In a context of political commitment targeting net zero in 2050, controlling carbon flows is an essential operational imperative. The LOCUS methodology (Low carbon urban strategy) makes it possible to establish an exhaustive vision of carbon flows at neighborhood scale and to develop a strategy marking out the achievement of net zero in 2050. This unique approach, developed within the framework of the “Maillages Fertiles” research project, provides planners with information on: the carbon intensity of the neighborhood, the points of vigilance to consider during its development and the measures to prioritize to achieve net zero. Its application to the Praille- Acacias-Vernets (PAV) sector allows us to illustrate the structure of the method and to present the preliminary results obtained on this vast changing urban area.