Blended mode

Blended mode is a charge-depleting mode of operation for plug-in hybrid electric vehicles (PHEVs) in which most of the motive energy is supplied by the battery pack but supplemented by the internal combustion engine (ICE). In contrast, all-electric or battery electric vehicles use only the electricity provided by the battery pack as their sole source of energy in a charge-depleting manner. Both types of advanced technology vehicles use regenerative brakes to recapture kinetic energy that should not be considered a fuel source but rather an efficiency aspect of these types of electric vehicle powertrains not found in traditional internal combustion engine vehicles.

An example of plug-in hybrids that operate in blended mode while charge-depleting is the Toyota Prius Plug-in Hybrid. Because the Prius plug-in operates as a series-parallel hybrid, the U.S. EPA estimated its EV range for blended operation on a combination of electricity (from a fully charged battery pack) and gasoline as 11 mi (18 km) until the battery is depleted.

Blended mode uses both gasoline or diesel and electricity as sources of energy, and as such reduces the amount of liquid fuel used while displacing it with electricity. In such a mode of operation the fuel economy is increased, but the amount of electricity consumed, normally measured in kWh, must also be considered. In the United States such combination is measured through miles per gallon of gasoline equivalent.

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