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How Regenerative Braking Works

Hybrid Regenerative Braking
Hybrid vehicles make use of an internal combustion engine and an electric motor.
Hybrid vehicles make use of an internal combustion engine and an electric motor.
©­­iStockphoto/­David H. Lewis


How is a hybrid vehicle different from a fully electric vehicle? Well, hybrid electric vehicles use both an electric motor and an internal combustion engine to provide a best-of-both-worlds driving experience. They combine the driving range of an internal combustion engine with the fuel efficiency and emissions-free characteristics of an electric motor. If a hybrid is to have maximum fuel efficiency and produce as few carbon emissions as possible, it's important that the battery remain charged as long as possible. If a hybrid vehicle battery were to lose its charge, the internal combustion engine would be entirely responsible for powering the vehicle. At that point, the vehicle is no longer acting as a hybrid but rather just another car burning fossil fuels.

Automotive engineers have come up with a number of tricks to wring the maximum efficiency out of hybrids, like aerodynamic streamlining of the bodies and use of lightweight materials, but arguably, one the most important is regenerative braking. In a hybrid setup, however, these types of brakes can provide power only to the electric motor part of the drivetrain via the vehicle's battery. The internal combustion

engine gains no advantage from these kinds of brakes.

In part, these efficiencies are necessary due to the extreme difficulty in finding a place to recharge a hybrid. This makes longer trips difficult without relying on the hybrid's internal combustion engine, which actually cancels out some of the advantage of owning a hybrid.

Up next, we'll learn about a new take on this idea of regenerative braking.