Idle Reduction Benefits and Considerations

Reducing vehicle idling time saves fuel and money, cuts harmful emissions, and increases U.S. energy security. Decreasing idle time can also reduce engine wear and associated maintenance costs.

Saving Fuel and Money

A photo of an open vehicle trunk with a black auxiliary battery pack inside.

Air conditioning and power can be supplied by an auxiliary battery pack unit that fits neatly in the trunk.

Argonne National Laboratory estimates that more than one million long-haul heavy-duty trucks idle during required rest stops. As the trucks idle, they use more than one billion gallons of fuel per year. Accounting for all road vehicles, from passenger cars to heavy-duty trucks, Argonne estimates that more than 6 billion gallons of gasoline and diesel combined are lost to idling every year. Even when fuel prices are as low as $2 per gallon, that wasted fuel translates into more than $11 billion annually—much of which could be saved through the use of idle reduction technologies.

Cutting Harmful Emissions

Idle reduction strategies can reduce emissions of carbon dioxide, nitrogen oxides, carbon monoxide, particulate matter, and other harmful pollutants.

Idle reduction strategies also reduce noise pollution. In some areas, heavy-duty trucks and trains are required to limit noise at night. By reducing idle time, drivers can comply with noise standards.

Increasing Energy Security

In 2017, the United States imported 19% of the approximately 19.8 million barrels of petroleum per day it consumed. Because transportation accounts for nearly three-fourths of total U.S. petroleum consumption, using idle reduction strategies to reduce fuel consumption can have a direct impact. This not only supports U.S. energy independence but also helps reduce the impact of international supply disruptions. All of this adds to our nation’s energy security.

Complying with Laws and Ordinances

Many states have idle reduction laws and incentives. In addition, many counties and municipalities have enacted idling restrictions. View the Clean Cities IdleBase to access a database covering idling laws, from the local level to the state level spanning all types of on-road vehicles. For information specific to heavy-duty trucks, see the American Transportation Research Institute's Idling Regulations Compendium. It is available as a handy cab card.