Could Postal Long Life Vehicles be Converted to Hybrids?

The U.S. Postal Service operates one of the largest fleets of vehicles in the world, about 219,000 vehicles of which about 142,000 are long life vehicles (LLVs) built by Grumman for daily mail delivery.  These vehicles were designed in 1988 to last 24 years, and have recently been extended to 30 years of service (until 2018).  Other vehicles have been tested and supplement the fleet, including Ford Windstar and Dodge Caravan minivans (including a contract to test new electric vehicles from Chrysler).

Because of the sheer number of vehicles, this fleet represents an excellent opportunity for substantial fuel savings for the USPS.  The Grumman LLV’s fuel economy is on average 17 miles per gallon, so even a bump of just a few mpgs would have a huge impact.  In fact, the USPS estimates that a 1 cent increase in the cost of gas equates to a $9 million increase in fuel costs.  This provides a substantial incentive make a shift to either more fuel efficient or alternative fuel (read as “cheaper” fuel) vehicles.

Sam Pulcrano, vice president of sustainability, told The Auto Channel, “With our fleet traveling more than 1.2 billion miles a year, the Postal Service is consistently looks for ways to reduce the environmental footprint that results from visiting every home and business in America six days a week.”  In an effort to make this shift, the USPS has ordered 900 gas hybrid (HEV) delivery trucks and 1,000 E-85 ethanol alternative fuel trucks.

While E-85 and other alternative fuels (CNG, propane, biodiesel) offer opportunities for fuel savings, converting current LLV delivery vehicles is also something to be examined.  These vehicles travel short distances (average about 25 miles/day, with lots of stop and go driving) which is a profile well suited for either HEVs or plug-in hybrids (PHEVs).  PHEVs in this situation could potentially run without using any fuel and could help reduce maintenance costs. 

Granted, full electric vehicles (EVs) obviously offer similar benefits, but converting the current fleet of LLVs is attractive because of there is a substantial investment wrapped up in these vehicles already.  Converting the current fleet of LLVs to either HEVs or PHEVs is not likely to require the expensive, more powerful, lithium ion (Li-Ion) batteries that EVs typically need, and could use the Nickel Metal Hydride (NiMH) chemistry, though this would likely reduce the mileage in all-electric mode.

This type of conversion offers opportunities on both sides of the equation.  For the USPS, there is substantial savings possible if they can reduce their fuel usage, even by only 10-15%.  On the supplier side, the USPS fleet of 142,000 vehicles is a large enough volume that being able to convert these vehicles would represent a substantial revenue source.  As with other fleets in America, however, the USPS is finding that their answer to the fuel savings question is likely to come from a variety of sources, not just converting to hybrids.