How Tesla's Regenerative Braking Works

By Kevin Armstrong
Tesla offers three stopping modes
Tesla offers three stopping modes
Not a Tesla App

Braking is essential to the driving experience, but not all systems are created equal. A regenerative braking system (RBS) is the most significant difference people notice the first time they operate an electric vehicle.

Regen, as commonly referred to, makes it possible to drive a Tesla and never touch the brake pedal (along with some brake blending for slow speeds), not only reducing wear and tear on braking components but putting energy back into the battery. There are some estimates that regenerative braking can add 10 percent more range and extend the life of braking mechanisms by more than 50 percent.

What is Tesla's Regenerative Braking?

Unlike traditional brakes, which rely on friction to stop the wheels from turning, regenerative braking uses the vehicle's electric motor to create resistance to slow down the vehicle. In addition to slowing the vehicle down without the use of brakes, the motor running in reverse acts as a generator and captures the kinetic energy that would typically be lost as heat and converts it into electrical energy, thereby increasing your vehicle's range.

How to Activate Regen in a Tesla

In a Tesla, the regenerative braking system is activated by lifting your foot off the accelerator. The more you ease off the accelerator, the stronger the braking force and the more energy is captured.

Tesla's Power Meter (Regen bar)

Tesla's power meter, also known as the regen bar or line
Tesla's power meter, also known as the regen bar or line
Not a Tesla App

All Teslas feature a power meter either in the instrument cluster (Model S and X) or the center screen (Model 3 and Y) that displays the amount of energy being captured through regenerative braking, or the amount of energy being used by accelerating the vehicle.

The center of the line is considered neutral. Anything to the left of the center point means energy is being captured, while anything to the right means that energy is being used.

The further the line grows to the left, the greater the amount of regenerative braking is taking place, and the more it moves to the right, the greater the amount of power is being used.

The regenerative braking line is green, while the power line is black (or white when in dark mode). You may occasionally also see a gray line on the left side. This will appear if the vehicle has the 'Apply Brakes When Regenerative Braking Is Limited' feature turned on. This feature introduces a consistent braking experience when lifting your foot off the accelerator pedal when regenerative braking is limited.

You may also see the gray line appear on the left side of the power meter if the vehicle is in Autopilot. This helps the driver understand when the vehicle is using regenerative braking or physical brakes to slow down.

How Does Regenerative Braking Work?

Without getting too deep into Physics, kinetic energy is energy in motion. Therefore, anytime a car slows down, the kinetic energy that is produced has to go somewhere. With traditional brakes, that is heat from abrasion generated from the brake pads squeezing the rotors. But this energy can be used in a different way. In the words of a Tesla engineer, "kinetic energy stored in a moving vehicle is related to the mass and speed of the vehicle by the equation E = ½mv²."

You can see this equation play out every time you drive your Tesla by looking at the vehicle's power meter.

The motor controller manages the torque of the motor. This action helps with both driving and regenerative braking. The position of the accelerator pedal tells the motor controller how much torque is needed. The motor controller then changes this into a voltage or current that produces the correct torque. The rotating force can be positive or negative. When it is negative, it means the vehicle is slowing down, and energy is returned to the battery.

Regenerative Braking Explained

Regenerative Braking Extends the Life of Your Brakes

One of the benefits of regenerative braking is that it can help to lengthen the life of your brakes. Regenerative braking slows the car reducing the work of your traditional braking system. In fact, Tesla estimates that their cars experience 50 percent less brake wear than conventional gasoline cars. Elon Musk predicted that Tesla's Semi would have brake pads that would "literally last forever" because the regenerative system would save those pieces from being used extensively.

It's estimated that regenerative braking captures up to 70 percent of the kinetic energy usually lost during braking and is put back into the battery. As described above, that energy can then extend the range between needing to charge.

Does Regenerative Braking Activate Your Brake Lights?

During regenerative braking, Tesla will still activate the brake lights when the vehicle is slowing down, even if the brakes aren't being used at all. Tesla determines whether to turn on your brake lights based on your vehicle's rate of deceleration. If you're unsure if your brake lights are on, look at your Tesla screen, the car in the display shows the brake lights lit up when the brake lights are activated.

