Flexible fuel is also known as E-85 fuel. The E-85 is a blend of 85 percent methanol and 15 percent gasoline. The inclusion of gasoline in the mixture adds a lubricant into the fuel that prevents the deterioration of rubber components in the fuel system as well as corrosion in the metal components. Alcohol or methanol used in flexible fuel produces fewer greenhouse gases and harmful emissions than gasoline alone, therefore the E-85 is viewed as a cleaner solution to powering automobiles. New vehicles equipped to operate on the flexible fuel typically have green colored fuel caps and special badges to identify the popular option.
In most areas of the United States, flexible fuel is less expensive than regular unleaded gasoline, which makes the choice to use the fuel a viable one. The downside to this decision lies in the fact that a vehicle will burn more flexible fuel to travel the same distance regular gasoline will take the vehicle. This equates to the relatively equal cost and often higher cost to use flexible fuel instead of gasoline. This typically is not a great concern for those who wish to use a cleaner burning fuel; for those drivers wishing only to save on the fuel expense, however, it is often not a popular choice.
Flexible fuel cannot be used in a vehicle that is not specifically designed to burn the ethanol mixture. This is due, in part, to the requirement of the fuel system to provide more of the E-85 than it is designed to provide with gasoline. Perhaps the greatest reason the fuel is harmful to non-flexible fuel vehicles is the tendency for the methanol to break down the rubber components. The fuel will render the fuel system of non-equipped vehicles inoperable in a very short time. The vehicle's onboard computer must also be programmed to alter the engine's ignition timing to coincide with the use of the flexible fuel.
Cleaning the air and slowing the rate at which the greenhouse gases are released into the atmosphere is the goal of alternative fuels for vehicles. By lowering tail pipe emissions and providing a choice for consumers, the automobile manufacturers are beginning to take a proactive stance against pollution. Having more providers of the fuel is the next obstacle that must be overcome. The availability factor may hinder consumers from embracing flex fuel vehicles because gas stations that offer flex fuel are not plentiful in most areas.