In this regard, interest in alternative fuel sources is constantly increasing as oil prices are also increasing. It is a fact that nearly all of America's transportation sector depends on oil. Since oil is not renewable, available oil sources should not be used entirely for transportation. Oil is still used to provide energy in the country and other areas that need oil. Therefore, before oil runs out completely, cars that do not rely on oil should be produced (U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, n.d.). These cars will not only help conserve dwindling oil supplies, but will also help protect the environment from carbon dioxide pollution and other harmful emissions. Some of the automakers responsible for producing some of these hybrid vehicles are Mazda, Mercury, Lexus, Ford, Chevrolet, Saturn, just to name a few