Transport fuel supply today, in particular to the road sector, is dominated by oil, which has proven reserves that are expected to last around 40 years. The combustion of mineral oil derived fuels gives rise to CO2 emissions and, despite the fact the fuel efficiency of new vehicles has been improving, so that these emit significantly less CO2 , total CO2 emissions from transport have increased by 24% from 1990 to 2008, representing 19.5% of total European Union (EU) greenhouse gas emissions.