Rules for a Circular City

When is a city circular?

During Hacking the City event, organised in April 2021, we had the pleasure of having with us Professor Michela Passalacqua, Vice-Chancellor for Legal Affairs at the University of Pisa, who explained which rules to follow in order to create a circular city.

The professor began her speech by explaining that the city as we know it is actually opposed to circularity. Why?

In order to develop and exist, cities have to consume land, whereas the city becomes circular when it is able to contain this consumption. The issue of soil consumption is very important for sustainability, because soil, originally conceived as a hidden resource that we do not see and that is essential, renders services that are fundamental for our existence, namely ecosystem services. Therefore, the more we build up urban areas and productive activities in our cities, the more we consume its soil and we use up its ecosystem, the harder it will be to restore it. In fact, naturalisation processes never return soil to its original characteristics.

The European Union is very attentive to the issue of the circular economy, sustainability and reducing soil consumption, but despite this, it has not managed to adopt a directive on the latter. There has been a lot of discussion about this, but the project has stalled because of the economic interests behind the use of land, because both urban life, i.e. housing and production activities, need to consume soil in order to exist. Unfortunately, therefore, it has not been possible at European level to adopt a framework directive that all Member States must comply with.

Circular cities: regulation

In Italy, the regions are very active in making laws to promote soil and urban regeneration. Even since 2013, the national legislature has been dealing with this and a bill on the subject is being discussed in Parliament. The containment of land-use is no longer seen in a reductionist way, as a mere building factor, but it is associated to a change of paradigm in the economic development. For example, to reduce the built environment, the idea of reusing soil that has already been consumed, to move towards a circular economy, providing for reuses that do not reintroduce the dynamics of degradation that have already taken place on that soil.

This means to be somewhat of a futurist, that is, knowing how to design a reuse that can imitate nature and can guarantee a regeneration of those assets that have already been used.

The role of architects

Looking at the creators of the design model of productive processes that are capable of regeneration, reference is made to two 20th-century architects, testifying the fact that the theme of regeneration, reuse and therefore circularity and knowing how to regenerate property that has already been used, has its roots in urban science. The first is John Lyle, an American landscape architect who pioneered regenerative design in the 1970s aimed at the use of renewable local resources. The other, Walter Stahel, a Swiss architect who foresaw the transition to sustainable design by ceasing to focus on increasing demand for raw materials and the accumulation of waste. In other words the idea of designing land and territorial uses constantly aimed at not producing externalities.

Circular economy and real estate

In this circular economy perspective, how can we qualify real estate when it is already being used? It is often abandoned and where perhaps ecosystem services are no longer rendered as originally. If it is uncontaminated land, then it cannot be equated with waste because even if the owner decides not to use it any more, the non-exercise of the right of peaceful enjoyment does not determine the extinction of the right of ownership. When, therefore, can circular logic be applied to these uncontaminated funds? When they are considered not as a waste, but as a resource to be reused.

On the other hand, when we are dealing with contaminated land, which is often in our cities or in urbanised areas, even if European directives do not provide for it, it can, according to the professor, be conceptually likened to waste.

European directives do not equate contaminated land with waste because waste directives only deal with movable property. Immovable property, on the other hand, is very much linked to the issue of sovereignty. European law does not enter into the sovereign exercise of power by member states and does not want to dictate rules on these. From a conceptual point of view, however, since the EU obliges the reclamation of contaminated sites when a property is contaminated and is abandoned, then at that point the owner’s manifestation of his intention to dispose of that property emerges because he is obliged to carry out reclamation, which is very costly.

Contaminated soil and regeneration

Therefore, considering contaminated soil on the same footing as waste means rethinking contaminated soil from the point of view of regeneration and circularity, placing it within the circular economy, as regulated in some way by European law. At the moment, however, contaminated soil is not regulated by the second package of circular directives. But it can be said that it can become an elective sector for the circular economy, just like food and waste. Public intervention is essential for this to happen, she continued, and it is unthinkable to leave this kind of task entirely to the private sector.

Regenerating contaminated soil that does not equate to waste when it is in the city, and therefore in urbanised land, is in everyone’s interest. Why? Because if they are not regenerated, there is no attempt to reintroduce them into the circular process of imitating nature and bringing them back into use and reducing degradation, and they will certainly become factors of segregation, discrimination and environmental pollution.

