MESSAGEix-Materials v1.1.0: representation of material flows and stocks in an integrated assessment model

Abstract

Extracting raw materials and processing them into products used in industry constitute a substantial source of CO2 emissions, which are currently lacking process detail in many integrated assessment models (IAMs). To broaden the space of climate change mitigation options to include material-oriented strategies such as the circular-economy and material efficiency measures in IAM scenario analysis, we develop the MESSAGEix-Materials module, representing material flows and stocks within the MESSAGEix-GLOBIOM IAM framework. We provide a fully open-source model that can assess different industry decarbonization options under various climate targets for the most energy- and emissions-intensive industries: aluminum, iron and steel, cement, and petrochemicals. We illustrate the model's operation with a baseline and mitigation 2-degrees (2 °C) scenario setup and validate base year results for 2020 against historical datasets. We also discuss the industry decarbonization pathways and material stocks of the electricity generation technologies resulting from the new model features. The next steps are to extend the model to other sectors, end uses and materials, as well as the combined modeling of various supply- and demand-side measures.