Future Environmental Impacts of Metals: Findings from Integrated Scenario Assessment with Prospective LCA

Abstract

Metal production is not only energy-intensive and a major source of greenhouse gas (GHG) emissions, but is also associated with other impacts affecting human health and ecosystems. In the future, metal supply and its environmental impacts are likely to change, e.g., due to potentially declining mined ore grades or decarbonization measures required to meet climate targets. This thesis aimed to assess the future environmental impacts of metal supply, focusing on the effects of future ore grades, decarbonization pathways of steel production, and developments in interrelated sectors, particularly electricity supply.

The results reveal that life cycle impacts on a per-kilogram basis are likely to decrease for most metals and impact categories. Key measures are a greener electricity supply, increased recycling shares, and shifting to novel, electrified production technologies, provided that decarbonized electricity is used. The effects of declining mined ore grades may be compensated by such improvements. Nevertheless, emission reductions per kilogram of metal produced may be insufficient to fully compensate for the effect of growing global metal demand. Demand-related impacts are thus still likely to increase for many metals across several impact categories.

Further research is needed to cover additional metals and identify effective emission mitigation strategies, including demand-side solutions.