Life cycle assessment: a time-series analysis of copper

This paper presents a time-series Life Cycle Assessment (LCA) approach to examine the historical environmental impacts associated with copper mining and smelting in Australia from 1940 to 2008. It uses cradle-to-gate LCA models to estimate impacts from the five largest Australian copper mines, incorporating changes in ore grade and differences in technologies and regional energy sources. Using copper as an example of the different life-cycle impacts of metals, this study demonstrates the influence of both temporal and spatial factors. For mine/smelters, results show that the carbon footprint of copper produced at all sites over the time period investigated ranges from 2.5 to 8.5 kg CO2-eq./kg Cu and the difference between different locations in any given year can be up to 6 kg CO2-eq./kg Cu. The estimated impact potentials derived from the LCA models for Australiaʹs largest mine/smelter at Olympic Dam are then compared to impacts reported by mine operators for global warming potential and acidification. The results of the LCA analysis indicate the importance of considering time-varying parameters and highlight an opportunity to use LCA models more broadly for assessing future technology and energy options in the mineral sector.