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Food versus fuel, or can we have both?

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American



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Brazil grows a lot of sugar cane, and much of it they now turn into ethanol fuel. They make enough that biofuels"”also including diesel from soy"”now provide 45 percent of the fuel that powers Brazilian automobiles. Rufino Uribe (cc-by-sa-2.0) "In June more than 50 percent of fuels will be coming from agriculture in my country," former minister of agriculture Roberto Rodrigues said at the State of the Planet conference. That is a good thing, since ethanol from sugar cane delivers roughly nine times more energy as fuel than it takes to produce it (as compared with corn, which delivers less or only slightly more, depending on whose analysis you trust). But, according to the United Nations Food and Agriculture Organization (FAO), a growing world population will require 42 percent more production of grain and meat in the next two decades. And planting more sugarcane displaces other crops or pasture, which can then lead to more clearing of the Amazon rainforest, as a recent study in Science showed. Rodrigues argues that the food-versus-fuel debate is misleading. "Agriculture will be not only be providing food but everything to live," he said. "Some say production of biofuels will reduce production of food. This is not true. This is a lie." For instance, sugar cane fields must be rotated to other crops, such as soy, every five years, meaning that 20 percent of the land used to grow the sweet grass will be in actual food production in any given year. And sugarcane is not a staple food crop, which means using it to produce fuel won't directly affect food prices. If sugarcane does displace other food crops because of demand for fuel, as some studies have shown, then the rich will be filling their gas tanks as the poor starve. And Rodrigues made no promises about the ongoing deforestation in the Amazon in response to a question from the audience. But there is still one compelling argument in favor of ethanol: you can drink it. As Rodrigues notes, he has been doing so in the form of caipirinhas for years and his motor at the age of 65 is still running fine.