TODAY, WE SEE A WORLDWIDE resurgence in the popularity of ethanol, or ethyl alcohol, as a transportation fuel. The use of fuel ethanol in the U.S. can be traced back to the turn of the last century when Henry Ford built his first automobile, the quadricycle, to run on pure ethanol. Ford’s Model T’s were the first flexible fuel vehicles that could run on ethanol, gasoline, or a combination of both. World War I drove up ethanol demand to 50-60 million gallons per year. Demand continued to climb until the end of World War II when the reduced need for war materials and the low price of fossil fuel caused a drastic reduction in ethanol use as a fuel. From the late 1940’s until the late 1970’s, virtually no commercial fuel ethanol was available in the U.S. Between 1980 and 1991, less than 1 billion gallons of ethanol were produced annually in the United States. In 2006, the U.S. ethanol industry produced a record 4.9 billion gallons of fuel ethanol.
Due to its abundance and price, corn is the main feedstock used for ethanol production in the United States. Brazil, which blazed the trail for ethanol-powered vehicles, uses sugarcane juice as their primary feedstock for ethanol production.
Ethanol in the U.S. is most commonly produced in a dry mill where the corn is ground and converted into sugars which are then fermented into alcohol. According to the Renewable Fuels Association (RFA), the national trade association for the United States ethanol industry, as of January 1, 2007, there were 110 ethanol plants in the U.S. with a combined production capacity of over 5.4 billion gallons of ethanol per year. There were 73 ethanol refineries and 8 expansions under construction that are anticipated to add over 6 billion gallons of new annual production capacity by 2009.
While the growth in the production of ethanol from corn is expected to grow substantially from its current levels, recent studies suggest that ethanol produced from corn grown in the U.S. would realistically be able to provide only a small proportion, 12 – 15 BGY or about 10%, of total gasoline demand. Other studies and news articles suggest that, well before this level of production could be achieved, the price of corn would begin to negatively impact the costs of animal feed and food based on corn.
What is the solution to our need for more abundant, renewable feedstocks for ethanol production? Cellulosic biomass — the most abundant source of sugars on earth
