POSTED 8 FEBRUARY 2007
Alcohol: Cool solution to global warming?
Last week, the United Nation's Intergovernmental Panel on Climate Charge reported that the link between rising temperatures and carbon dioxide in the atmosphere is stronger than ever. Most of the greenhouse gases come from fossil fuels, so warming will intensify as more people in China, India and elsewhere enjoy the joys of joy-riding in private cars.
Photo: US Dept. of Energy
In the long run, we will all be dead. But in the short run, we hope humanity can mount an effective response to the warming that has been gathering speed since about 1980.
In countries like the United States that guzzle gasoline like there is no tomorrow, conservation may be the most sensible place to start reducing carbon dioxide. But the Bush Administration is also interested in shifting gasoline production from petroleum to biomass.
They propose to do what whiskey-makers have done for centuries -- ferment corn and distill the product into a liquid fuel. Only the ethyl alcohol won't be called "white lighting," "moonshine," or even "Old Kentucky." It will be called "ethanol," and it will be poured into the gas tank, not down the gullet.
Trenberth, National Center for Atmospheric Research
Let them [cars] drink ethanol
From a global warming standpoint, ethanol, biodiesel and other "biofuels" made from vegetation seem too good to be true: The crops absorb solar energy, are fermented into alcohol and then burned. Then the next biofuel crop pulls all the carbon dioxide they created out of the atmosphere.
Drive all you want, and you don't add any net carbon to the atmosphere. All driving, no warming, in other words.
It's quite a selling point, and the move to ethanol is well under way, spurred in part by a $0.51 per gallon U.S. subsidy. In 2005, 3.9 billion gallons of ethanol were blended into gasoline in the United States; comprising about 2 percent of gasoline sales by volume. The feds estimate 2006 production at more than 4.6 billion gallons. Brazil is making massive amounts of ethanol from sugar cane, and expects to start exports soon.
Most ethanol is blended as a 10 percent additive to gasoline, called E-10. Although many new cars can also indulge in E-85 (85 percent pure ethanol) this stuff is not widely sold at present.
Ethanol contains less energy than the same volume of gasoline, but it also makes less carbon monoxide and other pollution, and is a good, non-toxic additive for cold weather. But as the giant gasoline industry swerves off Petroleum Place and onto Ethanol Avenue, will the result be good -- or too good to be true?
Calling a fuel "renewable" does not automatically make it green. Skeptical? The European Union decided to promote biofuel to counter global warming, and in response nations in Southeast Asia clearcut rain-forests for palm trees that will make palm oil for fuel. Many of the plantations were built on highly organic soil, and when the farmers burned the land to clear it, they dumped millions of tons of carbon dioxide into the atmosphere. A biofuel scheme designed to slow global warming actually wound up accelerating warming (see #1 in the bibliography).
So before you convert grandpa's backwoods still into a weapon against climate change, you might want to ask some questions: How much net energy do we get from moonshine motorfuel? What is the global warming impact of the ethanol industry?
And will fermenting mountains of corn affect our food supply?
Let them eat ... gasoline?
The United States burns about 9 million barrels (1.4 billion liters) of gasoline each day, so we'll have to ferment a big heap of corn to slow global warming. One harbinger of the effect this will have on the food supply appeared last month. The San Francisco Chronicle quoted Peter Navarro, a business professor at University of California at Irvine, on the subject of tortillas in Mexico: "The price of oil is driving up the price of corn (because of increased ethanol production), which is driving up the price of tortillas."
More food shortages loom, according to Lester Brown of the Earth Policy Institute. Brown claims that a recent report from the U.S. Department of Agriculture drastically underestimated the biofuel demand for corn. Brown calculated that the ethanol plants in operation, under construction, or being planned will devour "139 million tons, half the 2008 harvest projected by USDA," in the 12 months starting September 1, 2008.
© David Tenenbaum
That mountain of corn -- half the giant American crop -- would "yield nearly 15 billion gallons of ethanol, satisfying 6 percent of U.S. auto fuel needs," Brown continued (ethanol now supplies about 2 percent).
The numbers seem solid. The ethanol industry's Renewable Fuels Association says 11.8 billion gallons are on line or under construction. That's about 20 percent below Brown's figure, but the association did not count facilities in the planning stage.
If the current subsidy for ethanol remains, 15 billion gallons of motoring moonshine will cost the U.S. Treasury $7.5 billion. More important, as Brown notes, grain prices will inevitably rise. "This unprecedented diversion of the world's leading grain crop to the production of fuel will affect food prices everywhere. As the world corn price rises, so too do those of wheat and rice, both because of consumer substitution among grains and because the crops compete for land."
Indeed, in early February, the price of corn reached $3.23 per bushel in the United States, a 50 percent rise in a year, and reserves were at their lowest in 10 years.
Maybe we should ask: Exactly how much net energy will corn ethanol provide?
Megan Anderson, project assistant; Terry Devitt, editor; S.V. Medaris, designer/illustrator; David Tenenbaum, feature writer; Amy Toburen, content development executive