When is it worth it to turn off the car, instead of idling?
Laura Johnston, of The Plain Dealer, tackles the problem of letting your car idle. While car idling is not the biggest contributor to global warming, it's something we can change easily according to Johnston, unlike the length of our commute or the fuel efficiency of our SUVs. I would argue we can change the lengths of our commutes and the fuel efficiencies of our cars, but I do agree, perhaps not as easily. Anyhow.
Idling is estimated to use about 4% of an engine's gasoline, so eliminating idling would cut a car's carbon emissions by the same amount. And, of course, it could even save you money, especially in our current era of high gas prices. So when is it worth it to turn the car off while you wait? If you're going to be waiting somewhere for more than 30 seconds, it uses less gas to restart than to idle.
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