Cadillac ELR is an electric vehicle, and EVs as you know do no have a transmission as such. But the ELR still has two paddle shifters behind the steering wheel. In this car those paddle are utilized for the “Regen on Demand” system. The Mercedes SLS Electric Drive Concept also uses this feature.

Regen on Demand allows the driver to temporarily regenerate energy and store it as electricity in the battery pack for later use. Normally, regenerative brakes should operate automatically when you lift your foot off the gas pedal or engage the brakes, but this system provides vehicle deceleration that is more than what a typical vehicle experiences while coasting. Caddy says that gives you the same feeling as downshifting in a performance car.

Once engaged, Regen brakes convert the kinetic energy of decelerating into electricity and store it in the ELR’s T-shaped battery pack underneath the floor. Relying only on electricity, the ELR can cover a distance of 35 miles before the onboard gasoline engine kicks in.

The system has a standard 4-channel anti-lock braking system and includes electronic Brake Force Distribution, which uses independent rear control for improved stability and braking during cornering.

“Regen on Demand enables ELR drivers to actively re-capture energy when slowing down, such as when  approaching slower traffic or setting up for a tight turn,” said Chris Thomason, ELR chief engineer. “This allows the driver to take more active role in the electric vehicle driving experience.”