It was 22 degrees where I live last night, making it very tempting to give my car a few extra minutes to warm up this morning before driving my kids to school. It’s also easy to find someone sitting in their car with the engine running in almost any major parking lot, but that’s not the activity of a driver who wants to save fuel costs. Idling, which is when you let your engine run when you’re not driving the vehicle, uses more fuel than you probably think, and it generates a load of nasty emissions in the process.
How Much Fuel Does Idling Actually Use?
The U.S. Department of Energy states that idling can use one-quarter to one-half gallon of fuel per hour, depending on the vehicle and the use of accessories (such as air conditioning). With climate controls turned off, idling could cost you up to $0.03 per minute. That might not seem like a lot at first, but consider how many times you’ve started your car 20-30 minutes before leaving the house in the morning or how long you’ve waited in the school pickup line with the engine running. The costs add up more quickly than you think.
Idling Is a Big Problem in the U.S.
While we’re mainly here to talk about fuel consumption, the cumulative effects of idling personal vehicles are staggering. The more than 250 million cars, trucks, minivans, and SUVs on American roads burn 3 billion gallons of fuel and generate 30 million tons of CO2 each year, just by idling. We admit that there are situations when it’s necessary to leave your car running, but reducing idle time would have the same fuel-saving and emission-reduction effects as taking millions of vehicles off the road.
You Could Get a Ticket
Depending on where you live, idling may be illegal. Several states and cities have banned idling, including New Jersey, New Hampshire, Hawaii, Maryland, and others. New York City and parts of California also have regulations that prohibit idling in many situations.
Learn more about fuel economy and gas prices.
Tips to Reduce Idling
We aren’t telling you never to let your car idle, but there are several things you can do to reduce the time your car sits with the engine running.
✓
When to Turn Off Your Engine
Drive-Through Lines
Long waits at restaurants, banks, or pharmacies—turn off your engine or park and go inside.
Waiting for Passengers
Picking up kids or waiting for others? Turn off the engine in mild weather.
Warming the Interior
Driving warms the cabin faster than idling. Drive gently after 30 seconds of startup.
Modern Engine Health
Today’s starters and batteries handle frequent restarts. Turning off won’t damage your engine.
⏸️
Necessary Idling Situations
Traffic: Keep the engine running for safety. You can’t turn it off while in a traffic flow.
Defrosting: Winter window frosting may require a brief idle to clear visibility safely.
Emissions Testing: Some inspection stations require idling to maintain engine operating temperature during testing.
💡
Technology Solutions
Hybrid-Electric Vehicles
Engine shuts off automatically when stopped and can move on electric power alone.
Stop-Start Technology
“Mild hybrid” or stop-start systems increasingly available automatically stop the engine at red lights and restart on demand.
🚌
Protecting Children’s Air Quality
Vehicle emissions are more concentrated near the ground where children breathe. Reducing idling at schools and pickup zones protects developing lungs and helps prevent asthma and respiratory illness.
Be the Example
Turn off your engine at drive-throughs and while waiting. Show others the simple habit.
Talk to Schools
Encourage anti-idling policies and signs at school bus areas and parent pickup zones.
Inform Businesses
Suggest drive-through managers post reminders about idling’s environmental impact.
Know Local Laws
Check if your area restricts idling. Some regions fine drivers for unnecessary engine running.