A large part of the alternative fuels boom has been a part of civilization for thousands of years: ethanol. The same substance that makes alcoholic beverages intoxicating is also a useful fuel. Ethanol’s potential as a motor fuel has been known since the first internal combustion engines were made; The Ford Model T was able to run on gasoline, ethanol or any mix of the two (Bettelheim 802).
As the use of automobiles grew from the 1900's to the 1920's, it was found that petroleum was a cheaper fuel source than ethanol (Bettelheim 802). Ethanol was mixed with gasoline to improve the fuel's octane rating until the 1920's, when oil companies stopped using it because fear of being labeled as bootleggers. Ethanol had a brief resurgence during World War II, after which it was not used as fuel until the 1970's, when the OPEC oil embargoes highlighted the need for alternatives to imported oil (805). This was the driving factor in the development of ethanol as an alternative to gasoline.
The use of ethanol has greatly increased due to the banning of toxic additives to gasoline. Lead improved the octane rating of gasoline, but its use as an additive was banned due to its toxicity (Runge 1). Another chemical that improves the burning of gasoline is MTBE. It has been banned in many areas of the US over the past five years and ethanol is now used instead (Yacobucci 7).
While the banning of MTBE and lead has been one driving force of the growing demand for ethanol since the 1970's, a piece of legislation that was implemented in 2005 is set to drive demand even higher. The Clean Air Act of 2005 set a yearly minimum amount of ethanol that must be blended with gasoline in the US, called the Renewable Fuel Standard (Yacobucci 18). President Bush expanded this act in 2007 with the Energy Independence and Security Act of 2007, raising the yearly minimums even higher. The 2007 Energy Act also adds a requirement that a portion of the RFS is met with biofuels other than ethanol from corn starch. The amount mandated for 2006 is four billion gallons of corn ethanol, and this will gradually expand to thirty-six billion gallons in 2022, of which twenty-one billion gallons must be from sources other than corn starch (19). To provide a basis for comparison, in 2004 about 136 billion gallons of gasoline were consumed in the US and about two billion gallons of ethanol (Yacobucci 8).
Ethanol is mainly consumed in two forms in the US. Most ethanol sold in the US is in a mix of 10% ethanol and 90% gasoline called E10 (Yacobucci 8). Any car is able to run on this, and it is currently being sold in much of the country. The ethanol works as an additive to help the gasoline burn more cleanly, improves performance, and provides energy as a fuel. The other less common form is E85, which contains 85% ethanol and 15% gasoline. Modern cars must be specially designed to run on E85. Many newer models of cars are designed as such, and these are called flex-fuel...