During 2010, transport sector accounted for 27% of global final energy use, produced 6.7 Gt-CO2 direct emissions and represented 14% of GHG (global greenhouse gas) emissions, 7.0 Gt-CO2-eq [1]; with road transport dominating overall transport sector CO2 emissions [2]. Vehicle ownership (i.e. number of vehicles per inhabitant of a region) for road vehicles is high in developed countries, and tends to increase in the medium term in developing countries [3]. For instance, 2010 values for four-wheeler ownership were 657 vehicles/thousand people in North America and 426 vehicles/thousand people in the OECD (Organisation for Economic Co-operation and Development) Pacific countries; compared to 140, 33 and 23 vehicles/thousand people in Latin America, Asia and Africa [4]