Stop/Start technology improves fuel economy by reducing engine idle time. As a vehicle slows to a stop, the engine is shut down but then immediately restarts when the break pedal is released so that the vehicle can accelerate without delay. Hybrid vehicles have always employed the strategy of shutting off their engines when not needed. However, manufacturers are beginning to add Stop/Start technology to non-hybrid vehicles sold in the U.S. to meet increasingly stringent fuel economy targets. Stop/Start technology is referred to by different names, such as the Mazda i-stop, the Kia Idle Stop and Go (ISG), and the Ford Auto Start-Stop. The use of Stop/Start technology on non-hybrid light vehicles increased from just 0.6% in 2012 to 4.6% in 2014.

Penetration of Non-Hybrid Stop/Start Technology in New Light Vehicles


Note: 2014 estimates are preliminary.

Fact #853 Dataset

Supporting Information

Penetration of Non-Hybrid Stop/Start in New Light Vehicles
Model YearCarsLight TrucksAll Cars and Light Trucks
Share of Production

Source: U. S. Environmental Protection Agency, Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975 Through 2014, EPA-420-R-14-023, October 2014.

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