Environmental consequences of policies in construction sector: combining economic simulation with consequential LCA

Abstract

Consequential Life Cycle Assessment (CLCA) can be particularly relevant for studying the changes proposed by new policies since they may result in important displacements of environmental, social and economic impacts. For example, the financial aids for encouraging the use of new technologies may increase the demand for some materials of which production is constrained and the marginal suppliers may be more impacting than the average ones. The goal of this project was to propose a method for calculating the potential environmental burdens and benefits from new policies in the construction sector. Consequential Life Cycle Inventory must include all processes that are actually affected by the studied changes, considering the market effects. The economic models can be helpful on this matter. The proposed method couples a Stock-Flow Consistent (SFC) to the CLCA methodology to obtain the flows and stocks that are affected by the new policy. The model goes further in order to obtain the second-order effects, i.e., the monetary redistribution effects resulting from an economic perturbation. The main result is a novel method that couples an SFC model to CLCA. It is tested in a case study where the evolution of carbon tax in France (economic shock) leads to an increase in thermal retrofitting works in the French existing built stock. These results may help the construction sector to anticipate important rebound effects that are not usually included in the current studies used for decision and policy-making.