What Is Regenerative Braking

October 31, 2012

With the introduction of hybrid vehicles a new technology has been introduced to the automotive world, regenerative braking. On hybrid cars, such as the regenerative braking Prius, this system goes to work each and every time you step on your vehicle’s brakes. Typically, on a normal car, when you brake the energy and heat dissipates and is wasted away, not so with a regenerative braking system

What Is a Regenerative Braking System?

At its core, regenerative braking uses a mechanism that allows the vehicle to slow down while converting the resulting kinetic energy that propels the vehicle forward and would normally be wasted, into a useful form of energy instead of it merely turning into heat and wafting away. This converted energy is then stored in a battery and reused in other systems within the vehicle. In this manner the vehicle’s battery is constantly being re-charged, thus allowing the driver to not have to worry about plugging a hybrid vehicle in to an outlet as often.

How Does It Work?

Still, this can be a confusing process that isn’t always easy to understand. The heat created by the friction of the tires slowing on the ground, which is still wasted, but the energy normally lost between the brake pads and rotors is what is saved. When the car slows this energy is transferred to the vehicles electric motor, in a reverse, forcing the motor to run backwards. When this electric motor is run in a backwards direction it actually serves as a generator, charging the car’s battery. In order to allow this system to work, hybrid and electric, cars also have a friction type of braking system to act as a fail safe, just in case the regenerative braking system doesn’t create enough energy to physically stop the vehicle.

An Energy Recovery System

This type of system is often referred too as an energy recovery system. This allows vehicles driven by hybrid, or pure electric, motors to reuse this stored energy to power the vehicle. Gas consumption is drastically reduced in this manner on hybrid engines, allowing for far superior gas mileage than one would expect in a pure gasoline engine. This type of energy recovery system was originally designed in the late 60’s and used on the AMC Amitron, a complete battery driven vehicle concept car.

Limitations of the Regenerative Braking System

Regenerative braking does have its limitations. Typically the system that allows this transfer of power is only available on the wheels that drive the vehicle, thus front wheels on a two wheel drive, front wheel driven vehicle. This means your vehicle is only generating power on these wheels. In addition, wear and tear is more substantial on these wheels and brake pads may wear down faster than on other wheels. Furthermore, friction is reduced at lower speeds, meaning that the regenerative breaking is greatly reduced at low speeds.