Eastbound and Down
Whether it is the finished product or a component to produce a finished product, it probably spent time being transported by truck. The trucking industry criss-crosses the globe everywhere there are roads and even some areas where there are not. Goals of zero emission trucking fleets are far from reality today but increasing the efficiency of trucking by reducing drag lowers costs and reduces emissions.
Due to the size of the global trucking fleet, even small reductions add up in a big way. Structural additions to semi-trailers change the flow of air and when designed thoughtfully can increase fuel efficiency by reducing drag. When driving, you have probably encountered trucks and felt the waves of air buffing your vehicle as you come close to the truck. By adding wheel covers, skirts, or tails to the truck and trailer, the aerodynamics can be increased. By being more aerodynamic, less fuel is required which in turn reduces the emissions being released. This technology is available now and will continue to reduce the energy required to transport goods even when non-carbon fuels become the norm.
Companies, including Freight Wing, Nose Cone, ATDynamics, and Transtex Composite, provide products that reduce aerodynamic drag. Studies continue to show fuel reductions that may surpass 10%. Results are highest when using multiple technologies such as skirts and tails. The Internationally recognized standards organization, SAE International, set the guidelines for proper testing and the reliable comparison of data.
Skirts are placed under a semi-trailer length-wise between the wheels. The skirt is essentially a fairing that increase the aerodynamics by moving air along the side and reducing poor flow underneath the trailer. While the skirt has clearance over the road, the bottom is typically made of a flexible material to withstand impact with obstacles such as snow and curbs when making wide turns.
Tails are the additions most likely to turn heads. A tail is placed on the rear of the trailer to increase aerodynamics. A tail must be able to be moved quickly and easily to not interfere with the loading and unloading of the trailer. By tapering the airflow at the rear of the trailer a tail reduces drag.
The movie “Smokey and the Bandit” was released in 1977. Notably, even with a fuel crisis developing in the late 70’s, the movie shows gas prices of well under $1 per gallon (USD). The plot of the movie revolves around a high-speed trucking run to deliver beer which, spoiler alert, is accomplished with little time to spare. If they had had a skirt and tail on the truck, possibly they could have saved a stop for fuel and arrived even sooner.
Photo Credit: Rob Bulmahn