A decision-making methodology of decarbonization for a dwelling stock in France

Abstract

Decarbonization is a hot topic in the building sector. In response to the national ambition of carbon neutrality in 2050, a social housing company that manages about 100,000 housings in France, wants to know how to decarbonize its dwellings. This dwelling stock form a heterogeneous dynamic group with new constructions and demolitions every year. Carbon emission is mainly caused by fossil energy consumption in the building exploitation phase, especially in space heating and hot water. There are many instructions to reduce energy consumption in building exploitation phase, like the thermal insulation of building envelope, the update of equipment, the energy transition, and the sobriety of energy...But how to organize these methods to find out an optimum with the restrictions of resources? How to take the initiative in an ever-changing political and technical environment? Inspired by the discipline of “System Dynamics”, we propose a methodology to represent and simulate the intricate system of the dwelling stock, to have a better insight into how the outside impacts, like the changes in policy and technological innovation, influence the inside system of the dwelling stock, and how the inside elements interact. This methodology is composed of two aspects: The typologies of housing type and the simulation of the dwelling stock. The 100,000 housing has been classed several times independently, which is quite distinct from the traditional classification method. The simulation part is carried out in the software “Vensim” and is based on the calculation method 3CL DPE. For each scenario of outside political-technical environment, we test several options to propose a suitable integration of concrete methods to decarbonize the whole dwelling stock.