What
is Ethanol?
Ethanol is an alcohol fuel made by fermenting the sugars
found in grains, such as corn and wheat, as well as
potato wastes, cheese whey, corn fiber, rice straw,
sawdust, urban wastes, and yard clippings. There are
several processes that can produce alcohol (ethanol) from
the various plant forms of biomass. The two most commonly
use processes involve using yeast to ferment the sugars
and starch in the feed stock (corn or wheat) to create
ethanol. This is how wine, beer, and liquor is made.
Cider, for example, is made by fermenting apple juice.
A new process uses enzymes to break down the cellulose in
woody fibers, so that more of the plant waste can be used
to make ethanol. This new technology will soon make it
possible to make ethanol from trees, grasses, and crop
residues. Trees and grasses require less energy to
produce then corn, which must be replanted and tended
every year. Scientists have developed fast-growing,
hybrid trees that can be harvested in ten years of less.
Many perennial grasses can be established in one year and
can produce two harvests a year for many years. These new
energy crops will not require constant tending or
fertilizers and their root systems will rebuild the soil.
They will also prevent erosion and offer habitats for
wild animals.
Soon, you may find yourself driving by huge farms that
are not producing food or animal feed, but fuel for
ethanol and power plants. These energy crops will be a
boon to the American farmer. In recent years, the
advances in farming have allowed farmers to produce
enough food for the country on much less land. In fact,
American farmers export forty percent of the food they
grow, and still have plenty of land that is not under
production. Energy crops will allow farmers to use more
of their land productively.
History of Ethanol
Ethanol is not a new product. In the 1850s, nearly 90
million gallons were produced every year. At the
beginning of the Civil War, a $2.08 per gallon tax was
imposed on liquor to finance the war. Since ethanol is a
product of fermentation, it was taxed as liquor. At the
same time, competitors such as kerosene and methanol were
taxed at only 10 cents a gallon. As a result, ethanol
could not compete as a fuel, and disappeared from the
market.
In 1906, the federal liquor tax was repealed and ethanol
became competitive as a fuel. In 1908, Henry Ford
designed his Model T Ford to run on a mixture of gasoline
and alcohol, calling it the fuel of the future. During
World War I, the use of ethanol increased rapidly and, by
the end of the war, production had risen to 50 million
gallons a year. It was used not only as a fuel, but in
the manufacture of war materials, as well.
In 1919, the ethanol industry received another blow when
the era of Prohibition began. Since ethanol was
considered liquor, it could only be sold when poisons
were added to make it undrinkable. In a process called
denaturing, ethanol was rendered poisonous by the
addition of 3-5% petroleum components.
By the 1920s, ethanol was no longer thought of as an
alternative to gasoline; it was considered a gasoline
extender or octane enhancer that boosts the power of the
car's engine. However, with the production of ethanol
effectively banned by Prohibition, other products were
used for that purpose.
With the end of Prohibition in 1933, interest in the use
of ethanol as a fuel was revived. During World War II,
production of ethanol rose dramatically, to 600 million
gallons a year. While some ethanol was used as fuel, most
of it was used in the production of synthetic rubber,
since supplies of natural rubber had been cut off by the
war in Asia.
After the war, ethanol production again declined sharply.
Not only were there no more government contracts to
produce ethanol, but farmers were exporting much of their
grain to foreign markets. At the same time, large
supplies of cheap foreign oil made gasoline less
expensive.
Ethanol Today
In the 1970s, embargoes by the major oil producing
countries curtailed gasoline supplies. With supplies of
gasoline reduced, long lines formed at gas pumps, and
prices for gasoline rose. The embargoes helped to revive
interest in ethanol as an alternative fuel.
In 1988, more than fifty ethanol plants, mostly in the
Midwest, produced over a billion gallons of ethanol. Many
new plants are planned or are under construction. Another
reason for the renewed interest in ethanol is the
environmental benefit. Since ethanol contains oxygen,
using it as fuel additive results in a cleaner burning
gasoline. Gasoline containing up to ten-percent ethanol
is widely used in urban areas across the country that
fail to meet public health standards for carbon monoxide
and ozone. These ethanol blends, called gasohol, result
in up to 25% fewer carbon monoxide emissions than
conventional gasoline. It costs more to produce ethanol
than gasoline, but federal and state tax advantages make
ethanol use competitive in the market place today. Using
ethanol can also reduce carbon dioxide emissions. Fossil
fuels release carbon into the air, where it reacts with
oxygen to form carbon dioxide, a greenhouse gas that
traps the earth's heat. Ethanol is made from crops, which
take in carbon dioxide and give off oxygen. This carbon
cycle maintains the balance of carbon dioxide in the
atmosphere.
As new technologies for producing ethanol from all parts
of a plant or tree become available, the production and
use of ethanol should increase dramatically.
|
Many farmers grow
nothing but wheat. Seen here is a gigantic wheat field.
Without wheat we would not be able to produce ethanol.
See across for a complete description of this process.
Ethanol first became popular as a fuel with the Model T
(seen above). Henry ford mixed ethanol with gasoline to
run this machine.
Without ethanol plants like this one, mass production of
this invaluable fuel would be impossible. |
