Next comes the shape of the vehicle. Aerodynamic drag accounts for 2.6% of the energy losses. As the speed of a vehicle increases, the drag caused by expending energy to push air out of the way increases. By designing the shape of a vehicle for smoother air flow, significant drag reduction can be achieved.

Rolling resistance is another loss encountered in a vehicle. It accounts for 4.2% of the losses. This rolling resistance is a measure of the force necessary to move the tire forward. To counter this, tires technologies like thread and shoulder designs, and the use of improved materials on the tire belt and traction surfaces are being developed.

For passenger cars, a 5~7% reduction in rolling resistance increases fuel efficiency by 1%. However, these improvements must be balanced against traction, durability and noise.

Related to the driver's behavior is braking loss. This can account for as much as 5.8%. Each time a vehicle moves forward, the vehicle's drivetrain must provide enough energy to overcome the vehicle's inertia. This inertia is directly related to the weight of the vehicle. So for lighter vehicles, less energy is expended to overcome the inertia of the vehicle compared to a heavier vehicle. The less a driver brakes, the less energy is expended to move the vehicle again.

As you can see, there are many factors that can affect the fuel efficiency even of similar vehicles. Factors like the vehicle condition, tire pressures and design, driver's habit, planning trips, reducing excess loads, avoiding drag, idling at peak traffic and many others can affect the efficiency.

With a better understanding of the measures you can control, you should be able to achieve the best optimum efficiency in your vehicle and save money in the process.

About the Author
Thomas Yoon specializes in cartoon illustrations that will make an impact on people's opinions.
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