Transport Partnership
                               A Glance at
           Clean Freight Strategies
                    Idle  Reduction
   Reducing unnecessary truck idling can save fuel, reduce greenhouse gas emissions, cut air pollution, and save money.
   A typical long-haul combination truck that eliminates unnecessary idling could save up to 1900 gallons of fuel each
   year. Saving this much fuel annually would remove 19 metric tons of carbon dioxide (a greenhouse gas), reduce A/Ox
   and PM emissions, save nearly $3,000 in fuel costs, and lower engine maintenance costs.
   What  is the challenge?
   Many long-haul truck drivers idle their engines during
   rest periods to:
        provide heat or  air conditioning  for  the
         sleeper compartment
        keep the engine warm during cold weather
        generate electrical power for appliances

   Studies by EPA and others suggest that long-haul
   combination trucks often idle up to eight hours per
   day, over 300 days per year. Typical combination
   trucks consume 0.8 gallons of  diesel fuel during
   each hour of idling, using as much as 1,900 gallons
   of fuel each year per truck.

   Using  a heavy-duty truck engine  to power cab
   amenities   is  inefficient.  It  consumes  fuel
   unnecessarily;  increases fuel costs,  and causes
   emissions that contribute to climate change and air
   pollution. Today's diesel engines do not need to idle
   for long  periods of time  before and  after driving.
   Unnecessary engine idling also contributes to engine
   wear, which increases truck maintenance costs, and
   shortens engine life.

   What  is the solution?
   Several technological options can assist drivers in
   reducing truck idling.

        Auxiliary power units (APUs)  are mounted
         externally on the truck cab. An APU typically
         consists of a small combustion engine and
         generator combination  that  can  provide
         power  to the truck when the main engine is
         shut off. Electricity from an APU can be used
         to  power heating,  air  conditioning,  and
         electrical  accessories  for  the cab  and
        Automatic engine idle systems start and stop
         the truck engine automatically  to maintain  a
         specified cab temperature, or to maintain
         minimum  battery  charge. Drivers  typically
         activate the system in  the   evening and
         program a desired temperature range.
        Truck stop electrification allows trucks to use
            electrical power from an external source. At
            properly equipped  truck stops, drivers can
            shut the main truck engine off and plug into
            an  electrical outlet that provides power for
            heaters, air conditioners, marker lights, and
            other  accessories. Trucks  need  to  be
            equipped with the  required internal wiring,
            inverter system, and HVAC system to take
            advantage  of truck stop electrification.
           Advanced  truck  stop  electrification  also
            provides electricity from an external source,
            but doesn't require the truck to be equipped
            with special systems. Truck parking bays are
            installed with equipment that provides the
            cab with  electrical power,  and  heating,
            cooling,   and  other   amenities   like
            telecommunication  hook  ups,  through  an
            external console  that fits into the truck's
            window frame. The truck-side console has
            temperature controls, an  air  supply  and
            return pipe, a credit card reader, keypad, and
            100 VAC outlet.

     The results are in ...
     The amount of idling varies widely among trucks by
     season, type of operation, and driver practices.  A
     typical long haul combination truck could idle  up to
     2,400 hours  per year, which would use over 1,900
     gallons of fuel. Using an APU instead of idling the
     engine could reduce this fuel use by 75 percent and
     eliminate over $2,000 in fuel costs plus over $300 in
     engine maintenance costs each year. Truck stop
     electrification can  potentially  eliminate all engine
     idling. However, because the systems can be used
     only at stations outfitted with appropriate equipment,
     not all  the  potential  savings  can  be obtained
     immediately. Additional  truck stop  electrification
     spaces are planned along major interstate corridors.

     Next steps
     Truck  fleets  should  examine  engine-operating
     records to determine the percent of time spent idling
     to determine potential fuel  and cost-saving benefits.
     Truck fleets may also check the availability of truck
     stop electrification  facilities along frequent routes.
i.S. Environmental Protection Agency  Office of Transportation and Air Qualh
February 2004. EPA420-F-04-009.  For more Information,, visit: www.epa.gov/smartway