In 2008 FedEx set a target of increasing the fuel efficiency of its global vehicle fleet 20 percent by 2020 from its 2005 levels. Eight years on, it's already improved by 22 percent.

Now it's raising the goal to improve fuel efficiency 30 percent by 2020, both for vehicles and aircraft.

FedEx says it's seen the biggest improvements in fuel efficiency from small but smart changes in how it operates and builds vehicles. Matching the right vehicle to each route, for example, is expected to cut fuel use by 20 million gallons this year.

Another simple strategy is to make sure vehicles have "right-sized" engines. Outfitting a vehicle with the smallest engine that can do the job makes them 70 to 100 percent more fuel efficient than the truck it replaces. So far, about 10,000 of such vehicles are in service — more than a third of those delivering packages in the U.S.

The company is also moving toward composite bodies that significantly lower a vehicle's weight. Combined with a smaller engine, this change will cut fuel use by 35 percent compared to conventional walk-in vans.

About 35 percent of older diesel engines have been converted to more efficient, cleaner versions that comply with updated Environmental Protection Agency diesel emissions standards issued in 2010.

The company relies much less on using hybrids and electric vehicles. It has just 360 hybrids and 200 EVs made by Smith Electric. They are used on dense urban routes where the use of regenerative braking and electric motors significantly improves fuel efficiency when there's lots of starting and stopping.

"FedEx Express follows a three-tiered strategy to improve the fuel efficiency of its fleet: Reduce, Replace and Revolutionize," says Dennis Beal, vice president of global vehicles at FedEx Express, in a statement. "This holistic approach to fleet management allows us to develop vehicle technologies for the future while maximizing the conventional vehicles we operate today."

Among FedEx's most impressive achievements is the 175,000-square-foot green roof at its cargo facility at Chicago's O'Hare International Airport.

Although improving fuel efficiency by 22 percent is impressive for a global fleet in five years, it also indicates the company could be moving much faster. It's great that FedEx raised the target, but these are still incremental improvements, not "standout leadership."

Competitor UPS, as well an incremental mover, also uses small but important changes in driving habits to increase efficiency, and it has 2,500 hybrid and other alternative-fueled vehicles in its fleet.

Photo of a FedEx truck provided by ronmclinden via Flickr.

This story is reprinted with permission from Sustainable Business.