Between 2000 and 2009, the United Parcel Service (UPS) increased the fuel efficiency across its fleet of 60,000 delivery vehicles by a relatively remarkable ten percent (with more on the way). Part of that boost is attributed to UPS' extensive deployment of alternative fuel vehicles, like the 48 Kenworth-built, liquefied natural gas- (LNG-) fueled heavy-duty trucks that the delivery company will soon add to its fleet.
In some countries, LPG (liquified propane gas) is an increasingly common fuel for automobiles due to its comparatively low cost and 15-20 percent lower emissions compared to gasoline or diesel fuel. Though some are against the practice, a few governments encourage the use of LPG through lowered taxes. In America, propane for automotive use is usually limited to large fleets, where the specialized pumping equipment can be cost effectively purchased. As we mentioned before, Roush has decided to ta