area used to grow corn to convert to ethanol was 5.1 million hectares, out of a total area for corn production of 29 million hectares and 144 million hectares globally.

Together, an area of 8 million hectares was devoted to ethanol production in Brazil and the United States. The total area used for agriculture in the world is about 1,300 million hectares, so less than 1 percent of this area is being used for ethanol production, Goldemberg pointed out. Similarly, the total amount of ethanol produced by Brazil and the United States in 2006 was about 36 billion liters, which is less than 1 percent of petroleum use.

“You sometimes wonder why people are concerned so much,” Goldemberg observed. However, there are several reasons for that concern, he added. Ethanol production in the United States and Brazil is slated to increase. In Brazil, production is expected to double by the year 2015. “That’s not an extrapolation,” Goldemberg said, “it’s a calculation based on the number of [ethanol] plants that have been licensed and are under construction.” In the United States, the 2007 Energy Independence and Security Act places an upper limit on corn-based ethanol of 56.8 billion liters per year by 2022, which is approximately a tripling from current levels. Furthermore, using more advanced cellulosic-based technologies, ethanol production in the United States could increase by at least another 80 billion liters per year by 2022, and in the European Union, where sugar beets are currently the crop used most often for ethanol, production could increase to 15 billion liters per year by 2020.

At that point, ethanol could replace 6 percent of the gasoline used in the world. Production at that level might enable the ethanol-producing companies to establish “a new OPEC of ethanol,” Goldemberg said. “Saudi Arabia controls 12 percent of the oil, but it has a tremendous weight on what happens in the world. So this is not an insignificant matter.”

Many countries have established mandates that call for particular levels of ethanol consumption in the future. Yet production costs vary greatly from country to country, from more than €50 per 1,000 liters for sugar beets in Germany to less than €15 per 1,000 liters for sugarcane in Brazil.

In addition, the amount of energy it takes to produce a given quantity of ethanol varies greatly for different crops (Figure 7.1). In Brazil, the extraction of the juice from sugarcane leaves considerable biomass, which is known as bagasse. This bagasse can provide all of the energy for the heat and electricity needed to produce ethanol. But cobs of corn do not have that same energy content, Goldemberg noted. As a result, fossil fuels need to be burned to produce ethanol from corn in the United States, making ethanol less attractive as a fuel in this context. Further, as the prices of fossil fuels rise, so will the cost of ethanol.

A concern unique to Brazil is the contention that the production of ethanol is causing the Amazon forest to be destroyed. But Goldemberg argued that this concern is misplaced. Most of the ethanol distilleries are in the southeastern



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