Urban metabolism: a tool for analysis and action to stimulate territorial deployment of the circular economy

Philippe Genois-Lefrançois and Martial Vialleix, under the supervision of Professor Franck Scherrer and Professor Fanny Tremblay-Racicot, have carried out a literature review of urban metabolism and urban experimentation approaches to the territorial deployment of the circular economy. Discover the summary of their work. 

Summary

This research project is part of a global reflection on the identification and characterization of conceptual and methodological approaches likely to stimulate the urban deployment of the circular economy. With this in mind, it aimed to paint a picture of the ways in which the study of urban metabolism has been adopted within collective action approaches in urban planning and development. Urban metabolism is an interdisciplinary analytical framework studying the circulation and storage of resource flows (matter and energy) 1) within territories and 2) between territories and their hinterland. The research was mainly based on a systematic review of the scientific and grey literature, enabling a synthesis of existing knowledge on the possible implications of urban metabolism as a tool for analysis and action.  

The first phase involved cataloguing and classifying a wide range of publications and urban initiatives in Europe and North America. This database includes various characterization criteria: definition of urban metabolism; school of thought; scales and resources taken into account; normative dimension for collective action. 

A second stage of analysis produced a synthesis of existing knowledge on the links between urban metabolism and collective action in urban planning. Four cross-cutting findings emerged:  

1. There is a certain consensus on the essential role that the study of urban metabolism should play in the toolbox for deploying the circular economy on a city scale: whether this involves assessing the circularity of a territory or developing interventions there; 
2. The role of urban metabolism as a framework for collective action varies between heuristic and accounting vocations. The former corresponds to a reading of the territory based on the circulation of flows, while the latter concerns a set of quantification tools; 
3. Urban metabolism studies concern a restricted scientific circle, and are still struggling to scale up to include planning regimes. This is due in particular to a lack of tools for transferring knowledge to stakeholders, enabling them to integrate this framework into their practices, as well as to a range of socio-technical obstacles; 
4. Finally, a section of the literature highlights the potential of the field of urban planning to operationalize the concept of urban metabolism into tangible instruments and practices. In this respect, metabolic studies represent a new source of information for developing synergies between resource flows and urban components. 

Finally, a third stage involved studying specific cases of experimental planning and urban design projects incorporating urban metabolism. This phase generated a deeper understanding of the articulations of metabolic reading within existing planning approaches (contexts, specific stages and processes, urban objects, tools, heuristic perspective, accounting perspective). This has laid the foundations for the development of a typology of applications of urban metabolism for the urban deployment of the circular economy.  

Analysis of these examples seems to highlight the difficulty of overcoming the diagnostic nature of urban metabolism and integrating it as a tool for designing innovative urban planning strategies. In this respect, there is still a lack of data enabling us to understand the mechanisms and contexts conducive to 1) the appropriation of a metabolic reading within planning regimes 2) the role of urban metabolism in stimulating urban innovation. The research team also realized the lack of existing data to assess the concrete impact of using urban metabolism within urban-scale transition management processes (urban projects, scaling up of experiments, new collaborations, social learning, changes in practices, etc.). Complementary research avenues could include: 

• Deepen our understanding, through case studies, of the impact of urban metabolism approaches in urban transition processes towards the circular economy;  
• Deploy experiments with urban planning systems based on urban metabolism in Quebec, in order to gain a better understanding of how this theoretical perspective has been appropriated by the Quebec urban planning and development system.