Resource implications of alternative strategies for achieving zero greenhouse gas emissions from light-duty vehicles by 2060

This paper examines alternative strategies for eliminating the use of oil for passenger transportation in light duty vehicles (LDVs: cars, SUVs and light trucks) by 2060, namely, deep reductions in the energy intensity (MJ/vkm) of LDVs combined with a shift to hybrid and/or all-electric vehicles, or combined with a shift of the residual fuel requirements to C-free fuels (either renewable biofuels or hydrogen produced from C-free energy sources, and used in a fuel cell). Different combinations of these measures have dramatically different implications concerning land area requirements (for biofuels), additional electricity requirements (for electric vehicles or to produce hydrogen electrolytically), and in the demand for potentially limiting metals (Pt, Ru, Li and Nd in particular). Recent estimates of battery, fuel cell and motor sizes in advanced vehicles, and corresponding material loadings, are combined with scenarios for the growth of the global vehicle fleet and recycling potential to estimate future material requirements. For any of the alternative to fossil fuels to be sustainable over the next century, it is essential that LDV energy intensity be pushed to the lowest technically achievable potential, that significant reductions in precious metal loadings be achieved, and that 90% or better recycling efficiency be achieved. Even then, longer term sustainability is not guaranteed, which implies that the primary emphasis in urban development and redevelopment over the next century should be to create cities with little to no dependence on the private automobile for transportation.