Regenerative braking in an EV: how much energy you get back and how to set it

The short answer: about a fifth of the driving energy comes back

When you lift off the accelerator or brake, an EV's motor works as a generator and sends energy back to the battery; the Department of Energy's Alternative Fuels Data Center notes that some vehicles use motor generators for both drive and regeneration. How much that recovers was measured by the European consumer program Green NCAP on 19 EVs, published by the Austrian auto club ÖAMTC in 2024. On average the cars recovered about 20% of the energy they had used for driving, from about 30% for the NIO ET7 and Hyundai IONIQ 6 to just under 10% for the Dacia Spring.

In town, with frequent slowing, even the weakest car recovered at least 15%, ÖAMTC reports; on the highway it averaged only about 10%. Downhill it can be much more: in a dynamometer run based on a real mountain road in southern Germany near the Austrian border, three test cars recovered about 35 to 50% of the energy they had used going up.

Our assessment: regenerative braking is not free energy. Converting motion to electricity and back always loses some, so the most efficient driving is anticipating traffic well enough not to slow down hard in the first place, which ÖAMTC also recommends.

Sources: [1], [2], [8]

Green NCAP: 19 EVs compared

The table lists the share of energy recovered, the highest regenerative power measured and the test weight. These are European versions tested in Europe, and several models are not sold in the US. ÖAMTC notes that heavier, more powerful cars recover more, but stresses that the extra energy needed to accelerate a heavy car outweighs that benefit. ÖAMTC's page gives no test date for the Green NCAP figures.

Sources: [1]

Levels, paddles and one-pedal driving

Most EVs let you choose how strongly they regenerate. In Kia's US manual for the 2023 EV6, the left paddle behind the wheel raises the level and the right one lowers it, from 0 to 3. Holding the left paddle activates one-pedal driving, which can bring the car to a stop; once stopped, the electronic parking brake engages automatically, for example when you shift to Park, open the driver's door or after five minutes. Pulling the left paddle again at level 3 turns on i-Pedal, which lets you speed up, slow down and stop with the accelerator alone.

One-pedal driving does not replace the brake pedal. Kia warns not to rely on it alone because the car may not stop depending on conditions, to press the brake when stopped on steep hills, and to avoid suddenly raising the level on snow or ice because the tires can slip. Polestar's US manual adds that slippery or icy roads can reduce regenerative braking.

Sources: [3], [4], [5], [6]

When less comes back: full battery, cold and ice

Kia's list of situations in which the paddles do not work includes a battery at 100% state of charge, SNOW drive mode and towing a trailer. Fueleconomy.gov notes that battery performance drops in cold weather and that this also affects regenerative braking. Our reading: expect weaker regeneration right after charging to 100% and on cold mornings, and use the brake pedal accordingly.

Kia also describes a brake-disc cleaning function that runs about ten times when you select level 0; while it runs, range and regenerative performance can be reduced, and both return once it finishes. How cold weather affects range overall is covered in “EV winter range 2026: how much you lose in the cold and what actually helps”.

1. Use a strong regeneration level or one-pedal driving in town, where it recovers the most.
2. On the highway, anticipate and coast rather than slowing hard and often.
3. Expect weaker regeneration on a full or cold battery and on ice, and keep your foot ready for the brake.
4. Don't charge to 100% right before a long descent.
5. When buying, check how many regeneration levels the car offers and how you change them.

Sources: [3], [7], [6]