Greenhouse gas (GHG) accounting methods for steel and aluminum products have begun converging towards common standards within their respective industries in recent years. However, accounting methods for steel products and aluminum products are still not fully comparable with each other. If emissions are measured and allocated differently for these products, then these accounting differences have the potential to influence materials choices for manufacturers concerned about reducing their reported GHG footprint. Companies could therefore be motivated to make a choice between aluminum and steel according to emissions benefits that materialize from differences in accounting frameworks, but which do not actually exist in practice. These incentives will materialize for any substitutable materials which do not use fully comparable GHG accounting frameworks. Bringing product-level accounting methods for substitutable materials such as steel and aluminum into alignment with each other is therefore necessary to eliminate this gap.
This study analyzes the major high-level differences between the International Aluminium Institute’s product-level guidance and cradle-to-gate product-level accounting in the steel industry, represented by a synthesis between the ResponsibleSteel International Standard and the Worldsteel Life Cycle Inventory Methodology.
John Biberman, Gyunbae Joe & Perrine Toledano,
Harmonizing Product-Level GHG Accounting for Steel and Aluminum,
Available at: https://scholarship.law.columbia.edu/sustainable_investment/16