According to the National Renewable Energy Laboratory (a part of the United States’ Department of Energy), an evaluation of hybrid electric tractor trailers has revealed that the hybrids achieve considerably better fuel economy than conventional non-hybrids.
12% Reduction in Fuel Costs
“During our 13-month study, the hybrid tractors demonstrated 13.7 percent higher fuel economy than the conventional tractors, resulting in a 12 percent reduction in fuel costs for the hybrids,” NREL Senior Project Leader Michael Lammert said.
Additional Test Information
This project is called the Coca-Cola Refreshments Class 8 Diesel Electric Hybrid Tractor Evaluation. The vehicles were class 8 diesel-electric hybrids operated by Coco-Cola refreshments.
In addition to fuel economy and fuel costs, the NREL also collected vehicle maintenance and other performance data.
“Our analysis identified key variables on trucking routes—such as idle time, kinetic intensity, and average speed—that, if taken into consideration, can help Coca-Cola Refreshments optimize the use of its hybrid vehicles on routes where they offer the greatest fuel economy benefits,” Lammert said.
This is reminiscent of the fact that the way in which vehicles are driven, and the routes that are taken for trips, both affect fuel efficiency considerably. The more time you spend driving on a highway, and the less time you spend on city driving, the more fuel you save.
This is because city driving requires much more frequent braking, acceleration, and cornering (which also requires braking and acceleration) than highway driving. All these require extra energy, and braking costs drivers momentum by dissipating it as heat.
“We see cost as the number one barrier to companies using advanced technologies,” Lammert said. “Testing like this helps companies understand whether these vehicles are going to save them money over the long run.”