First up on our new series, Ask the EV Expert, we field a question from Dave in Arkansas. Have a question of your own? Post it on Facebook, Tweet at us or email us at info@pluginamerica.org #AskTheEVExpert
I think I read somewhere we should ride our electric car’s brakes downhill to regenerate energy for the battery. Is that right?
Question:
I think I read somewhere we should ride our electric car’s brakes downhill to regenerate energy for the battery. Is that right?
Answer:
What you are describing is known as “Regenerative Braking” and is one of the coolest features of electric cars! Regenerative Braking, or “Regen” for short, allows electric cars to recapture energy that is wasted when braking. In a gas car, the act of braking is an attempt to absorb the energy of the car moving forward – in effect, stopping it. However, the energy absorbed by the brake pads isn’t re-used by the vehicle; instead, the energy is transformed into heat – that’s why the brakes get hot.
In an electric car, the inertial energy of the car moving forward can be re-used! When an electric car driver eases off the accelerator, the electric motor is instantly transformed into an electric generator. In effect, the wheels of the car are turning the motor, which is generating electricity that is then stored in the battery. This system is so efficient that most electric cars utilize this type of “motor braking” if you will, when the driver presses down on the brake pedal.
As a result, riding your brakes down a hill in an electric car doesn’t hurt the disc brakes like it would in a gas car because the electric car only uses the friction disc brakes when the driver needs to stop the car quickly or to hold the car at a complete stop, saving drivers lots of money in brake jobs!
Additionally, most electric cars are also equipped with a special “Regen” or “Low” mode that allows for a larger amount of energy to be reabsorbed back into the battery. Because there is more energy being absorbed, there is more braking force, and many electric car drivers can do what’s called “one pedal-driving” where they only need to press the accelerator to go faster, and rely on this “Regen” mode to sufficiently brake the car. So, yes, go ahead and ride those brakes down the hill and enjoy some free electrons!
