CHAPTER 6 Fuels and Combustion

Fuels for mobile vehicles must have certain characteristics if the vehicles are to operate successfully. The fuels must have a high energy value so that a sufficient supply of energy can be stored in a reasonably small space on the vehicle. The fuels must vaporize and ignite easily in the engine, yet they must be reasonably safe to handle. Nearly all engine fuels today are derived from petroleum. World petroleum reserves are diminishing, but larger quantities of tar sands, shale oil, and coal remain in the earth. After suitable processing and refining, these latter fuels will have properties similar to petroleum. Eventually, however, all fossil fuels will be depleted, and alcohol and other renewable fuels may come into widespread use.