(R)EVOLUTION - Stop & Start – The simple idea that paved the way for the hybrid era

Stop & Start – The simple idea that paved the way for the hybrid era

In the history of the automobile, each period has seen the emergence of innovations directly linked to the concerns of its time. In the 1980s, when the energy crisis reminded motorists and manufacturers of the importance of fuel efficiency, some engineers came up with a bold solution: automatically switching off the engine during prolonged stops, then restarting it instantly as soon as the driver requested it again.

The idea seemed simple, but it was a minor revolution. In the city, a vehicle can spend long minutes at a standstill – at a red light, in a traffic jam or during a short parking stop – while continuing to consume fuel and emit exhaust gases unnecessarily. Switching off the engine at these times, without the driver’s intervention, would reduce both fuel consumption and pollution, while making the vehicle’s operation more efficient.

For a long time, this principle remained at the experimental stage. The mechanical and electronic technologies of the time struggled to offer the reliability and speed required for everyday use. But research continued, and in the early 2000s, the device reached a decisive milestone: it was industrialised under the name Stop & Start. Initially reserved for city cars, where its benefits are most obvious in urban environments, it gradually became established in wider segments.

The system works on the basis of a perfectly orchestrated mechanism: when the vehicle is stationary, the engine cuts out automatically, while essential equipment (radio, ventilation, lighting) remains powered. When the driver presses the clutch or releases the brake pedal, the engine restarts immediately, with no perceptible delay. The system is designed to be completely transparent to the user, requiring no special action.

Widespread in the 2010s, Stop & Start has become an essential feature, adopted by almost all manufacturers. It contributes significantly to reducing fuel consumption and CO₂ emissions, particularly in urban areas, while supporting new environmental regulations.

But its importance goes beyond its immediate effectiveness. Above all, Stop & Start paved the way for modern hybrid engines, which operate on the same principle of intelligent management of stop and restart phases, but on a more advanced scale, incorporating batteries and electric motors. In this sense, it forms a genuine link between traditional combustion engines and today’s sustainable mobility technologies.

Thus, this system, long perceived as a technological curiosity, has become a matter of course for millions of drivers. Stop & Start perfectly illustrates how a simple idea, born out of a desire for energy efficiency, can bring about lasting change in usage and pave the way for the future of the motor car.