Circular cities for sustainable growth

In the not-too-distant future, most of the Earth's population will live in large urban centres. The 3,500 million people currently living the cities will be 5 million by 2030, 70% of the entire population of the world.

Urban centres producing most of the polluting emissions and that is why they should be the starting point for solutions to combat climate change. To this we should add the current health emergency that will define our relationship with our surroundings.

In this context, the circular economy provides the vision needed to design the cities of the future. This transformation should enable the communities that inhabit them to not only be ready to face a health emergency but also to develop towards a sustainable economic model.

A metabolism that consumes resources and generates waste

The circular city is a development of the concept of smart city or intelligent city. It is all about a change in perception: From an outlook focussed on new technologies and energy services we move on to a holistic approach that takes into account all the resources consumed by a city and that puts the focus on the social, economic and environmental impact of that consumption.

Antonio Castellanos, of Circular Economy Iberia, compares cities with "a great metabolism that consumes resources, both energy and materials, and generates emissions and waste". The circular city is a development of this model to achieve sustainable development that includes environmental quality and sustainability, prosperity, economic competitiveness, equality and social inclusion.

Acting on the energy and materials that are consumed is key to a city's circular transformation. To do this, we need to move in several directions:

• Develop renewable energies so as not to generate emissions.
• Promote advanced models in collaborative economics to share resources and extend and optimise their useful life.
• Maintain and regenerate resources in use: Eco-design and manufacture of appliances that are easy to repair. Maintain the value of manufactured goods and products for as long as possible.
• Apply waste hierarchy and regenerate as much waste as possible.

As Castellanos explains, "In the circular economy theory, the waste produced is ZERO. Every product should be designed so that at the end of its useful life it does not generate waste or so that this the waste can be recycled. Even toxic waste. If this is not possible it means that the product has been poorly designed, that is, it has not been designed under the criteria of circularity."

This would be a graphical representation of a circular city: