The car as a mode of transportation is one of the most inefficient.
That must sound like blasphemy to most people who consider the car as the anchor of the modern civilization.
But it’s true.
Here are the facts: In order to transport a human being who weighs perhaps 75 Kg, the fuel has to actually transport metal and plastic and rubber weighing over 10 times that! That is, the car uses over ten times the fuel for transporting the supporting infrastructure than for the person sitting inside.
Just imagine the following scenario: You are at a shop to buy a product that costs, say, $10. The clerk at the payment counter hands you a bill for $125. You are shocked, but the clerk politely points out that the carry bag in which your product is placed costs $115. Doesn’t this sound ridiculous? Well, then the car as a medium of transport should, too!
This is one of the reasons motorbikes give you a much higher mileage, as they have to transport far less non-human weight for the same distance! (Motorcycles weigh typically about 250 Kg, while a car typically weighs about 1.5 T).
It is thus obvious that if the weight of the car is brought down significantly, a corresponding increase in fuel savings is possible.
A 10% reduction in vehicle weight can result in a 6%-8% fuel economy improvement. Replacing cast iron and traditional steel components with lightweight materials such as high-strength steel, magnesium (Mg) alloys, aluminum (Al) alloys, carbon fiber, and polymer composites can directly reduce the weight of a vehicle’s body and chassis by up to 50 percent and therefore reduce a vehicle’s fuel consumption.
One of the progresses in advanced materials is in lightweight and composite materials. These materials provide significant strength but at much lower weights than the currently used materials in cars. While some of these lightweight materials are already used in cars, one can see more such advanced materials making their way into cars, replacing significant amount of metal and thus increasing the mileage and overall fuel efficiency.
By using lightweight structural materials, cars can carry additional advanced emission control systems, safety devices, and integrated electronic systems without increasing the overall weight of the vehicle. For an electric vehicle, this will mean carrying extra batteries without increasing the overall weight.
So, what advances in this context can we expect in the short and long term?
In the short term, replacing heavy steel components with materials such as high-strength steel, aluminum, or glass fiber-reinforced polymer composites can decrease component weight by 10-60 percent.
In the longer term, advanced materials such as magnesium and carbon fiber reinforced composites could reduce the weight of some components by 50-75 percent.