2012 Kia Rio SedanEnlarge Photo
You’re probably already familiar with the effect that a hybrid drivetrain has on fuel economy, but now one of the key concepts of a hybrid drivetrain -- the ability for the engine to turn off and on automatically at stoplights -- is being introduced in conventional gasoline-engined cars.
Called stop/start technology, these systems can improve your fuel efficiency as well as improve air quality and cut pollution.
But what is stop/start technology, and do you need it?
Check out the five things you need to know about about stop/start systems below to see if you need it in your next car.
Stop/start cars aren’t hybrids
Stop/start, sometimes called light hybrid by automakers, stops and starts your car automatically when it isn’t needed, but unlike the system found in a hybrid car it isn’t backed up by a large electric motor and high-voltage battery pack.
In a hybrid car, slowing down for a stoplight normally switches off the car’s gasoline engine while recapturing the car’s kinetic energy into its high-voltage traction battery pack using regenerative braking.
But in most non-hybrid stop/start systems, the car’s engine is switched off when you slow down below a certain speed -- normally a few miles per hour -- with the car’s conventional friction brakes slow you down rather than a regenerative braking system.
When it comes to starting the engine again, a hybrid car uses its built-in electric motor to get the car moving before the engine is started again.
In a non-hybrid system, the traditional alternator and starter motor combination is replaced with a heavy duty alternator capable of both charging the car’s 12-volt battery as well as starting the car.
Stop/start cuts fuel bills, saves engine, reduces emissions
When you sit at stoplights in a traditional car, the engine continues to run even while it is standing still, meaning the longer your car is caught in traffic the more fuel it uses.
And while your car’s alternator and on-board electrical system gets charged when the engine is running, modern battery technology and more efficient car accessories mean that even if you’re sat in traffic for a long period of time, your car’s 12-volt battery shouldn’t go flat.
By switching off the engine when the car isn’t moving, a stop/start system can drastically lower air pollution and emissions, especially in cities where there tends to be a lot of congestion.
Stop/start also reduces engine wear, lowering maintenance costs and minimizing the risk of engine overheating when waiting in traffic on a hot day.