Plug-In Hybrid Electric Vehicle (PHEV)
A PHEV is similar to an HEV except it is plugged into a charger to replenish its batteries. The charging port could be a 120- or 240-volt home unit or a public quick charger. A PHEV can operate for a short distance on electric power only. Typical range is 10-30 miles, depending on your driving style.
PHEVs often have multiple drive settings. The driver can choose to use only electric power, reserve battery power for later and burn gas instead, or use a combination. A survey by the Union of Concerned Scientists revealed that about half of Americans drive less than 40 miles a day. With charging facilities available where they work, study or shop and a PHEV with a 20-mile range, those drivers would burn almost no gas at all.
Actual mileage depends on the driver. Those who start and stop fast will use up the battery charge faster. When accelerating hard, some PHEVs will engage the gas engine to augment performance. So lead-foots may burn gasoline speeding away from the charging station.
Some plug-ins employ a range-extender engine that is never intended to power the wheels. It is designed only to charge the battery and will engage when the charge is low. This gives electric car cleanliness with gasoline range.
The Chevy Volt is a range-extended plug-in hybrid that uses a 1.4-liter 4-cylinder engine to charge a lithium-ion battery pack. The original version could travel 35 miles before using the range-extender or plugging in. The newest model, using a denser battery and lighter components, has a range of 50 miles.