Electric vehicle technology has advanced rapidly since its introduction, and today there are many plug-in hybrid and battery electric vehicle options available on the market. But how, exactly, do electric vehicles work and what are their advantages?
Let’s start by considering the legacy vehicle technology: the internal combustion engine, or ICE. This vehicle is propelled by a combustion engine that can only be fueled by gasoline. The technology is conventional, well-established, and reliable, but it consumes large amounts of gasoline—which can be costly in many ways.
Enter the electric vehicle drivetrain! Unlike internal combustion technology—which uses combustion and pressure to propel a vehicle—electric vehicles, or EVs, are propelled by electromagnetism. These vehicles use electricity, typically stored in a battery, to power an electric motor. EV technology is used in hybrid electric vehicles, or HEVs; plug-in hybrid electric vehicles, or PHEVs; and battery electric vehicles, or BEVs.
Because each vehicle type incorporates different technologies, the range these vehicles can travel differs as well. ICE vehicles—fueled only on gasoline—typically can travel 350 to 450 miles on a full tank of gas.
Hybrid electric vehicles are more efficient in their use of gasoline and typically can travel 550 to 700 miles. Although they do have a battery and electric motor, this battery is only fueled during a typical drive cycle and is not a primary source of propulsion. However, due to regenerative braking, this small battery is the primary reason for the hybrid’s increased fuel efficiency and range.
The larger battery in a plug-in hybrid electric vehicle enables the vehicle to operate in all-electric mode, typically traveling 20 to 40 miles just on electricity. PHEVs are designed to support average daily commutes and easy overnight recharging using a standard outlet. After most of the energy in the battery is depleted, the vehicle can operate in hybrid mode for longer distances, running off gasoline and using a small portion of the battery to support the electric drivetrain, for a full vehicle range of 450 to 550 miles.
All plug-in electric vehicles, including plug-in hybrids and battery electric vehicles, use electric vehicle supply equipment, or EVSE, to charge their batteries.
There are three common types of EVSE. The first is referred to as a Level 1 charger. Typically, these units are portable cordsets that run off a standard 120-volt household outlet, and provide approximately 2 to 5 miles of range per hour of charging. This is the most affordable type of charger, but it is limited in the daily range it can supply to a vehicle. Therefore, this application is most common for PHEVs with smaller batteries, or for BEV drivers with a short daily commute to work.
The vehicles themselves also often display energy consumption or vehicle efficiency on their physical dashboard. Some vehicle models show lifetime energy consumption, so federal fleet managers will need to check the kilowatt-hours consumed annually to complete their FAST reports. However, if the vehicle displays the lifetime efficiency in miles per kilowatt-hour, fleet managers will need to divide the annual vehicle miles traveled by the vehicle efficiency to determine annual energy consumed.