Home' Technology Review : January February 2008 Contents FEATURE STORY 45
corn ethanol] is just the straight-out economics and the costs.
The energy input/output is not very good."
The high energy requirements of ethanol production mean that
using ethanol as fuel isn't all that much better for the environment
than using gasoline. One might think that burning the biofuel
would release only the carbon dioxide that corn captures as it grows.
But that simplified picture, which has often been conjured up to
support the use of ethanol fuel, doesn't withstand closer scrutiny.
In fact, Polasky says, the fossil fuels needed to raise and harvest
corn and produce ethanol are responsible for significant carbon
emissions. Not only that, but the cultivation of corn also produces
two other potent greenhouse gases: nitric oxide and methane.
Polasky calculates that corn-derived ethanol is responsible for
greenhouse-gas emissions about 15 to 20 percent below those asso-
ciated with gasoline: "The bottom line is that you're getting a slight
saving in terms of greenhouse-gas emissions, but not much."
If corn-derived ethanol has had little impact on energy markets
and greenhouse-gas emissions, however, its production could have
repercussions throughout the agricultural markets. Not only are
corn prices up, but so are soybean prices, because farmers planted
fewer soybeans to make room for corn.
In the May/June 2007 issue of Foreign A airs, C. Ford Runge, a
professor of applied economics and law at Minnesota, cowrote an
article titled "How Biofuels Could Starve the Poor," which argued
that "the enormous volume of corn required by the ethanol indus-
try is sending shock waves through the food system." Six months
later, sitting in a large o ce from which he directs the university's
Center for International Food and Agricultural Policy, Runge
seems bemused by the criticism that his article received from local
politicians and those in the ethanol business. But he is steadfast in
his argument: "It is clearly the case that milk prices, bread prices,
are all rising at three times the average rate of increase of the last
10 years. It's appreciable, and it is beginning to be appreciated."
The recent OECD report, released in early September, is just
the latest confirmation of his warnings, says Runge. And because
a larger percentage of their income goes to food, he says, "this is
really going to hit poor people." Since the United States exports
about 20 percent of its corn, the poor in the rest of the world are
at particular risk. Runge cites the doubling in the price of tortillas
in Mexico a year ago.
All these factors argue against the promise of corn ethanol as
a solution to the energy problem. "My take," says Polasky, "is that
[ethanol] is only going to be a bit player in terms of energy sup-
plies." He calculates that even if all the corn planted in the United
States were used for ethanol, the biofuel would still displace only
12 percent of gasoline consumption. "If I'm doing this for energy
policy, I don't see the payback," he says. "If we're doing this as farm
support policy, there may be more merit there. But we're going to
have to go to the next generation of technology to have a signifi-
cant impact on the energy markets."
Since the oil crisis of the 1970s, when the price of a barrel of petro-
leum peaked, chemical and biological engineers have chased after
ways to turn the nation's vast reserves of "cellulosic" material such
as wood, agricultural residues, and perennial grasses into ethanol
and other biofuels. Last year, citing another of President Bush's
goals---reducing U.S. gasoline consumption by 20 percent in 10
years---the U.S. Department of Energy (DOE) announced up to
$385 million in funding for six "biorefinery" projects that will use
various technologies to produce ethanol from biomass ranging
from wood chips to switchgrass.
According to a 2005 report by the DOE and the U.S. Depart-
ment of Agriculture, the country has enough available forest and
agricultural land to produce 1.3 billion tons of biomass that could
go toward biofuels. Beyond providing a vast supply of cheap feed-
GOLD PILE A coproduct of
corn ethanol production is a valu-
able animal feed called distillers
dried grains. The high-protein
grains can be fed to dairy cows,
cattle, pigs, and poultry.
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