2. BIOFUELS: Side effects of food-to-fuel are large (ClimateWire, 04/28/2008)

Jenny Mandel, ClimateWire reporter

The rapid run-up in global food prices has happened so fast that analysts are having trouble pinpointing the causes, but biofuels production plays a significant role, according to a leading researcher.

Timothy Searchinger, author of a major study that found most ethanol use causes increased greenhouse gas emissions, noted before a Capitol Hill audience Friday that 5 percent of world cereals are now being used for biofuels. "This has a big effect," he said. He paused. "People will eat less as prices go up."

Searchinger, a lawyer by training who is currently a visiting scholar and lecturer at Princeton's Woodrow Wilson School of Public and International Affairs, explained that the carbon lost from native ecosystems and soils when forests, grasslands and other land are cleared to make way for biofuel crop production far exceeds the amount of carbon emissions saved by the annual fuel output that can be raised on that land.

That thesis, published February 7 in Science magazine along with another study that independently reached the same central point, sent earthquakes through the biofuels community. At the time, it was full of enthusiasm over a renewed national mandate to use ethanol that passed in the Energy Independence and Security Act in December.

That legislation increased the national biofuels mandate fivefold, to 36 billion gallons by 2022, with corn allowed to account for up to 15 billion gallons. The act includes requirements that the new biofuels emit fewer greenhouse gases than does gasoline, including not only direct emission sources but also indirect sources like land use change.

'Convert waste, not food and forest'

At Friday's event, Searchinger said the emissions resulting from land conversions are so significant that even if corn-based ethanol appeared in our gas tanks magically, without any of the petroleum use associated with tilling and fertilizing the corn, or refining the fuel and delivering it, and if that fuel burned in the vehicle with no carbon emissions, the land conversion factor alone would make gasoline a more favorable fuel choice.

On the food side, he said his analysis suggested that as global food prices rise, about half the expected drop in demand will come from developed countries. That half is not a big problem. The other half, he said, is likely to come from developing countries where many people are malnourished.

Governments should adopt a simple policy to avoid both the conversion-based emissions and competition for food grains, Searchinger said: "Convert waste, not food and forest."

Joining Searchinger on the panel were other researchers at the forefront of the debate on biofuels emissions.

Joseph Fargione, regional science director for The Nature Conservancy's central U.S. region and David Tilman, a professor of conservation biology and ecology at the University of Minnesota, were authors of the other Science study that found emissions problems with biofuels.

Tilman estimated that the United States could produce between 270 million and 430 million tons of biofuels per year without competing with food for fertile land. That production could come from: 80 million to 100 million tons per year from perennial plants (long-lived species that would be harvested by mowing, as opposed to corn, which is razed and replanted for each crop cycle) grown on degraded land; roughly 100 million to 150 million tons per year of ethanol from corn and wheat residues that could be harvested without threatening soil quality; 70 million to 140 million tons per year from forest residues; and 20 million to 40 million tons from reclaimed paper and paperboard waste.

Tilman cited the need for additional research in almost every category, though, including how to optimally manage perennial plantings, what forest residues can be harvested without causing erosion or stealing soil nutrients, and to what extent wheat and corn plant residues can be collected without damaging soil quality.

In the United States, Tilman said, degraded and marginal land data is collected in detailed county-level maps maintained by the Agriculture Department, and accurate productivity estimates can be made. But Searchinger noted that much of the abandoned farmland in this country has turned to forest, which sequesters large amounts of carbon.

Plug-in cars could aid shift toward 'sustainable' standard

Daniel Kammen, founding director of the Renewable and Appropriate Energy Laboratory at the University of California, Berkeley, and co-director of the Berkeley Institute of the Environment, did not disagree with his peers on the land conversion problems that biofuels raise. But he said analyses should look at ethanol in the context of alternatives.

"There is no peak 'dirty energy,' even if there is 'peak [conventional] oil,'" Kammen said, noting that as the easily accessible oil reserves are used up, alternatives like coal and natural gas will increasingly be used for transportation at much higher environmental costs. The U.S. Air Force is interested in using liquid fuel from coal, for example, which emits far more greenhouse gases than does conventional fuel (Greenwire, Dec. 6, 2007).

California has instituted a low-carbon fuel standard setting current consumption as a benchmark and calling for energy to be 10 percent less "carbonized" by 2020, Kammen said. While calling for "low-carbon" rather than "alternative" fuels is important, he said, in the future that should shift to a "sustainable" standard that takes into account factors like the water usage associated with production.

Kammen also spoke out strongly for plug-in vehicles that could be fueled primarily from electrical energy. In California, where power production is relatively clean, one million vehicles could be charged at night without necessitating any changes to the electric infrastructure, he said.

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