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What A Plug-In Hybrid Does

It’s no secret plug-in hybrids are becoming more and more interesting to weary buyers anxiously seeing gasoline prices fluctuating. Plug-in hybrids, PHEV offer the best of both worlds but what exactly are they?


If hybrids are an almost common sight on our roads today, plug-in hybrids are barely hitting the market. A logical continuation of hybrids, a plug-in hybrid, as its names implies allows you to recharge the electric battery pack and drive on electricity only. But not all plug-in hybrids are made the same.

The EREV vs PHEV Debate. History will probably look back on the silly marketing stunt redefining a plug-in hybrid as an “extended range electric vehicle”, or in Fisker’s case, “Electric Vehicle Extended Range”, EVER and the copious amount of confusion it has created in the minds of potential buyers. But plug-in hybrid, the technical term designed to encompass two sources of energy using a rechargeable battery pack come in different drivetrains.

Series and Parallel Plug-In Hybrids. In the end, it all boils down to if the gasoline internal combustion engine drives the wheels or not. If a hybrid is defined as “a car with a gasoline engine and an electric motor, each of which can propel it”, according to the New Oxford American Dictionary, a plug-in hybrid can have the gasoline engine drive the wheels, or not. The difference becomes a series-plug-in hybrid, where only the electric motor propels the wheel, relegating the gasoline engine to the role of a generator hooked to an alternator, pumping electricity stored in a battery pack. A parallel plug-in hybrid will use both the gasoline engine and electric motors to propel the wheels. Series has the engine behind the battery pack and electric motor, parallel has both electric and gasoline work in parallel.

Best Of Both Worlds. If a series plug-in hybrid excels at low speed and cruising around town, it becomes much less efficient on highways. A parallel plug-in hybrid drivetrain becomes much more effective then. Hence, Mitsubishi’s soon-to-come out PHEV Outlander which will cover both of those deficiencies by becoming a series plug-in hybrid at low speed and switch to parallel plug-in hybrid at higher speeds. This Outlander will even give you the cherry on top of the cake by letting you chose between hybrid, gasoline and electricity only mode.

What About The Rest? Unfortunately, car manufacturers with decades of competition have brought the worse in marketing practices. The GM Volt, a great plug-in hybrid was hailed as a series plug-in hybrid, until GM decided it was to be more of an electric car than a hybrid. It then invented the electric vehicle with extended range misleading term only to admit less than a year after that the gasoline engine does drive the wheels, relegating it to a parallel and series plug-in hybrid, but certainly not the odd EREV marketing stunt the company is so eager to lobby governments into recognizing. The Fisker Karma is a true series plug-in hybrid, and makes even less sense as a range extended electric vehicle. Call a spade a spade and you will have a better-educated and informed buyer base that will not get confused.

As always, advertising practices don’t always give the best representation of what a company has to offer. They are meant to make you buy and buy. In the case of plug-in hybrids, what we need to remember is that different options exist and all serve their purpose well. A Series plug-in hybrid will excel in city driving whereas a parallel plug-in hybrid will be more efficient on highways.