Levels of Regenerative Braking

It's important to note that regenerative braking cannot be turned off. There are two regenerative braking modes for 2020 and older models — low and standard. Tesla recommends that you use standard to maximize your vehicle's range. At some point in 2020, that choice was taken away, presumably to use all the benefits of regenerative braking all the time. However, there were some concerns, as regenerative braking can slow down the car rapidly; therefore limiting traction, the vehicle could slide. Tesla has this warning on its website: In snowy or icy conditions, Model S may experience loss of traction during regenerative braking.

Tire Configuration

The company also notes that installing winter tires may temporarily reduce regen. But the vehicle's systems are constantly recalibrating, so the feel of the vehicle will return to what the driver is used to after a few miles or trips.

You can speed up the calibration process by selecting the type of tires your vehicle is using. To select the type of tires your vehicle is using navigate to Controls > Service > Wheel & Tire Configuration > Tires and choose the appropriate tire type.

Regenerative Braking Limited or Reduced

Regenerative braking is not available or can be limited during certain conditions. If this happens, you may see a dotted line in the vehicle's power meter. If the battery is fully charged, there is nowhere for the kinetic energy to go. Consequently, regen won't work. It also has limited usage during cold weather due to a cold battery. In these cases, you can choose to activate 'Apply Brakes When Regenerative Braking Is Limited' to provide a consistent slow down experience. Tesla stated, "Your car can now automatically apply regular brakes for consistent deceleration when regenerative braking is limited due to battery temperature or state of charge." But the company did leave this as a preference, and the option can be turned off. You can activate it under Controls > Pedals & Steering.

Stopping Modes

Regenerative braking works best at certain speeds, if you're traveling too slow, regenerative braking may be limited or not available at all.

In a Tesla, your vehicle will use regenerative braking whenever you lift your foot off the accelerator pedal. However, if you're using Tesla's 'Hold' stopping mode, which allows you to drive with a single pedal most of the time, the vehicle will automatically blend in the vehicle's brakes when traveling 4 MPH (6.5 KPH) or slower.

If you're using Tesla's 'Creep' or 'Roll' stopping modes, the vehicle will never apply the brakes when lifting your foot off the accelerate, which means the vehicle will continue to roll at slow speeds when regenerative braking is no longer effect.

A Brief History of Regenerative Braking

Tesla used regenerative braking in its first car — The Roadster, in 2008. A year later, the same mechanics of the system were implemented in Formula 1. It is called KERS, which stands for Kinetic Energy Recovery System. It provides such a horsepower boost that it was banned for a season before being regulated the following year. However, this advanced system dates back to the late 1800s.

The Sprague Electric Railway and Motor Company is the earliest known use of the technology in 1886. General Electric used regen in 1936 in its locomotives, and Oerlikon, a Swiss company utilized some components of the system in its gyrobus. The Amitron, a concept electric car created by the American Motor Car Company included regenerative braking in its designs. Toyota introduced the technology to its brand with the Prius Hybrid in 1997 and GM's EV1 had regen when the company sent the cars to the crusher.

Regenerative braking is now a staple of the electric vehicle experience, not only reducing maintenance costs but also improving the vehicle's range and letting drivers accelerate and slow down with a single pedal.

Elon to Switch to the Cybertruck; Volume Production in 2024

By Kevin Armstrong
Cybertruck mass production to start in 2024
Cybertruck mass production to start in 2024
Kim Java

Tesla's fourth quarter and 2022 earnings call with investors was mostly good news unless you were planning to drive a Cybertruck soon. While company executives eagerly jumped on every question asked by investors, there was a noticeable pause when a point-blank question was asked about Cybertruck's mid-year production date.

Elon Musk responded "um, we do expect production to start, I don't know, maybe sometime this summer. But I always like to try to downplay the start of production because the start of production is always very slow. It increases exponentially, but it's always very slow at first. So I wouldn't put too much thought in start of production."

