From Extraction to End-uses and Waste Management: Modelling Economy-wide Material Cycles and Stock Dynamics Around the World

Abstract

Material stocks of infrastructure, buildings and machinery are the biophysical basis of production and consumption. They are a crucial lever for resource efficiency and a sustainable circular economy. While material stock research has proliferated over the last years, most studies investigated specific materials or end-uses, usually not embedded into an economy-wide perspective.

Herein, we present a novel version of the economy-wide, dynamic, inflow-driven model of Material Inputs, Stocks and Outputs (MISO2), and present a global, country-level application. Currently, MISO2 covers 14 supply chain processes from raw material extraction to processing, trade, recycling and waste management, as well as 13 end-uses of stocks. The derived database covers 23 raw materials and 20 stock-building materials, across 177 countries from 1900-2016.

We find that total material stocks amount to 1093 Gt in 2016, of which the majority are residential (290 Gt) and non-residential buildings (234 Gt), as well as civil engineering (243 Gt), and roads (313 Gt). The other nine end-uses covering stationary and mobile machinery, as well as short-lived products amount to 13 Gt. Material stocks per capita are highly unequally distributed around the world, with one order of magnitude difference between low- and high-income countries. Results agree well with similar global country-level studies. Low data quality for some domains, especially for lower income countries and for sand and gravel aggregates, warrant further attention. In conclusion, the MISO2 model and the derived database provide stock-flow consistent perspectives of the socio-economic metabolism around the world, enabling multiple novel and policy relevant research opportunities.

Keywords: social metabolism; dynamic MFA; economy-wide material flow accounting (ew-MFA); material efficiency; manufactured capital;