The technology behind Stop-Start Vehicles (SSV) is based on a simple technique used by many economy-minded drivers ever since the first traffic jam; namely, shut off the gas-consuming engine in your vehicle when you will be idling or sitting still for any length of time. After all, when the engine in your car is not running, it’s not consuming fuel.

What a Start-Stop Vehicle Is, and Isn’t

In a SSV, the otherwise traditional gasoline-powered engine actually shuts itself off when the vehicle slows down or comes to a stop. When the driver releases the brake pedal (or the clutch in some cars with manual transmissions), the engine quickly restarts – again, automatically.

According to energy and technology site Green Car Congress, SSVs offer 5% to 10% reductions in both fuel consumption and CO2 emissions. A study by the U.S. Department of the Treasury estimates that traffic congestion caused drivers to burn an extra 19 billion gallons of fuel in 2011 alone. That’s nearly 5% of all gasoline used annually. Other studies have shown that drivers on a typical 20 mile commute will encounter an average 10 to 15 red lights and stops signs which can add as much as 15 minutes of time their car engine is idling and wasting gas.

Although sometimes called “micro hybrid” or “idle-stop” technology, a start-stop-only vehicle is not considered an actual hybrid, since it doesn’t use electric motors of any kind for propulsion. Manufacturers selling non-hybrid SSVs in North America include: Kia, BMW, Mercedes-Benz and Porsche.

Manufacturers offering hybrid models with available start-stop systems include: BMW, Cadillac, Chevrolet, Ford, GMC, Honda, Hyundai, Lexus, Lincoln, Mercedes-Benz, Nissan, Porsche, Toyota and Volkswagen.

Savings Outdistance Cost

Surprisingly, start-stop systems are relatively inexpensive. For example, Ford Motor Company announced in April that its Auto Start-Stop system on the non-hybrid 2013 Fusion will add only $295 to the cost of each vehicle. With a projected 47 mpg (vs. 37 for the non-start-stop Fusion model) this added cost can quickly be recovered in fuel savings alone.

Start-stop vehicles may soon become even more attractive to new car buyers. That’s because, as GreenCarCongress.com warns, several communities across the U.S, including Denver, Colorado and Ann Arbor, Michigan, for example, are considering citywide ordinances that ban excessive engine idling. How they intend to enforce such regulations isn’t clear.

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