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Thursday, June 08, 2006

Biofuels: Miracle Cure or Path to Greater Destruction?

According to officials with the United Nations Food and Agriculture Organization (FAO), rapidly rising oil prices and the growing urgency of climate change could spur a major international shift to bio-energy use in little more than a decade. Alexander Müller, FAO’s new Assistant Director-General for Sustainable Development, made the prediction at an April 25 briefing in Rome, noting that “Over the next 15 to 20 years we may see bio-fuels providing a full 25 per cent of the world’s energy needs.”

At first glance, these fuels, derived from plants and other organic material, seem like a miracle cure for the planet’s energy woes. Roughly one-quarter of global greenhouse gas (GHG) emissions are produced by the transport sector, and biofuels, including ethanol and biodiesel, are the only existing renewable fuels compatible with current transportation infrastructure. Studies show that biofuels generate a fraction of the pollutants of traditional petroleum-based fuels, and the plants that produce them remove carbon, a climate-altering GHG, from the atmosphere. Biofuels also have the potential to reduce foreign oil dependency, lower fuel prices, increase income for farmers, and provide a host of new jobs. Liquid biofuel can even be made from some of the very materials that contribute to the planet’s mounting solid waste problem, such as wood residues and sewage.

Yet debate has raged over whether growing, harvesting, producing, and distributing these fuels—particularly ethanol derived from corn—ultimately requires more fossil energy use than would be displaced with the biofuel itself. Most of the biofuel crops grown in the world today require petroleum-based pesticides, fertilizers, and other chemical inputs to produce on a competitive scale, and virtually all farm equipment and factories run on fossil fuels. As demand rises rapidly, producers may also adopt even less environmentally friendly practices in the short term. One new ethanol plant in Iowa, for example, now burns 300 tons of coal a day to convert corn into biofuel, rather than using cleaner-burning natural gas as most U.S. facilities do, reports the Christian Science Monitor. Other plants could similarly switch if natural gas prices remain high.

On balance, however, a recent study in Science magazine, drawing on more detailed data on fertilizer requirements and the efficiency of ethanol mills, concludes that corn ethanol could reduce GHG emissions by some 13 percent compared with gasoline. The reductions can be even greater with sugar cane—as high as 87–96 percent, according to research from Brazil’s São Paulo Sugar Cane Agroindustry Union—in part because the crop can be grown at higher yields with fewer fossil inputs. And ethanol derived from cellulosic material, including crop residues and woody plants, offers the potential of reducing GHG emissions by more than 100 percent, according to the International Energy Agency, particularly if bio-energy is also used in producing the fuel.

But there are other reasons to approach the biofuel revolution with caution. As planting biofuel crops becomes more lucrative, farmers have greater incentive to convert ecologically valuable areas, such as forests and wetlands, to cropland—as has occurred in Southeast Asia, where rainforest habitats have been cleared to grow plantations for palm oil, a popular biodiesel feedstock. And as energy crops become more profitable than food crops, competition between food and fuel needs could intensify and food prices in some industries could rise. Already, prices for sugar and rapeseed oil have risen in the past year due to increased interest in biofuels.

Solutions to these problems exist but will need to be supported and promoted far more widely, says Suzanne Hunt, biofuels project manager at the Worldwatch Institute. Applied research, international collaboration, and strong policy support are essential to the proper implementation of widespread biofuel use. The U.S.-based Natural Resources Defense Council, for example, is currently working with Chinese industries and government agencies to explore the practical use of biofuels. The effort is part of a larger project to rethink traditional energy sources in China, where energy demand is rising rapidly.

The private sector will need to strengthen its efforts to meet increased demand for biofuels as well. With the continued improvement of cellulosic technology, the ethanol feedstock supply is expected to shift from edible crops like corn and rapeseed oil to fast-growing grasses like switchgrass and miscanthus, agriculture and forestry residue, and even the organic portion of municipal solid waste. Much of this material can be obtained from land less suitable for food crops, reducing competition with food markets. Though the cellulosic conversion process is still prohibitively expensive, the costs of cellulosic biofuel production are declining, and one company, Iogen Corporation of Canada, is already selling cellulosic ethanol commercially.

Nor does the biofuel industry itself have to run on climate-damaging fossil fuels, as Brazil’s ethanol producers have already proven. For years, the country’s sophisticated “biorefineries” have burned the waste residues of sugar cane—known as bagasse—to power their operations, offsetting the need for expensive oil imports. According to a New York Times article published in April, Brazil could become energy self-sufficient as early as this year as a result of its dedicated investments in sugar cane for fuel and power. Industries elsewhere can learn from this example by using similar bio-based resources available to them, such as corn stalks, biogas from manure, or other fibers.

Biofuels can be produced and used in a way that will reduce GHG emissions, create jobs and profits, lessen dependence on oil, and keep consumer costs down. But if care is not taken in creating an environmentally friendly biofuel infrastructure, the positive effects of this coming energy “transformation” will be greatly diminished.


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