Hope you're having fun overseas.
Below is something interesting along these lines that I happened to
catch in science news recently.
Todd S. Greene
###### Glenn Morton, 7/28/01 9:58 AM ######
> I put a small piece on my web page about what happens to a modern
> agricultural system when the oil is cut off. North Korea is a
> perfect example. Cuba would be also, but I don't have much data on
> them. It is at
FOR RELEASE: Aug. 6, 2001
Ethanol fuel from corn faulted as 'unsustainable subsidized food
burning' in analysis by Cornell scientist
Contact: Roger Segelken
ITHACA, N.Y. -- Neither increases in government subsidies to corn-based
ethanol fuel nor hikes in the price of petroleum can overcome what one
Cornell University agricultural scientist calls a fundamental input-
yield problem: It takes more energy to make ethanol from grain than the
combustion of ethanol produces.
At a time when ethanol-gasoline mixtures (gasohol) are touted as the
American answer to fossil fuel shortages by corn producers, food
processors and some lawmakers, Cornell's David Pimentel takes a longer
"Abusing our precious croplands to grow corn for an energy-inefficient
process that yields low-grade automobile fuel amounts to unsustainable,
subsidized food burning," says the Cornell professor in the College of
Agriculture and Life Sciences. Pimentel, who chaired a U.S. Department
of Energy panel that investigated the energetics, economics and
environmental aspects of ethanol production several years ago,
subsequently conducted a detailed analysis of the corn-to-car fuel
process. His findings will be published in September, 2001 in the
forthcoming Encyclopedia of Physical Sciences and Technology .
Among his findings are:
o An acre of U.S. corn yields about 7,110 pounds of corn for processing
into 328 gallons of ethanol. But planting, growing and harvesting that
much corn requires about 1,000 gallons of fossil fuels and costs $347
per acre, according to Pimentel's analysis. Thus, even before corn is
converted to ethanol, the feedstock costs $1.05 per gallon of ethanol.
o The energy economics get worse at the processing plants, where the
grain is crushed and fermented. As many as three distillation steps are
needed to separate the 8 percent ethanol from the 92 percent water.
Additional treatment and energy are required to produce the 99.8 percent
pure ethanol for mixing with gasoline. o Adding up the energy costs of
corn production and its conversion to ethanol, 131,000 BTUs are needed
to make 1 gallon of ethanol. One gallon of ethanol has an energy value
of only 77,000 BTU. "Put another way," Pimentel says, "about 70 percent
more energy is required to produce ethanol than the energy that actually
is in ethanol. Every time you make 1 gallon of ethanol, there is a net
energy loss of 54,000 BTU."
o Ethanol from corn costs about $1.74 per gallon to produce, compared
with about 95 cents to produce a gallon of gasoline. "That helps explain
why fossil fuels -- not ethanol -- are used to produce ethanol,"
Pimentel says. "The growers and processors can't afford to burn ethanol
to make ethanol. U.S. drivers couldn't afford it, either, if it weren't
for government subsidies to artificially lower the price."
o Most economic analyses of corn-to-ethanol production overlook the
costs of environmental damages, which Pimentel says should add another
23 cents per gallon. "Corn production in the U.S. erodes soil about 12
times faster than the soil can be reformed, and irrigating corn mines
groundwater 25 percent faster than the natural recharge rate of ground
water. The environmental system in which corn is being produced is being
rapidly degraded. Corn should not be considered a renewable resource for
ethanol energy production, especially when human food is being converted
o The approximately $1 billion a year in current federal and state
subsidies (mainly to large corporations) for ethanol production are not
the only costs to consumers, the Cornell scientist observes. Subsidized
corn results in higher prices for meat, milk and eggs because about 70
percent of corn grain is fed to livestock and poultry in the United
States Increasing ethanol production would further inflate corn prices,
Pimentel says, noting: "In addition to paying tax dollars for ethanol
subsidies, consumers would be paying significantly higher food prices in
Nickels and dimes aside, some drivers still would rather see their cars
fueled by farms in the Midwest than by oil wells in the Middle East,
Pimentel acknowledges, so he calculated the amount of corn needed to
power an automobile:
o The average U.S. automobile, traveling 10,000 miles a year on pure
ethanol (not a gasoline-ethanol mix) would need about 852 gallons of the
corn-based fuel. This would take 11 acres to grow, based on net ethanol
production. This is the same amount of cropland required to feed seven
o If all the automobiles in the United States were fueled with 100
percent ethanol, a total of about 97 percent of U.S. land area would be
needed to grow the corn feedstock. Corn would cover nearly the total
land area of the United States.
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