MIT  Center for Transportation and Logistics, utilizing data from Staples, found  that the use of electric delivery trucks can cost between 9 to 12% less to operate  than diesel-powered trucks.

However, the study  noted, the cost of an electric truck can be triple that of a truck with a  standard internal-combustion engine. An electric truck can cost nearly $150,000  compared to about $50,000 for the same type of truck with a standard internal-combustion  engine.

“There has to be a good business case if there is going to  be more adoption of electric vehicles,” said Jarrod Goentzel, director of the  Renewable Energy Delivery Project at CTL and one of four co-authors of the new  study. “We think it’s already a viable economic model, and as battery costs  continue to drop, the case will only get better.”

  Another of the paper’s co-authors, Clayton Siegert, a 2009 graduate of the  CTL’s master’s of engineering in logistics program and a member of the  Renewable Energy Delivery Project, presented the results in January at the IEEE  Power and Energy Society Innovative Smart Grid Technologies Conference, in  Washington.

The study uses data from Staples and ISO New England, the  organization that runs New England’s electric power grid, to model the costs  for a fleet of 250 delivery trucks. Researchers examined scenarios in which the  whole fleet used one of three kinds of engines: purely electric, hybrid  gas-electric and conventional diesel. They assumed each truck was driven 70 mi.  a day for 253 days a year, with diesel at $4/gal.

The study found that the operational cost of an electric  truck enabled to use a vehicle-to-grid (V2G) system is about 68 cents per mile,  compared to 75 cents for internal-combustion trucks. Researchers added that  most of the savings scale down to the individual vehicle, so companies don’t  need big fleets to save money.

The study found that internal combustion engines averaged  10.14 mpg., compared to 11.56 mpg. for hybrids, and the electric-only trucks  averaged 0.8 kilowatt-hours per mile.

The researchers also modeled a V2G system in which the truck  batteries were plugged into the electric grid for 12 hours a night. They found  that businesses could earn about $900 to $1,400 per truck per year in V2G  revenues in current energy markets, equal to a 7 to 11% reduction in vehicle  operating costs. Firms would also save on brake maintenance because electric  trucks cause less wear and tear, they said.

In a V2G system, vehicle batteries are plugged into the  electric grid overnight to enhance the electric system’s reliability, and the  truck owners are paid by utility firms for their power services. The trucks  help improve reliability because utilities can depend on them to plug in at  certain hours – as opposed to electric passenger vehicles, which consumers plug  in at more random times.

MIT says several utility companies are testing V2G systems.

Staples’ director of fleet equipment, Michael Payette, said  the MIT analysis corresponds with his company’s findings so far, although it is  still early in Staples’ post-deployment analysis. He also said he was surprised  by drivers’ response – not only do they accept the electric trucks, they say  they don’t ever want to drive diesel again.

Staples currently uses 53 all-electric trucks from Smith  Electric Vehicles in several U.S. cities. Last July, it joined the Obama  administration’s National  Clean Fleets Partnership, under which companies work with the Dept. of  Energy to develop a comprehensive strategy to reduce petroleum and diesel use  in their fleets.

At the time Staples said it had increased the fuel economy  of its fleet by more than 20% since 2007 through fuel-saving steps such as  automatically limiting truck idling to no more than 3 minutes and limiting the  top speed of its vehicles to 60 miles an hour.