One out of every five cars is expected to feature innovative engine stop-start systems by 2012, predicts the chief of one of the world’s largest auto suppliers. Stop-start systems shut down the engine when the vehicle is stationary, such as when sitting in heavy traffic, and automatically restarts it when the clutch is released and the car is put into gear.

The prediction comes from Bosch chairman Dr Bernd Bohr, who spoke recently with What Car? Magazine. Bosch developed the stop-start system that was introduced earlier this year in the updated BMW 1-series hatch, and not only does it save fuel but it also reduces carbon-dioxide emissions by up to 8%.

According to Bohr, “the technology will become increasingly popular and will make up 20% of the market as soon as 2012.”

A similar system will soon appear on all new Minis starting from August, and Daihatsu is expected to introduce the feature in its Charade for the 2008 model year.