BENTONVILLE, AR --– Wal-Mart Stores Inc. said it will test two new types of heavy-duty commercial hybrid trucks and two different alternatively fueled heavy-duty trucks, as a part of the company's efforts to develop a more sustainable trucking fleet.

The new trucks include:

-- A full-propulsion Arvin Meritor hybrid that will initially operate in the Detroit area. This dual-mode diesel-electric hybrid is believed to be the first vehicle of its type.

-- Fifteen trucks operating in a Buckeye, AZ, distribution center will be converted to run on Reclaimed Grease Fuel, made with the waste brown cooking grease from Walmart stores. In addition, the remaining trucks located in the Buckeye distribution center will operate on an 80/20 blend of biodiesel made of reclaimed yellow waste grease.

-- Five Peterbilt Model 386 heavy-duty hybrid trucks with diesel-electric hybrid power systems, developed by Eaton Corp. and PACCAR, which will be based in Dallas, Houston, Apple Valley (CA), Atlanta and the Washington/Baltimore regions.

-- Four Peterbilt Model 386 trucks and one yard truck that operates only on the distribution center property will operate on liquid natural gas. These trucks are part of a partnership with the Mojave Air Quality Management District and will operate out of the distribution center in Southern California.

"In order to meet our goal of doubling our fleet efficiency, we are taking an active role in the development of these technologies,” said Chris Sultemeier, senior vice president of transportation for Wal-Mart Stores Inc. "We look forward to determining if these technologies will help reduce our environmental footprint, are viable for our business and provide a return on investment."

Wal-Mart said it achieved more than a 25-percent increase in efficiency within its private fleet between 2005 and 2008, surpassing one of the company's stated sustainability goals. By reaching this goal, Wal-Mart has reduced its carbon dioxide emissions and its fuel use. This goal was reached by using a combination of new, innovative technologies, better delivery routes and by loading its trailers more efficiently, the company said.

Now, Wal-Mart is working toward its goal of doubling its fleet efficiency by 2015, from its 2005 baseline. Part of this pilot program is to determine if alternatively fueled trucks can help move Wal-Mart toward that goal in addition to reducing environmental impacts.

Wal-Mart has actively engaged several suppliers to develop and test these new technologies, the company said. This includes Arvin Meritor, Eaton, Peterbilt and International as well as smaller companies. Wal-Mart will test these new technologies throughout 2009.