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Science Forum Index » Philosophy Forum » Ethanol Controversy...
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| turtoni... |
 Posted: Sat Jun 21, 2008 5:46 pm |
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"It is disputed whether ethanol as an automotive fuel results in a net
energy gain or loss. As reported in "The Energy Balance of Corn
Ethanol: an Update,"[43] the energy returned on energy invested
(EROEI) for ethanol made from corn in the U.S. is 1.34 (it yields 34%
more energy than it takes to produce it). Input energy includes
natural gas based fertilizers, farm equipment, transformation from
corn or other materials, and transportation. However, other
researchers report that the production of ethanol consumes more energy
than it yields.[44][45] In comparison, sugar cane ethanol EROEI is at
around 8 (it yields 8 joules for each joule used to produce it).
[citation needed] Recent research suggests that cellulosic crops such
as switchgrass provide a much better net energy production than corn,
producing over five times as much energy as the total used to produce
the crop and convert it to fuel.[46] If this research is confirmed,
cellulosic crops will most likely displace corn as the main fuel crop
for producing bioethanol.
Michael Grunwald reports that one person could be fed 365 days "on the
corn needed to fill an ethanol-fueled SUV".[47] He further reports
that though "hyped as an eco-friendly fuel, ethanol increases global
warming, destroys forests and inflates food prices."
Environmentalists, livestock farmers, and opponents of subsidies say
that increased ethanol production won't meet energy goals and may
damage the environment, while at the same time causing worldwide food
prices to soar. Some of the controversial subsidies in the past have
included more than $10 billion to Archer-Daniels-Midland since 1980.
[48][neutrality disputed] Critics also speculate that as ethanol is
more widely used, changing irrigation practices could greatly increase
pressure on water resources. In October 2007, 28 environmental groups
decried the Renewable Fuels Standard (RFS), a legislative effort
intended to increase ethanol production, and said that the measure
will "lead to substantial environmental damage and a system of
biofuels production that will not benefit family farmers...will not
promote sustainable agriculture and will not mitigate global climate
change."[49][50]
Recent articles have also blamed subsidized ethanol production for the
nearly 200% increase in milk prices since 2004,[51] although that is
disputed by some[citation needed]. Ethanol production uses the starch
portion of corn, but the leftover protein can be used to create a high-
nutrient, low-cost animal feed.[52]
In 2007 the United Nations' independent expert on the right to food,
called for a five-year moratorium on biofuel production from food
crops, to allow time for development of non-food sources. He called
recent increases in food costs because of fuel production, such as the
quadrupling of world corn price in one year, a growing "catastrophe"
for the poor.[53] In February 2007, riots occurred in Mexico because
of the skyrocketing price of tortillas. Ethanol has been credited as
the reason for this increase in food prices [1]. The demand for corn
has had a rippling effect on many corn-based products, like tortillas.
The effects of ethanol and the increasing cost of food have also been
felt in Pakistan, Indonesia, and Egypt [2].
Oil has historically had a much higher EROEI than corn produced
ethanol, according to some[citation needed]. However, oil must be
refined into gasoline before it can be used for automobile fuel.
Refining, as well as exploration and drilling, consumes energy. The
difference between the energy in the fuel (output energy) and the
energy needed to produce it (input energy) is often expressed as a
percent of the input energy and called net energy gain (or loss).