Technological and social innovation

Soil regeneration therefore requires both technological innovation, because specific techniques are needed to regenerate it, and social innovation, because, as all regional laws and national regulations underline, regeneration requires the involvement of the community. In fact, all regional laws in Italy, concerning regeneration, foresee a preventive consultation of the community present in those soils and that can make a contribution to indicate what can be the circular and sustainable reuse of these soils. In this sense, regeneration could be assimilated to resilience, since it brings innovation and it is not about restoring what was, but it is about finding solutions in overcoming the negative elements of the use and finding a new use, an innovation that becomes greater knowledge of those places and re-integration in a process of value of those places.

Regeneration impact

By regeneration we mean a complex and coordinated set of building and urban planning interventions that have an effect on the urban quality that refers to the liveability of places by the residents, but also an effect on the economic and social system. In fact, regeneration is no longer confined to impacting on the social diversity or on the social degradation of a certain territory, but on the contrary there is the awareness that it is an integrated intervention, not only on building and urban planning, but also on the economic system, because only if there is no economic degradation it is possible to have a reuse that does not create new degradation also on the social system.

In particular, regeneration, regional laws and state bills on the subject, associate it with the containment of land use and the enhancement of the ecosystem performance of that territory in the form of reduction of water and energy consumption with a view to sustainability. From this point of view, too, the community re-emerges, just think of energy communities, of the idea of the consumer who, thanks to innovation, also becomes a producer of renewable energy, who in the city, the prosumer, consumes, produces and exchanges energy on an equal footing, perhaps with his neighbour, achieving urban regeneration that makes circularity its paradigm, without forgetting the issue of restoring ecosystem services.

Governance and public role

Governance of this innovation must not be left entirely to private industry, a risk that could be inherent in the circular economy, and which would mean a kind of privatisation of sustainability precisely because of the importance and sensitivity of the interests at stake. On the other hand, the role of the public player and public power is crucial.

Regional laws still say very little about ecosystem services, but the professor was very critical of the idea that we can solve the problem of using these services simply by monetising them. In many bills, an economic value was attributed to them, because soil, when in its natural, non-man-made state, filters and purifies water, replenishes water tables, stores greenhouse gases, reserves genetic resources, ensures biodiversity and so on. All these services that soil provides when it is consumed are compromised. An attempt is now being made in this bill to introduce the concept of balancing the budget for ecosystem services. A balanced budget should not depend so much on monetisation, i.e. the economic valuation of ecosystem services, but on their social valuation. The idea is therefore that every time land is consumed, ecosystem services must be balanced by restoring compromised ones elsewhere.


It is not considered an ideal tool, professor concluded, but it is important that our Parliament is finally addressing the issue of what lies beneath the built environment and how our development model, if it fails to preserve ecosystem services and understand the strong link between human life and the soil, is unlikely to be able to address the issue of sustainability and ensure a circular city.

If you want to know more check professor speech in italian below.

Do you want to find out more information on circular economy and its themes? Visit Tondo’s blog! And if you are interested into finding a community of companies and organizations that focus on circular economy and share experiences, knowledges and much more, join our communities of companies!

Francesco Castellano

Francesco Castellano holds a Master degree in Business Administration, and he has gathered almost twenty years of experience in research, finance, consulting, and business management. During this time, he was engaged in different types of projects as a consultant at Bain & Company, launched Uber operations in Turin, and worked in the FP&A department at General Electric.Lately, he founded To... Read more

Francesco Castellano holds a Master degree in Business Administration, and he has gathered almost twenty years of experience in research, finance, consulting, and business management. During this time, he was engaged in different types of projects as a consultant at Bain & Company, launched Uber operations in Turin, and worked in the FP&A department at General Electric.

Lately, he founded Tondo, a cluster of organizations focusing on spreading Circular Economy approaches and concepts, and supporting companies in the transition to a clean and circular future. Francesco is also the ideator and coordinator of the Re-think Circular Economy Forum, a format of events organized in many different locations in Italy showcasing the most relevant Circular Economy solutions.

Francesco has been a guest speaker at different universities and events, like Federico II University, Bocconi University, LIUC - Cattaneo University, Pavia University, Padua University, Catholic University, IPE Business School, 24ORE Business School, Campus Party, Torino Stratosferica, Visionary Days.

Francesco is passionate about Circular Economy, Cleantech Innovations, Venture Building and Entrepreneurship.