Thesis supervisor(s)
: Taoufik Souami
Within the discourse surrounding the desire for energy transition, there is a growing promotion of energy circulation at the sub-urban level between various activities. Local, national, and transnational actors are proposing, for example, to recover so-called "waste" heat produced by multiple activities (industry, data centers, wastewater, etc.). At the same time, there is a push to share decentralized energy production between different functions (residential, tertiary, commercial, etc.) at scales ranging from the block to the neighborhood. In short, forms of connection between urban activities for the exchange of energy are being promoted, and examples of implementation are multiplying.
This thesis proposes to understand these connections as new forms of urban networks, which replace or overlap with a century-old model of large centralized networks based on technical and economic efficiency, territorial solidarity, and growth in consumption. It aims to understand how the emergence of these local flows is changing the co-construction of cities and energy networks.
To understand these transformations, the thesis combines the contributions of two sets of work. On the one hand, urban and socio-technical research on networks provides insight into the reconfiguration of these infrastructures. On the other hand, the field of industrial and territorial ecology analyzes the dynamics that lead to exchanges of material flows between human activities. The combination of their results thus makes it possible to understand the subject under consideration in its social, technical, and metabolic dimensions, i.e., from a sociomaterial perspective.
The analysis is based mainly on three case studies, which seek to understand their emergence, functioning, and evolution: the supply of Dunkirk's heating network by an industrial heat source, heat recovery from a data center to supply a neighborhood in Marne-la-Vallée, and the pooling of energy production in the La Confluence neighborhood in Lyon. More broadly, the study looks at concrete or proposed reconfigurations of the organization of the energy supply chain in cities.
The thesis presents three main findings. First, these networks are no longer motivated solely by the technical and economic efficiency of the grid-based approach to supplying the territory. The interests of the various actors involved all relate to the objective of optimizing the use of flows: we are thus moving from a search for technical and economic efficiency to one for metabolic efficiency. Second, the networks that emerge from these exchanges are unstable, particularly due to uncertainties about the short- and long-term evolution of available flows. As a result, they do not reproduce the solidarity effect enabled by the stability of large conventional networks. Finally, in the face of these instabilities, stakeholders are proposing changes aimed at reducing dependence on uncertain flows. These changes are characterized by network growth that no longer follows a universalization objective. On the contrary, a strong spatial selection of network expansion is carried out, based on the materiality of flows as perceived by the actors. Rather than generating new consumption in a supply-driven logic, the aim is to integrate new flows that are already present in the territory.
In short, the thesis shows a certain "metabolic shift" in the process of connecting the city through energy. While the expansion of infrastructure has long been at the center of network construction issues, the flows produced and consumed that already exist in the territory may now be the primary motivation for creating connections.
Defense on Wednesday, January 11, 2017 Thesis in Spatial Planning, Urban Planning
Doctoral school
: VTT – City, Transportation, and Territories
Composition of the jury
:
Sabine Barles, Professor, Paris 1 Panthéon-Sorbonne University (rapporteur)
Nicolas Buclet, Professor, University of Grenoble Alpes (examiner)
Olivier Coutard, Director of Research, CNRS, UMR LATTS (examiner)
Gilles Debizet, Senior Lecturer, University of Grenoble Alpes (examiner)
Gabriel Dupuy, Professor, University of Paris 1 Panthéon-Sorbonne (rapporteur)
Laurence Rocher, Associate Professor, University of Grenoble Alpes (examiner)
Taoufik Souami, Professor, University of Paris Est (thesis supervisor)