 The Society of Automotive Engineers ' ( SAE ) definition of a hybrid vehicle states that the vehicle shall have " two or more energy storage systems both of which must provide propulsion power , either together or independently . " General Motors has avoided the use of the term " hybrid " when describing its Voltec designs , even after the carmaker revealed that in some cases the combustion engine provided some assist at high speeds or to improve performance . Instead General Motors describes the Volt as an electric vehicle equipped with a " range extending " gasoline powered internal combustion engine ( ICE ) as a genset and therefore dubbed the Volt an " Extended Range Electric Vehicle " or E @-@ REV . In a January 2011 interview , the Chevy Volt 's Global Chief Engineer , Pamela Fletcher , referred to the Volt as " an electric car with extended range . " 
