Comparison of the Breakdown of Global CO2 Emissions and Cumulative Energy Demand Per Metal to Other Studies.

aIf not stated otherwise, the carbon dioxide (CO2) estimates include CO2 emissions from direct and indirect sources (i.e., upstream electricity production) [109]. Energy use is based on figures for final energy consumption [109], which refer to the energy supplied to the consumer, but do not include the transformation from primary energy carriers and feedstock energy.bDerived by multiplying the per kg global warming potential (GWP) and cumulative energy demand (CED) for each element with their global annual production in year 2008. See Table S38 in Supporting Information S1 for more details.cIEA (2008) [109] as reported in Allwood et al. (2009) [114]. Derived from Figure 16.6, page 483, in IEA (2008) [109].dBased on the average of the ecoinvent 2.2. unit processes “Steel converter, unalloyed, at plant/RER U” and “Steel converter, low alloyed, at plant/RER U”, multiplied with USGS global raw steel production figures for 2008 [53].eIEA (2007) [110] and IEA (2008) [109] as reported in Allwood et al. (2009) [114]. Assuming that aluminum accounts for 60% of CO2 emissions in the non-ferrous metals sector.fEmissions from cement production are not counted, which equal 83% of total energy use and 94% of CO2 emissions in the production of non-metallic minerals (Chapter 16, page 490 of IEA (2008) [109]).gBased on Figure 16.9, page 490, in IEA (2008) [109].hBased on Table 16.4, page 481, in IEA (2008) [109]. Only direct industrial energy and process CO2 emissions included.iOnly limestone production.jBased on Table 16.2, page 477, in IEA (2008) [109].kBased on page 194 in IEA (2010) [10].