Skip advert
Advertisement

A to Z of Car Tech: R is for rear-wheel-drive and regenerative braking

The letter R in our A to Z of car cech series examines regenerative braking, rear-wheel-drive and more…

The technology contained within the modern motor car can be both fascinating and slightly baffling. Most such technology exists to make our cars safer, more efficient and just better than ever to drive but some of it can be quite confusing for the average motorist. In this A to Z series we will attempt to unravel the mystery of technology that is the modern motor car. This week, we’re visiting the letter R…

Advertisement - Article continues below

R is for…regenerative braking. Used by everything from a modern Formula One car to a Formula E car - and by hybrids and fully electric vehicles as well - regenerative brakes are a clever way of creating and then storing the energy that’s produced when braking.

Such systems work by converting the kinetic energy that a vehicle produces when braking, more often than not using an electric motor, and then storing it in a battery pack, or occasionally in a spinning flywheel.

This energy is then reissued via the same electric motor whenever it’s required, for example when the driver re-applies the throttle after braking.

Some regenerative braking systems will also produce small amounts of energy by tickling the brakes in certain circumstances, even when the driver isn’t pressing the brake pedal, such as when going down a steep hill.

R is for…rear-wheel-drive. In theory, rear-wheel-drive is still the purest layout to have - be that in a front-engined car or even a mid or rear engine one - because by not putting any drive through the front wheels, the steering system remains unaffected by the throttle, and is therefore clearer in its response.

Most rear wheel-drive cars will use longitudinally mounted engines that live in the nose of the car. Power is then sent to the rear wheels from the engine’s crankshaft via a prop shaft, which then connects to a differential at the rear axle, and then to the driveshafts and so on.

All mid or rear-engined cars are either rear or four-wheel-drive. The idea of a mid-engined front-wheel-drive car would, after all, seem like the answer to a question no one has ever bothered to ask.

Next, the letter S…

A-Z of car tech
Skip advert
Advertisement
Skip advert
Advertisement

Most Popular

Jaecoo 7 recalled: a quarter of all brand’s 2025 UK cars going back to dealers
Jaecoo 7 - front action

Jaecoo 7 recalled: a quarter of all brand’s 2025 UK cars going back to dealers

The Chinese brand has initiated a recall for roughly 7,500 Jaecoo 7 models due to an incorrectly attached wiring harness clip
News
6 Mar 2026
Are car headlights too bright? How hi-tech LED lights prioritise the driver but risk dazzling everyone else
Vauxhall Grandland - lights on

Are car headlights too bright? How hi-tech LED lights prioritise the driver but risk dazzling everyone else

LED headlamps on cars may improve visibility at night, but some people say they’re too bright. We investigate the issue and what can be done
Features
9 Mar 2026
New Mercedes GLA to challenge compact SUV elite with cutting-edge CLA tech
Mercedes GLA exclusive image - front

New Mercedes GLA to challenge compact SUV elite with cutting-edge CLA tech

Our exclusive image previews how the Mk3 Mercedes GLA will look when it arrives later this year
News
9 Mar 2026

Find a car with the experts