Listed below are all documents and RMI.org site pages related to this topic.
Transportation - Fossil fuel reduction opportunities - automotive design 23 Items
This chart shows why less than 0.5% of the energy in a typical modern auto’s fuel actually moves the driver, and only 5–6% moves the auto. An auto's weight is responsible for more than two-thirds of the energy needed to move it. All told, 86% of the fuel energy never reaches the wheels.
Lightweight autos needn’t cost more. The MY 2010 U.S. new-car fleet shows little or no correlation between lighter weight and higher prices.
Autos in the U.S. have increased in weight by 16% since 1986 to an average of 3,533 lb. in 2009. Cars have also gotten denser, rising 14%—from 28 to 32 lb per interior cubic foot. Yet since 1986, U.S. adults got only 8% heavier.
Powertrain efficiency from tank to wheels can't exceed 1.0, and is around 0.17 in a typical modern car or 0.35 in a good "full hybrid," but the energy needed to move the car can be reduced severalfold by making it lighter and more slippery.
Each 10% decrease in an auto’s aerodynamic drag can raise its fuel economy by very roughly 3%.
As with lightweight autos, more aerodynamic autos needn’t cost more. A survey of currently available autos shows that lower drag vehicles, as a whole, cost no more than less aerodynamic ones.
Every 10% decrease in an auto’s weight can raise fuel economy by roughly 6%.
It costs little or no more to purchase tires with dramatically improved rolling resistance. Going from the least to most efficient tires improves fuel economy by over 8%.
Our Revolutionary auto class is based on RMI’s extensive work on the Hypercar. We use a cost model for superefficient battery-electric and fuel cell autos for both cars and light trucks. These vehicles, described in this table, are designed to compete with EIA’s average automobile in price and all driver attributes.
Carbon fiber material supply is currently increasing by 9–10 million pounds per year. Demand began a 10-fold increase with Boeing’s and Airbus’s new carbon-intensive airplane orders in 2005.