Production
To understand how ethanol is produced, we will describe a simplified
description fats and oils. of this technical chemical process. Essentially, ethanol
is the byproduct a small organism called yeast which consumes simple sugars.
This process if yeast consuming sugar is called fermentation and can be
represented by the following chemical equation:
The source of this sugar is typically the starch found in grains and other plant
matter such corn. Once sugar has been fermented into ethanol, it is then
concentrated into a more potent form through a process of evaporation and
condensation called distillation [FUNK 1]. A supplemental step that is required if
ethanol is to be blended with gasoline, is the dehydration of the distillate, which
removes any remaining water from the distilled ethanol [WIKI ethanol fuel].
Ethanol can be produced from a variety of plants including corn, rye straw,
wood pulp, and sugarcane. Domestically, the energy crop of choice is corn.
However, sugarcane is the crop used in Brazil to produce ethanol [Consumer
18]. Globally there were about 11.1 billion gallons of ethanol produced annually.
Of all the ethanol produced in the world, 39% of it is made in Brazil where
ethanol powered vehicles dominate auto markets [WIKI ethanol fuel]. Due to the
recent 2005 energy policy act, ethanol use is on the rise in the United States.
The act provides for new tax incentives for those who produce and distribute
ethanol fuel. President Bush hopes that ethanol will "replace more than 75% of
our oil imports from the Middle East by 2025.[Healey 1]." As a result, it is
estimated that 4.8 billion gallons of ethanol will be produced by the United States
in 2006. In the U.S., nearly 100 plants produce ethanol in 21 states [US DOE ~
Biomass]. Further, 33 more plants are being built to expand current output
[Chandrashekhar 1]. Looking to the future, the U.S Senate passed legislation in
2006 that will double our ethanol output by the year 2010[CBS 1].
Additionally, research is being done to develop a
new kind of fuel called cellulosic ethanol. This kind of
ethanol is theoretically derived from switch grass and
other agricultural wastes instead of corn.
Subsequently, cellulosic ethanol reduces CO2
emissions because it can be produced more
efficiently than ethanol from corn. However, it is still
uncertain if it is even possible to create this kind of fuel [Barrionuevo 1].
