While electric vehicles are green, some are greener than others. Electric cars differ because various manufacturers have their own idea about what consumers are looking for. With the imminent availability of plug-in hybrid vehicles, consumers will have more choices than ever.
Here is an explanation of the different electric powerplants and how they compare:
EV - Electric Vehicle or BEV - Battery Electric Vehicle
Nissan Leaf, Mitsubishi i MiEV
These are the "pure" electric cars. They have an electric motor only for propulsion. Typically they have larger batteries - up to 24 kWh - and have a range of up to 160 kilometres.
Pure electric cars typically don't have, or need, a conventional transmission. They just use a reduction gear. They also don't have a reverse gear - to back up the motor simply reverses the current to the reduction gear.
EREV - Extended Range Electric Vehicle
Chevrolet Volt
The Volt has a gasoline as well as an electric motor. Because of this, some people have mistakenly called the Volt a Plug-in Hybrid-Electric Vehicle (PHEV). The difference between an EREV and a PHEV is that a EREV's gasoline engine does not power the vehicle. When the battery drops below 20 per cent, the gasoline engine fires up to generate electricity to replenish the battery. The gas engine does not drive the wheels - it does in a PHEV. The Volt's electric-only claimed maximum range is 80 km. With its 35-litre gas tank, the Volt's range can be extended (that's why its called an EREV) up to 600 kilometres.
HEV - Hybrid Electric Vehicle - typically a gasoline-electric hybrid.
Toyota Prius, Honda Civic, etc. Gasoline-electric hybrid vehicles have been with us for a dozen years. A small battery, 1.3 kWh in the case of the Prius, augments an efficient gasoline engine. The two powerplants share propulsion duties, with the ability to run on pure electricity at low speeds for a limited distance. The electric motor also delivers additional horsepower when maximum power is called on - like passing on the highway - for brief periods. While the majority of models run on just their gasoline motor on the highway, some new models now boast of electric-only highway travel.
PHEV - Plug-in Hybrid Electric Vehicle
Upcoming Toyota PHEV Prius, Ford Fusion Energi, etc.
This is the newest category, with vehicles expected to be introduced within the year. These vehicles can be plugged in to be charged - just like an EV. The batteries are larger than a typical hybrid - 5.2 versus 1.3 kWh in the Prius - which allows them to operate solely on electric power until the battery is depleted. The car then reverts back to its gasoline engine, just like a hybrid.
PHEVs are eligible for a $2,500 incentive in B.C.
