• The main petroleum liquids used in road transport are gasoline and diesel through internal combustion engines; gasoline is mainly used in passenger cars, light duty vehicles and passenger two wheelers whereas diesel is used in all forms of road transport, except passenger two wheelers.

• Today attention is increasingly turning toward PHEVs, which use both grid electricity and gasoline as fuels.

• In general, the more energy the battery is capable of delivering, the greater the gasoline fuel savings.