these issues. Housing estates could be designed to collect and store rainwater to alleviate flooding issues, adopt nature-based solutions for filtering and cleaning water, and use collected water for domestic purposes, such as, watering plants, flushing toilets, washing and laundry. The grey water can be returned to the grid for centralised regeneration, reducing peak flows for both drinking water and waste water.
Singapore is also highly dependent on imports for food supplies. The government aims to have 30% of its nutritional needs produced locally by 2030, up from less than 10% in 2020. As Singapore does not have the space for large-scale area farming, the increase in food production will likely come from urban farming, with rooftops, blind facades and external corridors among the possible places for urban vegetable farming. Solar analysis can indicate which surfaces are usable and for what type of produce.
Finally there is a need for a holistic model of energy management at a neighbourhood, district and city scale. This includes local energy production through solar panels, local storage via battery stations and electric vehicle charging, district heat or cooling storage.
More details on our studies related to the resources supply and management in Singapore can be found here.
In order to reduce the ecological footprint, careful consideration of efficient use energy and resources has to be paid, in terms of sufficiency, efficiency and consistency. All three strategies towards sustainability are needed to reduce the ecological footprint of the cities and meet the net zero carbon strategy by 2050.
The idea behind sufficiency is to reduce the consumption of raw materials and energy as much as possible by reducing the demand for goods and services. Sufficiency is often associated with moderation and refers to modifications to lifestyles and business behaviour in order to limit the overuse of resources and energy.
Efficiency in urban systems can be achieved by maximizing the desired output of a process while minimizing its required inputs. For our cities this means reducing carbon emissions when heating and cooling our spaces and using less materials for the construction of our buildings.
The third pillar of sustainability is consistency and it refers to a reconciliation between nature and technology. In natural processes there is no waste, as everything is part of a cycle. In the built environment, we can adopt consistency from nature when considering buildings and the flows of energy they embody.
The adoption of sustainable building practices, including the transition to circular cities, can help rapidly growing urban areas reducing their ecological footprint. In a circular city, resources are used and reused in a closed-loop system to minimize waste, reduce environmental impact, and increase resilience and regeneration. This involves implementing practices such as designing buildings for disassembly and reuse, promoting repair and refurbishment of products, utilizing renewable energy sources, and fostering regenerative design principles.
Digitalization plays a key role in enabling circular cities, by facilitating the sharing of resources and information, optimizing resource use, and promoting transparency and accountability. Digital platforms can play a crucial role in facilitating the matching of supply and demand of resources by providing a centralized database that tracks their availability and connects suppliers with potential users. In this image you can see the in-house developed digital platform with insights on materials and components available in a city to enable matching of supply and demand .
Overall, a circular city is a more sustainable, resilient, regenerative, and liveable city, that meets the needs of both current and future generations.