All electric range (AER), is the range of a vehicle using only its electric fuel source or battery pack. In the case of a battery electric vehicle this would also be it's total range per charge. While in the case of a plug-in hybrid electric vehicle this would be the range of the vehicle in charge-depleting mode though it could have considerably more range in charge-sustaining mode while using some more traditional fuel. Although there is no technically mandated minimum all-electric range, future legislation may address this for policy purposes.
All-electric range is designated by the form PHEV-(number) representing the number of miles the vehicle can travel on electric power alone. For example, a PHEV-10 can travel ten miles without the use of petroleum gasoline.