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What is idle reduction?

Idle reduction is typically used to describe technologies and practices that reduce the amount of time heavy-duty trucks idle their engines. However, light- and medium-duty vehicles and school buses can benefit from idle reduction strategies as well. Reducing idle time saves fuel, engine wear, and money while reducing emissions and noise.

About 500,000 long-haul trucks cross U.S. highways each day. Truckers are required to take a 10-hour rest after 11 hours of driving. As the trucks idle their engines during rest periods to provide heating, cooling, and electrical power and to keep the engine warm and the battery charged, they use approximately 838 million gallons of fuel per year.

A variety of technologies are employed to reduce this fuel use. Onboard equipment such as automatic engine stop-start controls and auxiliary power units can be used wherever the vehicle might be. Truck stop electrification enables trucks to hook up to stations that provide power and other amenities.

Additional strategies are available for light- and medium-duty vehicles and school buses. When the idling of these vehicles is added to that of the heavy-duty trucks discussed above, estimates of annual fuel use due to idling approach 3 billion gallons.