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“Ethanol production using corn grain
required 29 percent more fossil energy than
the ethanol fuel produced,” reported
Patzek in the journal Natural Resources
Research last winter. He added that ethanol
produced from other common sources, such
as biomass (wood products and agricultural
waste), requires 50 percent or more fossil
fuel derived energy than the ethanol that
results can produce.
“People tend to think of ethanol and
see an endless cycle: Corn is used to produce
ethanol, ethanol is burned and gives off
carbon dioxide, and corn uses the carbon
dioxide as it grows,” says Patzek.
“But that isn’t the case. Fossil
fuel actually drives the whole cycle.”
Ethanol is primarily in use today as an
octane-boosting fuel additive, but it can
also be used as a primary fuel in some engines.
Most gasoline sold in North America today
contains about five percent ethanol, but
some vehicles--such as the Ford Explorer
and Chevy Silverado--can run on blends of
up to 85 percent ethanol. In order to stimulate
production, the U.S. offers generous tax-based
subsidies to farmers who grow crops for
ethanol.
While Patzek's evidence may be compelling,
his views on ethanol are not popular. Critics
point out that his findings are based on
farming and production practices that are
fast becoming obsolete, and that newer techniques
and machinery can make the ethanol production
process much more energy efficient.
Hosein Shapouri, an economist at the U.S.
Department of Agriculture, estimates that
ethanol fuel can actually generate 67 percent
more energy than it takes to produce it.
He points out that scientists are experimenting
with using alternative sources like solid
waste, grass and wood to make the ethanol
production process that much more energy
efficient.
While the jury may still be out as to whether
ethanol production can generate a positive
or negative “energy balance,”
there are also some potential hazards with
ethanol production. For instance, the nitrogen
fertilizer needed to grow corn and other
crops ends up in waterways, causing “algae
blooms” that can choke out other life
in affected areas. And while ethanol produces
fewer carbon monoxide emissions than regular
gasoline, it does contribute significantly
to low-lying smog.
Doubts about ethanol underscore a fundamental
problem in getting many types of renewable
energy sources, including hydrogen, into
mainstream usage: Until fuel sources like
solar or wind power can provide clean ways
to make clean fuel, the processes must rely
on coal, oil, gas and nuclear energy. Indeed,
while we may be able to see a clean energy
future, we are still wrangling with how
to get there.
CONTACTS:
U.S. Department of Energy Ethanol Facts,
www.eere.energy.gov/biomass/ethanol.html
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Dear EarthTalk:
How can I find information on toxic spills
and major polluters
in another part of the country where I am
considering moving?
—
Elizabeth Primiano, via e-mail
Passage of the Emergency Planning and Community
Right to Know Act in 1986 ensured that the
public could access information on “chemical
releases,” but did not provide a very
easy way to filter through data tucked away
in vast government databases. But the Internet
has now changed all that.
Today, the U.S. Environmental Protection
Agency (EPA) provides free access to such
data via the Envirofacts Data Warehouse
on its website. You can just plug in a zip
code to locate polluters, hazardous waste
sites and other relevant environmental data
in a specific region. Envirofacts incorporates
the federal Toxic Release Inventory (a database
of annual toxic spills and releases), lists
hazardous waste sites on the “Superfund”
list (those slated for cleanup), and tracks
violations of the Clean Water and Clean
Air acts.
Another good source for pollution information
is Scorecard, a website operated by the
non-profit advocacy group, Environmental
Defense. The free online service helps users
comb through more than 400 authoritative
scientific and governmental databases on
various forms of pollution to assess local
environmental quality. Additionally, the
site provides lists of toxic chemical releases
and provides links to online references
whenever available. Scorecard is regularly
updated so that users can be sure they are
getting the most current information.
The Right-to-Know Network (RTK NET), an
information retrieval service launched in
1989 that predates both Envirofacts and
Scorecard, provides access to numerous environmental
databases that can help you identify specific
factories and their environmental effects,
and assess the people and communities impacted.
A project of OMB Watch, a government watchdog
organization based in Washington, DC, the
service migrated to the Internet in the
mid-1990s, and its popularity waned as government
agencies began to provide data directly
to those who wanted it.
While RTK NET still provides up-to-date,
zip-code-based information on toxic releases,
its founders focus most of their attention
these days on advising organizations and
professionals who work on environmental,
health and safety issues. It recently merged
with the Working Group on Community Right-to-Know,
a clearinghouse for right-to-know laws and
information. The new organization now focuses
more on advocacy and seeks to “advance
the public’s right to know about environmental
and health threats [and] defend against
attacks on public access to environmental
and health information…”
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