Roof racks weight heavily on fuel economy, study shows image

A new study makes you think twice if you still want a roof rack on your car, as it can drag up the fuel consumption as much as 25 percent.

A roof rack is quite a handy accessory for your car to carry around, as it can be very useful when you want to take with you bulky things that do not fit into the boot. While it is a convenient tool, it may cost you more than you would have thought. According to a study made by Lawrence Berkeley National Laboratory researcher Alan Meier, working with Yuche Chen of the National Renewable Energy Laboratory, roof racks were responsible for 0.8 percent of light-duty vehicle fuel consumption in the United States in 2015, equivalent with 100 million gallons of gasoline.

Their study, published recently in the journal Energy Policy, showed that the aerodynamic impact of the roof racks over a passenger car may increase the fuel consumption up to 25 percent, depending on what is hooked on top of the vehicle. Furthermore, they are projecting the use of racks to jump by about 200 percent by 2014.

It was also found out that driving on the highway carrying around unloaded cross roof racks has the biggest impact on fuel, because the total miles traveled with unloaded racks is four to eight times higher than that for loaded ones. “These results suggest that some fuel-saving policies should focus on reducing the number of vehicles driving with empty racks,” the researchers write. They believe that better designed and more aerodynamic efficient racks alongside with government policy would help to save 1.2 billion gallons of gasoline over the next 26 years.