There's a lot of work going on these days to increase fuel efficiency, but most folks tend to think more about cars or light trucks, but think instead about the amount of fuel burned by the big rigs and you'll realize the benefits of making them more efficient. Lawrence Livermore National Lab and Navistar are putting the 18 wheelers in a wind tunnel to test various methods of reducing aerodynamic drag. At highway speeds, 50 percent of engine power is used just to push the truck through the air, rolling resistance accounts for only 30 percent by comparison.
Streamlining has been gaining ground for some years but the trailers are still, basically, a big box, inducing large air pressure differentials. With properly designed devices attached below and behind the trailers, drag can be substantially reduced. The benefit could be at least a 12 percent increase in fuel economy, with ever improving results down the road. Even better, these add on devices could be installed on trucks currently on the road, not just on new trucks meaning the results could come fast.
Many companies or independent operators would love to see those kinds of fuel economy gains and these kinds of aerodynamic body and trailer kits could be on the market in just a few years.