Everything You Need to Know About Regenerative Braking
One of the key selling factors for modern cars is being eco-friendly and technologically advanced. In order to pursue those goals and to minimize CO2 emissions and extend the electric drive range, engineers had to think of every possible way of generating energy. This includes leaving no potential energy sources to go to waste. Regenerative braking is one of those technologies that is based on an old principle, yet it makes so much sense today. Here is what regenerative braking is, and why it is here to stay.
What is Regenerative Braking?
Regenerative braking is a technology that converts the kinetic energy of a decelerating vehicle into electric energy that can be saved and fed back into the drive. Most electric vehicles and vehicles with hybrid drives use regenerative braking to charge the vehicle’s battery, which is why this energy recovery technology will continue to gain in importance over the next few years. This principle is fairly similar to the one you see on a rotating bicycle dynamo.
How Does Regenerative Braking Work?
The principle is fairly simple and it only requires a basic understanding of physics. To move a vehicle, a certain amount of energy is required. Once you burn fuel or use electricity to move, the energy required to do that is not lost. It is stored in the form of movement or kinetic energy. Physics teaches us that no energy can be destroyed, it may only be converted. It is our job to not let that energy be converted into waste. This is where regenerative braking comes into play. Instead of converting the kinetic energy into useless heat (thermal energy), the regenerative braking technology turns it into electric energy. When braking, the electric engine inside a hybrid or an electric car acts as a generator. While decelerating, the wheels transfer the kinetic energy to the generator through the drivetrain. The generator then acts like a bicycle dynamo and by turning, it transforms a part of that kinetic energy into electricity that is easily stored in the high-voltage battery. That is it!
Benefits of Regenerative Braking
The fact that a form of regenerative braking has been a part of Formula 1 since 2009, shows that there are significant benefits to this technology. Here is why this technology is going to be present in the future:
Increased electric driving range
Car manufacturers all strive towards increasing the electric driving range of their electric and hybrid vehicles. According to research, regenerative braking can’t extend the driving range by 10% or more!
Reduced fuel consumption and CO2 emissions
Introducing regenerative braking to hybrid vehicles resulted in significantly lower fuel consumption and CO2 emissions. This works particularly well in urban traffic due to the amount of frequent braking and acceleration.
Reduced use of mechanical braking
Regenerative braking deceleration is usually not powerful enough to stop a car in its tracks, but in the majority of cases, regenerative braking is enough to slow down in regular traffic. This reduces the wear of your regular brakes and helps with excessive brake dust pollution.
Why is Regenerative Braking better than “regular” braking
Like we mentioned before, the benefit of regenerative braking is capturing the energy of “movement”. With regular (mechanic) braking, the pressure you apply on the brake pedal will determine the amount of force that the brake pads project onto the brake discs. As a result, the car decelerates, brake discs heat-up under pressure and the movement comes to a slow halt. The kinetic energy of the movement was converted into thermal energy which disappears into thin air once the brake discs cool off.
With regenerative braking, we capture that energy and we store it back in the battery of the car so we can cover more miles. What really makes the difference is the fact that this process occurs even when driving downhill. As the car decelerates to maintain the same speed downhill, the electric motor automatically generates electricity and stores it as we go. The use of regenerative braking also lowers the amount of “torture” on your mechanical brakes which lowers the cost of car maintenance. Genius!
How Does Regenerative Braking Feel?
One common question regarding regenerative braking is how regenerative braking feels. To put it simply, it just feels like free coasting in neutral. In most cases, you won’t even know it’s happening.
Most modern electric cars like Tesla or the Jaguar I-Pace do offer different levels of regenerative braking. A high or strong level of regenerative braking simply means the car will come to an almost complete stop much quicker once you take your foot off the gas pedal. Some electric cars like the Nissan Leaf with the E-pedal even claim to be capable of one-pedal driving. This means that the regenerative braking system is capable of stopping the car on its own, without mechanical braking.
Future of Regenerative Braking
Based on what we are seeing in the latest electric car models, regenerative braking is not going anywhere. It is only getting better and more efficient with every new generation of hybrid and electric vehicles. Perhaps the biggest step forward in this field is Audi E-Tron’s “brake-by-wire” system. This system adapts the amount of regenerative braking by measuring the amount of pressure the driver applies onto the brake pedal. Depending on the amount of pressure, the car’s computer decides whether it needs to engage the mechanical braking system or not. There are still mechanical brakes present in case the regenerative braking isn’t capable of stopping the car or if the system fails.
Regenerative braking is in our opinion, one of the greatest features of any electric or hybrid car. The fact that we manage to capture the kinetic energy of movement and convert it back into electric energy by employing the motor as a generator is simply amazing. And judging by the rapid progress in recent years, we can’t be excited enough to see how far this technology will go.