How do climate and energy objectives influence the renewal of the role of network infrastructures in urban planning and the running of urban systems? The example of the revival of interest in district heating networks provides a few possible answers to this question, which is central to the understanding and characterization of the conditions for carrying out the urban energy transition. In this paper, we study this example by analyzing recent changes in French regulations and the process of creating an intercommunal energy-related competence in the Lyon metropolitan area. Emphasis is placed on the institutional and political conditions surrounding a change in governance as well as the underlying justifications in the reconsideration of an existing infrastructure in view of new energy, climate, and social challenges within a specific urban context. Our study has been carried out in reference to several discussions on urban planning and on institutional, political, and spatial factors that shape urban infrastructure regimes.