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A Kinder, Gentler Crop?
These environmental concerns have led researchers like Heggenstaller to join a wave of interest in a new generation of biofuels, the much-hyped but yet-to-be-seen-on-the-market cellulosic ethanol. Cellulosic differs from grain ethanol in that the fuel comes from the fiber in the plant, rather than the starches in the grain. Any type of plant material can be a source of cellulose, and even cow manure could be processed into fuel.
Fans of cellulosic ethanol are interested in perennial grasses like prairie native switchgrass and towering miscanthus, which require much lower quantities of fertilizers and pesticides than corn and eliminate the need to plow fields annually, a major cause of soil erosion. They say these crops could produce much greater quantities of biomass than corn, and on lands less suitable for crop production.
Indeed, if biofuels are going to make a substantial dent in meeting our fuel needs, processors will need to look beyond corn. If all the corn currently grown in the U.S. were turned into ethanol, it would replace only 15 percent of our annual gasoline demand. (By way of comparison, we could eliminate 15 percent of our gasoline demand by increasing average fuel efficiency of U.S. cars by just four miles per gallon - an attainable goal using on-the-shelf technology.)
Due to soybeans' relatively low oil yield, soy biodiesel production in the U.S. has already been written off as marginal by most researchers. So many academic and industry leaders are intensely optimistic about the transition to cellulosic sources.
"There's no doubt cellulosic ethanol can supply our energy needs," says Emily Heaton, manager of Energy Crop Product Development at Ceres, Inc., a California-based plant biotechnology company that's working to develop high-yield biomass crops. She agrees with projections from the U.S. Department of Energy that say fuel from perennial grasses could replace more than a third of our petroleum needs by 2030. "We'll be producing more than a billion tons of biomass a year in an environmentally sustainable way," Heaton says.
But even the advent of cellulosic ethanol - which is not expected to come on line for at least several more years - could mean more corn, according to Charles Brummer, a professor of plant breeding at the University of Georgia who works with switchgrass and other perennial biomass plants. Corn stalks and other residues from the corn harvest could be used to make cellulosic ethanol just as readily as switchgrass.
"Farmers will produce what makes money," Brummer says. "As long as farm programs support corn production, we're not going to see them growing much of anything else."
Meanwhile, in the Rest of the World
The hype over biofuels in the U.S. and Europe has had wide-ranging effects perhaps not envisioned by the environmental advocates who promote their use. Throughout tropical countries like Indonesia, Malaysia, Brazil, and Colombia, rainforests and grasslands are being cleared for soybean and oil-palm plantations to make biodiesel, a product that is then marketed halfway across the world as a "green" fuel.
In Southeast Asia, and increasingly in the Amazon, plantations of the African oil palm have become wildly lucrative. After monocropping the palms on recently cleared rainforest land, growers press the palm fruit and kernel for oil that can be used in both food and industrial applications, including - and increasingly - as biodiesel.
The palm oil industry is booming: global exports increased more than 50 percent from 1999 to 2004. To meet the growing demand, producers in Malaysia and Indonesia have ramped up production by clearing thousands of square miles of rainforest for new plantations.
In Indonesia, rainforest loss for oil palms has contributed to the endangerment of 140 species of land animals, while in Malaysia animals like the Sumatran tiger and Bornean orangutan have been pushed to the brink of extinction. Fish kills have become common in waterways surrounding plantations and palm-oil mills, as soil erosion from the cleared land and mill effluents have left waterways clogged with sediment and unviable.
The boom hasn't been limited to Southeast Asia. In one of the most disturbing examples of the biofuel hype's hidden effects, right-wing paramilitary groups in Colombia - a country mired in a four-decade-old civil war - have in recent years begun plant
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