Often I hear conversations between EV customers. They love evaluating and comparing their cars, but it is very difficult to make apple-to-apple comparisons without understanding the different technologies and thus advantages/disadvantages. For example, some EVs carry multiple engines and thus weight more than regular cars.
Electric vehicle or EV is the segment name. All EVs have e-motors that can be used independently to drive cars (without combustion engine support). The main difference thus becomes how long the installed batteries alone are able to power the car. The segment typically includes four types of cars: HEV, PHEV, REEV and BEV.
HEVs (like the original Prius) are typically the simplest form of EV. These cars cannot be plugged-in for charging but rather generate energy through the ICE or regenerative breaking systems. HEVs rely on the installed combustion engine and support it with a small e-motor.
PHEVs (like the Chevy Volt) can be plugged-in and thus have significantly larger batteries installed than HEVs. These cars can typically run for a two-digit number of miles on electric energy only which is either generated through the ICE or plug. The ICE supports the e-motor when more power is needed or the battery runs low.
REEVs (like the BMW i3 with REX) have a small combustion engine that is only used for charging the battery. The engine is disconnected from the drive train and can not run the vehicle without the e-motor. Typically these cars have a very small gas tank as customer rely on their battery range and rarely make use of the range extending combustion engine.
BEVs (like the Tesla ModelS) are pure EVs. These vehicles do not carry the extra weight of an combustion engine. Still these cars deal with weight issues as large batteries are installed to provide customers with long ranges. BEVs need to be plugged in for charging.
While all EVs will provide drivers with improved fuel economy, performance increases as the combustion engine gets smaller and the e-motor takes over. Because of the instant torque that e-motors provide, BEVs are among the fastest accelerating vehicles on the street. Finally, as BEVs do not rely on fossil fuels (at least after production and delivery) they can be 100% green, as long as it is charged with renewable energy.
Sini Ninkovic analyzes the EV market and its customers since 2012. He helped bringing BMW's i3 and i8 to market and currently works as Product Planner for Lucid Motors.