Approximately half of all petroleum refined is used for motor vehicles and their infrastructure.
Motor vehicles are an integral part of American life.
Trucks, vans, and other vehicles have become crucial for the delivery of goods and the personal automobile has enormously increased personal freedom, convenience, and mobility. There are now approximately 600 million motor vehicles worldwide, of which about 75 percent are personal automobiles. It is projected that there will an increase of 30 percent in the worldwide number of motor vehicles within the next decade. In response to the Clean Air Act of 1970 and concerns about oil prices and availability, automobile manufacturers instituted a number of engineering improvements in order to control emissions and increase fuel economy. These refinements include greater use of lightweight materials, development of emissions control technologies such as catalytic converters, and use of computer-sensing equipment to monitor engine performance.