Beginning in 2014, new EPA standards for emissions and fuel consumption among large trucks, including semis, will take effect. The new standards, originally proposed in 2010, require trucks to reduce their emissions by anywhere from 10 to 20 percent — and subsequently increase fuel efficiency by the same amount — by 2018.
Given that the average tractor trailer truck gets about two to three miles to the gallon of diesel fuel, even a small improvement in fuel efficiency can make a difference. One area that can make a significant difference is aerodynamics, specifically reducing the aerodynamic drag that occurs on the flat rear surface of a trailer. As the truck travels down the highway, the force of the air moving over and down the rear of the trailer creates drag, making the truck work harder and use more fuel to move forward.
However, a trailer add-on from a California-based company could make that drag a thing of the past and significantly reduce the amount of fuel used by large trucks.
Trailer Tails: A New Look for Tractor Trailers
Anyone who has driven on a highway in the last few years may have noticed trailers with trailer tails. Rather than having a box-like appearance, a trailer with a trailer tail has a three-sided “tail” attached to the rearmost portion. The top of the tail is angled downward while the sides each tilt inward. This configuration reduces the drag created by air, improving the aerodynamic efficiency of the trailer.
The tails, which only cost a few thousand dollars including installation, have the potential to reduce annual fuel consumption by as much as six percent. In fact, one company that recently installed the tails on all of its company-owned trailers, trucking giant CR England, expects to conserve as many as two million gallons of fuel per year as a result of the change. This is the environmental equivalent of offsetting the carbon emissions of more than 7,000 passenger cars.
Additional Aerodynamic Advantages
While trailer tails themselves can vastly improve fuel efficiency in large trucks, the savings add up when the tails are used in conjunction with other aerodynamic efficiency improvements, such as side skirts. According to EPA research, the combination of trailer tails and side skirts can actually reduce fuel consumption by as much as 12 percent, allowing trucks to meet the new standards ahead of schedule and without significant changes to the fleet.
Of course, aerodynamics is not the only cause for excess fuel consumption among larger vehicles. Overweight trailers not only violate Department of Transportation rules but increase the amount of fuel needed to transport the load. Experts recommend trucking professionals take steps to ensure their loads meet weight standards by paying close attention to their trailer weights and weighing loads before they reach weigh stations using portable equipment (browse all the portable truck scales available here). Taken together, a commitment to staying in weight guidelines and employing new aerodynamic efficiencies will allow trucking companies to meet the new EPA fuel guidelines — and still efficiently manage their loads and keep freight moving.
Truck image by Traci Gardner from Flickr’s Creative Commons