Can You Gain Battery Power Braking on a Hill?

Remember that time in the original Karate Kid movie when Daniel LaRusso’s mom roll-started her lime-green Chevelle station wagon?

You felt bad for this LA transplant kid and his poor single mom. They had a real jalopy.

But however frowned upon this practice might be in good neighborhoods, the mechanics of it are solid. Now, in the days of hybrids and electric vehicles, drawing power from mechanical processes isn’t just for poor people any more. There’s a new process – and instead of just sparking the ignition, it actually saves power!

Regenerative Braking – How Does it Work?

New electric vehicles and hybrids have something called regenerative braking.

With this type of system, the energy used in braking actually gets converted to power. It’s a real advance in saving greenhouse gas emissions. It’s also due to save drivers a lot of money.

How does it work? When the driver brakes, energy is transferred to the motor. The motor goes into backwards mode. As it runs backwards, it generates electricity.

The electricity goes to the batteries, and you’re off to the races. Check out this detailed guide from How Stuff Works.

Braking and Recharging

So with regenerative braking, braking the vehicle actually charges the battery.

Could you recharge the whole battery on a hill?

That’s the question that Engineering Explained wanted to solve using a Tesla model S 60 and some precise calculations.

Theoretically, you’d need a hill about 6.5 miles high. However, because of limitations with the battery system, engineers found you’d really need a hill about the size of Mount Everest.

That shows, in a very visual way, that none of us are going to be “filling up” by braking.

But while you may not be able to recharge your whole battery on one hill, you can get free energy from braking with an EV. This new braking system can and will give you a charge – automatically! There’s no sucking power from the grid.

Think about using tax incentives and other strategies to get behind the wheel of an electric car. Rather than buying according to miles per gallon, wouldn’t you like to get some of those miles for free?


By Justin Stoltzfus
Updated: February 1, 2017