Several studies released in 2002 estimated that the net energy gain
for corn ethanol is between 21 and 34 percent. The net energy loss for
MTBE is about 33 percent. When added to gasoline, ethanol can replace
MTBE as an anti-knock agent without poisoning drinking water as MTBE
does. In Brazil, where the broadest and longest ethanol producing
experiment took place, improvements in agricultural practices and
ethanol production improvements led to an increase in ethanol net
energy gain from 300% to over 800% in recent years.[citation needed]
Consuming known oil reserves is increasing oil exploration and
drilling energy consumption which is reducing oil EROEI (and energy
balance) further.[54]
Opponents claim that corn ethanol production does not result in a net
energy gain or that the consequences of large scale ethanol production
to the food industry and environment offset any potential gains from
ethanol. It has been estimated that "if every bushel of U.S. corn,
wheat, rice and soybean were used to produce ethanol, it would only
cover about 4% of U.S. energy needs on a net basis."[55] Many of the
issues raised could likely be fixed by techniques now in development
that produce ethanol from agricultural waste, such as paper waste,
switchgrass, and other materials, but EIA Forecasts Significant
Shortfall in Cellulosic Biofuel Production Compared to Target Set by
Renewable Fuel Standard.[56]
Proponents cite the potential gains to the U.S. economy both from
domestic fuel production and increased demand for corn. Optimistic
calculations project that the United States is capable of producing
enough ethanol to completely replace gasoline consumption.[citation
needed] In comparison, Brazil's ethanol consumption today covers more
than 50% of all energy used by vehicles in that country.
In the United States, preferential regulatory and tax treatment of
ethanol automotive fuels introduces complexities beyond its energy
economics alone. North American automakers have in 2006 and 2007
promoted a blend of 85% ethanol and 15% gasoline, marketed as E85, and
their flex-fuel vehicles, e.g. GM's "Live Green, Go Yellow" campaign.
[57] The apparent motivation is the nature of U.S. Corporate Average
Fuel Economy (CAFE) standards, which give an effective 54% fuel
efficiency bonus to vehicles capable of running on 85% alcohol blends
over vehicles not adapted to run on 85% alcohol blends.[58] In
addition to this auto manufacturer-driven impetus for 85% alcohol
blends, the United States Environmental Protection Agency had
authority to mandate that minimum proportions of oxygenates be added
to automotive gasoline on regional and seasonal bases from 1992 until
2006 in an attempt to reduce air pollution, in particular ground-level
ozone and smog.[59] In the United States, incidents of methyl
tert(iary)-butyl ether (MTBE) groundwater contamination have been
recorded in the majority of the 50 states,[60] and the State of
California's ban on the use of MTBE as a gasoline additive has further
driven the more widespread use of ethanol as the most common fuel
oxygenate.[61]
A February 7, 2008 Associated Press article stated, "The widespread
use of ethanol from corn could result in nearly twice the greenhouse
gas emissions as the gasoline it would replace because of expected
land-use changes, researchers concluded Thursday. The study challenges
the rush to biofuels as a response to global warming."[62]
One acre of land can yield about 7,110 pounds (3,225 kg) of corn,
which can be processed into 328 gallons (1240.61 liters) of ethanol.
That is about 26.1 pounds (11.84 kg) of corn per gallon.
http://en.wikipedia.org/wiki/Ethanol#Controversy |
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| Immortalist... |
| Posted: Sun Jun 22, 2008 6:16 pm |
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On Jun 21, 10:38 pm, turtoni <turt... at (no spam) fastmail.net> wrote:
Quote: On Jun 22, 1:23 am, Immortalist <reanimater_2... at (no spam) yahoo.com> wrote:
On Jun 21, 8:46 pm, turtoni <turt... at (no spam) fastmail.net> wrote:
"It is disputed whether ethanol as an automotive fuel results in a net
energy gain or loss.
http://en.wikipedia.org/wiki/Ethanol#Controversy
Land ready for growing food is finite.
Energy companies want to use this land to grow plants for fuel.
Any plants will make fuel.
Many plants grow where food cannot grow.
Increasing the amount of plants increases the oxygen in the
atmosphere.
Market forces could create to much good air.
What to do? It is good to see the debate begin to widen and show how
this could change everything around, quick as the market can.
huh?
http://youtube.com/watch?v=weKJjknf748
good one!
http://youtube.com/watch?v=uJrOVLEUBgw
http://youtube.com/watch?v=eSnS0ab1KP0 |
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