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Idle Reduction Benefits

Reducing the idling time of heavy-duty trucks and other vehicles saves fuel and money, protects public health and the environment, and increases U.S. energy security.

Saving Fuel and Money

Argonne National Laboratory estimates that approximately 460,000 long-haul trucks operating in the United States use 838 million gallons of fuel per year while idling six hours per day. That wasted diesel fuel translates into $1.4 billion annually, much of which could be saved by drivers using idle reduction technologies. Reducing idle time could also reduce engine wear and associated maintenance costs. See Argonne National Laboratory's Analysis of Technology Options to Reduce the Fuel Consumption of Idling Trucks (PDF 433 KB). Download Adobe Reader.

The total benefits are even larger when idle reduction strategies are applied to light- and medium-duty vehicles and school buses as well. When the idling of these vehicles is added to that of heavy-duty trucks, estimates of annual fuel use due to idling approach 3 billion gallons.

Protecting Public Health and the Environment

Idle reduction strategies can reduce idling-related emissions of nitrogen oxides, carbon monoxide, particulate matter, and other harmful pollutants by up to 99%. They can also reduce emission of the greenhouse gas carbon dioxide by slashing fuel consumption. See Analysis of Technology Options to Reduce the Fuel Consumption of Idling Trucks (PDF 433 KB) and Study of Exhaust Emissions from Idling Heavy-Duty Diesel Trucks and Commercially Available Idle-Reducing Devices (PDF 1.2 MB). Download Adobe Reader.

Idle reduction strategies reduce noise pollution as well. In some areas, trucks are required to limit noise at night, when they are typically idling. By reducing idle time, drivers can reduce engine idling noise and meet noise standards.

Increasing Energy Security

The United States imports more than 60% of its petroleum, two thirds of which is used to fuel vehicles in the form of gasoline and diesel. The demand for petroleum imports is increasing. With much of the worldwide petroleum reserves located in politically volatile countries, the United States is vulnerable to supply disruptions. Using idle reduction strategies to reduce national fuel consumption reduces U.S. dependence on imported petroleum and increases energy security.