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"We pay a price to have it in a convenient form," Tiffany says. And that price is burning fossil fuels. If energy savings is your goal, you're off to a bad start if you burn nearly as much in fossil fuels as you gain in biofuels.
[ 2 ] It isn't easy being "green" when growing corn.
Corn hungers for high-nitrogen fertilizers. It thirsts for water, including from ancient aquifers. And it's addicted to chemicals. None of these conditions are good for the environment.
Corn requires heavy doses of fertilizer--an average of 135 pounds of nitrogen spread on every acre--as well as phosphorus and phosphate. Corn accounts for nearly half of the crop nutrient use in the nation; nothing else comes close. Corn also requires heavy applications of herbicides and insecticides; corn makes up approximately a quarter of the acres of crops planted in the United States but accounts for nearly two-thirds of total herbicide use.
Trouble is, these chemicals don't stay put. Excess nitrogen leaches into the groundwater, posing potentially fatal hazards to infants. Pesticides pollute nearby lakes and streams, killing fish such as smallmouth bass. Runoff of soil and phosphorus causes algae blooms in nearby lakes. Nitrogen and phosphorus from the Midwest Farm Belt flow down the Mississippi River, feeding algae growth and decomposition that create "hypoxia"--an oxygen-depleted "dead zone" roughly the size of New Jersey in the Gulf of Mexico.
[3] Corn crowds out wildlife.
During the last half-century, agricultural fields have become bigger, obliterating the wetlands and biodiverse landscape that once characterized rural areas. As all but the rockiest, steepest, or wettest land was cultivated, 99 percent of our native prairie disappeared and all but a fraction of our original wetlands were drained. Many prairie species, especially birds, became rare or endangered. In Illinois, for example, seven species of grassland birds, including upland sandpipers, meadowlarks, and several species of sparrows, declined more than 90 percent between the late 1950s and the mid-1980s. Game species, such as ducks and pheasants, have also suffered.
In recent decades, the federal government has rented land from farmers across the United States, especially highly erodible land, through the Conservation Reserve Program (CRP). These set-aside acres are planted with native grasses and trees and slowly restored. Since the program began, CRP lands have showed impressive increases in grassland birds such as bobolink and dickcissel. In one study in Iowa, the number of pheasants increased 13-fold on CRP lands.
But as a burgeoning ethanol program boosts demand for corn, crop prices are predicted to rise. As they do, Tiffany says, farmers will be tempted to pull their acres out of CRP and put them back into production. In fact, the National Grain and Feed Association recently asked a U.S. House Agriculture Committee to alter CRP to free up more farmland to raise crops for a burgeoning biofuels industry.
Loss of CRP lands means a net loss for wildlife.
[ 4 ] Corn ethanol doesn't cut enough greenhouse gases.
Ethanol indeed reduces air pollution--in small doses. Ethanol has become a much-needed replacement for the gasoline additive MBTE (a possible carcinogen and pervasive groundwater pollutant) to help gasoline burn cleaner. Blending a small amount of ethanol with gasoline reduces carbon monoxide, volatile organic compounds, and particulates.
But when you look at the entire life-cycle of ethanol--from growing to harvest to processing to combustion--burning E85 (85 percent ethanol) as fuel actually produces more carbon monoxide, volatile organics, particulates, and oxides of sulfur and nitrogen than an energy-equivalent amount of gasoline, according to the University's study.
And ethanol doesn't do much to address the big issue: global warming. "We found corn ethanol as currently produced saves about 12 percent greenhouse gases from gasoline," Hill says. And that's if the corn is grown on existing fields. "If you take land out of CRP you may have a net greenhouse gas release." That would actually exacerbate global warming.
[ 5 ] We can't grow enough corn.
Twelve percent of the U.S. corn crop is converted to ethanol, which replaces less than 2 percent of U.S. gasoline usage. Diverting all our corn to ethanol production (which would mean no more corn flakes, marbled beef, fructose-sweetened soda, or any other corn product), would reduce gasoline consumption by only 12 percent.
But, according to Hill's study, even that dismal statistic is overly sanguine. Because so much fossil fuel is burned just
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