Would you like to improve your car’s fuel economy by 15%? The latest stop-drive technology from car manufacturers could help you do just that.

Stop-drive technology also referred to as start-stop technology or micro-hybrid technology takes advantage of those frequent occasions when you are sitting in your car but going nowhere, for example, stopped at traffic lights. Instead of the engine simply idling, the system switches the engine off.

When the lights turn green, the technology senses pressure on the accelerator or clutch pedal and restarts the engine.

Of course, it’s not quite that simple. The technology needs to supply power to all that auxiliary equipment in the car while the engine is stopped, radio, lights and air conditioning, so the system includes an additional battery to do just that.

The secondary battery is kept charged by a starter-generator system, which uses the force generated from braking to charge the battery. The same battery then supplies power while the petrol engine is off and provides the power to restart the petrol engine.

The system’s benefits are impressive. From an environmental viewpoint, vehicle emissions are reduced considerably, particularly in urban environments. Obviously less petrol is consumed and wear and tear on the petrol engine is reduced, idling is one of the most inefficient modes of operation.

Financially it has been estimated that the cost of installing a stop-drive system in a motor vehicle is around R10775.00 for a new car, compare this to the extra cost of R42382.00 for a “clean” diesel engine or R43101.00 for a full hybrid power train. With fuel savings estimated at between 5% and 15%, the extra cost of the stop-drive technology could be recouped in as little as two years, depending on the driving environment and annual mileage covered.

The technology was first tested by Toyota in the 1970’s on a Crown sedan, which recorded a 10% improvement in fuel consumption. But it was in Europe that the system was first fitted to production models, where Volkswagen and Fiat introduced the system in the 1980’s. Other European manufacturers began to use the technology, such as Volvo, Audi, Citroen and Alfa Romeo. Will the technology become commonly accepted worldwide? To a large extent this depends on the driving environment. In the United States, for example, most of the driving is done on highways and outside cities, where the technology is not so useful, while congested Europe seems to have already embraced the technology.

Both Audi and Mercedes Benz have models fitted with stop-drive technology available in South Africa, but it remains to be seen whether it will catch on in this country.