The Carlisle Mosquito Online

Friday, September 11, 2009


Green Corner Old habits (and myths) die hard

Back in the days before modern automotive batteries, engines, starters, and electronic ignition systems, the conventional wisdom was that engine idling was beneficial and cost-effective from the standpoint of mechanics and fuel consumption. What was true several decades ago no longer applies today, but habits and misinformation from the past continue to guide much of our “idle” behavior.

Research from the US Environmental Protection Agency (EPA) (, the Hinkle Charitable Foundation ( and the Environmental Defense Fund ( indicates that dispelling the following engine idling myths would go a long way toward improving the quality of our air, water and soil, while also reducing health risks and saving energy and money.

Myth: Cars should run in an idling mode for several minutes before being driven.

Fact: Today’s engines need only a few seconds of idling time before they can be driven safely. Driving your car at moderate speed for a few miles after starting your engine is the best way to warm up all mechanical parts and catalytic converters for optimum operation.

Myth: Repeatedly restarting your car wears out the engine and drains the battery.

Fact: Not only does restarting your engine not cause wear and tear on the engine or excessively drain modern batteries, idling actually causes the engine to operate very inefficiently, potentially degrading its performance and reducing mileage over time.

Myth: Restarting your engine wastes more gasoline than idling.

Fact: The break-even point in terms of gas usage for idling versus restarting an engine is ten seconds. Idling longer than ten seconds uses more fuel than restarting your engine, wasting gas and money in the process.

Myth: Engines need to keep running to keep cabins warm/cool.

Fact: Driving your car is the fastest, most fuel efficient way to warm or heat the interior. Most car interiors are heated or cooled within five minutes of driving and stay warm or cool for five minutes or longer with the engine off.

It’s the law

It comes as a surprise to most state residents that anti-idling legislation has been on the books in Massachusetts since 1972 (M.G.L. Chapter 90, Section 16A). The law has gained new life recently at the state and local levels as a result of heightened concerns about the negative impact of idling on health, energy use and the environment.

Health Issues

While all voluntary idling is covered by the legislation, idling school buses have become a major focus of recent enforcement efforts because of the increased health threat to school-aged children from exposure to diesel exhaust. Diesel exhaust is particularly harmful because it contains a high concentration of particulate matter – fine particles of inhalable toxic substances linked to asthma, bronchitis, and various lung diseases, according to the EPA. The NE Asthma Regional Council states that children are especially vulnerable to air pollution because they breathe in 50% more air per pound of body weight than adults.

Wasteful ways

While some idling is necessary (e.g. at traffic lights, stop signs, during engine repairs, etc.) there are many examples of the “voluntary” or unnecessary idling that is the target of anti-idling legislation.

On average, Americans engage in unnecessary idling for 5-10 minutes a day, as readily observed at bank, pharmacy and fast-food drive-through lanes, and school pick-up and drop-off areas across the country. In addition to school grounds, Carlisle idling “hot spots” include the Post Office, Transfer Station, Kimball’s and Ferns as drivers leave engines running while they run errands.

Five minutes of idling per U.S. vehicle adds up to 3.8 million gallons of gasoline burned on a daily basis or 1.4 billion gallons consumed annually while standing still, according to the Hinkle Charitable Foundation’s Anti-Idling Primer. This waste of a finite resource also makes a dent in our pocketbooks, with an estimated $30 to $60 per car evaporating into thin air along with exhaust fumes .

Environmental toll

The needless burning of 1.4 billion gallons of gasoline a year in the U.S. alone releases approximately 13 million tons of heat-trapping, carbon dioxide into the earth’s atmosphere, adversely affecting the air, water and soil quality of all nations and adding to the growing problem of global warming, the Anti-Idling Primer states.

The bottom-line? Idling longer than ten seconds gets you nowhere while wasting fuel and money, polluting the environment, increasing CO2 emissions, and harming our health.

The good news is that changing an idling habit is as simple as turning a key.

© 2009 The Carlisle Mosquito