this implies that the level of tax for a litre of diesel should be higher than that for a litre of gasoline to reflect relative environmental costs diesel vehicles also tend to travel further per litre of fuel than gasoline vehicles as they are often more fuel efficient this means that social costs such as congestion noise accidents and infrastructure wear are also higher on a per litre basis for diesel than gasoline in the energy sector the international energy agency iea estimates that the sources of around of possible cumulative greenhouse gas ghg emissions to under an energy scenario consistent with international climate goals are already in place or under construction leaving little room for additional polluting facilities iea