Volume Production Next Year

If the millions of people with Cybertruck reservations were in attendance, you might have felt the air leave the room. The previous belief was mass production would start by the end of 2023. There may be some stainless-steel beauties on the road by then, but only a few. "It's kind of when does volume production actually happen, and that's next year," said Musk.

Perhaps sensing some disappointed buyers, Lars Moravy, Tesla's Vice President of Vehicle Engineering added, "(I'd) like just to emphasize on that, we've started installation of all the production equipment here in Giga Texas, castings, general assembly, body shops. We built all our beta vehicles, some more coming still in the next month, but as you said, the ramp will really come 2024."

The Cybertruck Will be Elon's Next Car

Cybertruck was originally announced in 2019 at the memorable event that included the unbreakable armor glass smashing. Musk was wearing the smashed glass Cybertruck t-shirt while taking questions from investors. While the wait continues, he is adamant that it will be worth it, "So it's an incredible product. I can't wait to drive it personally. It will be the car that I drive every day… it's just one of those products that only comes along once in a while, and it's really special."

The original release deadline was set for 2021. However, the production date has been delayed due to unforeseen circumstances, like a global pandemic. Nevertheless, it is a positive sign that beta vehicles have been produced. Images of what appears to be a Cybertruck were leaked a few months ago.

Recently, chief designer Franz von Holzhausen did confirm that the Cybertruck was ready for production, but it's a work in progress. Every Tesla beta product gets thoroughly examined and meticulously reviewed before the next step. But at least it's a step in the right direction.

A Look at Tesla's 2022 Numbers and Record Quarter

By Gabe Rodriguez Morrison
Tesla set new records in production and deliveries while beating analyst expectations.
Tesla set new records in production and deliveries while beating analyst expectations.
Statista

Tesla published their Q4 2022 and full-year financial results, setting new records in production and deliveries while beating analyst expectations. Tesla’s annual profit rose to $12.6 billion in 2022, from $5.5 billion in 2021. Annual revenue rose to $81.5 billion, from $53.8 billion the year prior. Tesla reported fourth-quarter revenue of $24.32 billion beating analysts' $24.07 billion estimate. The automaker also reported earnings per share of $1.19 beating analysts' $1.12 estimate.

Tesla’s stock rose more than 5% in after-hours trading following the earnings release and surged more than 10% the next day.

Tesla's Q4 2022 revenue set a new record for the company, up 59% from a year earlier. In addition to automotive revenue of $21.3 billion, Tesla recognized $324 million of deferred revenue from the company’s driver assistance systems.

FSD Beta Numbers

Tesla reported that 90 million miles have now been driven with FSD Beta, up from 58 million miles in the previous quarter. The company also confirmed that they have about 400,000 FSD Beta users in North America, a sizeable increase since the last report. With such a steep increase in miles driven and FSD Beta becoming widely available in North America, Tesla is making significant progress with its autonomous driving software.

In late 2022 and into this year, Tesla began cutting prices on its cars globally. Elon spoke about how recent price cuts have fueled a surge in demand for Tesla: “Thus far in January we’ve seen the strongest orders year-to-date than ever in our history. We’re currently seeing orders of almost twice the rate of production.” He added: “These price changes really make a difference for the average consumer.” Tesla acknowledges that average sales prices have to decrease over time because affordability is part of Tesla's mission to grow into a company that sells multiple millions of cars annually.

Price cuts will impact profitability, but margins should remain healthy, Tesla CFO Zach Kirkhorn affirmed. Tesla has wider operating margins than the industry average, which allows them to make such price cuts.

Elon issued an uncertain forecast for 2023, saying Tesla planned on 1.8 million vehicles for the year without specifying whether that was a target for production or deliveries. If the company were to deliver 1.8 million vehicles in 2023, that would result in 37% annual growth.

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Although we share official Tesla release notes, we are not affiliated with Tesla Motors. We are Tesla fans and supporters.

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View the release notes for the upcoming version 2023.2.0.5.

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Take a look at features that Elon Musk has said will be coming soon.

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