Shock study: Corn biofuels cause more global warming than fossil fuels
by: J. D. Heyes
A new study shows that biofuels which are manufactured from leftover materials of harvested corn are worse than gasoline in causing harmful atmospheric emissions in the short term, a finding that challenges the government's assertions that they are a much cleaner alternative to help combat climate change.
According to E&E Publishing, using corn cobs and stover to manufacture cellulose biofuels actually increases emissions from the plant matter and other residue components being burned at biorefineries around the country, rather than being mixed into the soil and remaining trapped as organic soil matter, said researchers from the University of Nebraska-Lincoln.
"If the residue had not been removed, some of it would be left in the field and be naturally added to maintain soil carbon," said Adam Liska, lead author of the paper and assistant professor of biological systems engineering at the University of Nebraska.
The Associated Press further noted:
A $500,000 study paid for by the federal government and released [April 20] in the peer-reviewed journal Nature Climate Change concludes that biofuels made with corn residue release 7 percent more greenhouse gases in the early years compared with conventional gasoline.
While biofuels are better in the long run, the study says they won't meet a standard set in a 2007 energy law to qualify as renewable fuel.
Wisconsin, Minnesota carry more carbon losses'
Reports said that researchers used a computer model to estimate emissions across the nation's so-called Corn Belt, which consists of about 128 million acres (or about 96.8 million football fields). A removal rate of about 2.68 metric tons per acre per year over five to 10 years may decrease soil organic carbon by some 200 pounds per acre per year.
"This can add an average of 50 to 70 grams of CO2 per megajoule of biofuel. At the high end, this makes these biofuels emit about 7 percent more carbon dioxide than gasoline, making them slightly worse from a climate perspective. Over 10 years, it would reduce gasoline emissions by about 15 percent," E&E reported.
Researchers said that Wisconsin and Minnesota were found to carry higher carbon losses. They estimate that the cold weather in these states may slow the release of soil organic carbon into the atmosphere. Liska says that the higher corn yields in these states can add larger amounts of carbon to the soil, which then represents a larger loss if corn residue is collected.
The AP reported that the study's findings are bad news for what are known as cellulosic biofuels, which have received more than $1 billion in federal subsidies and support but have nevertheless struggled to meet volume targets mandated by law. Some 50 percent of the initial market in cellulosics is estimated to be derived from corn residue.
Biofuel industry officials, as well as those within the Obama administration, immediately rebuked the findings and said the research was flawed.
Douglas Karlen, a research leader in the Agriculture Department's Agricultural Research Service, said, for example, that the study was too simplistic in its analysis of the loss of carbon from soil, which he says can vary from field to field. Researchers also vastly overestimated how much residue farmers actually remove once the market is up and running.
'I knew this research would be contentious'
And, adds Jan Koninckx, the global business director for biorefineries at DuPont: "The core analysis depicts an extreme scenario that no responsible farmer or business would ever employ because it would ruin both the land and the long-term supply of feedstock. It makes no agronomic or business sense."
Later in the year, DuPont is scheduled to complete construction on a facility estimated to cost in excess of $200 million in Nevada, Iowa, that is expected to produce some 30 million gallons of cellulosic ethanol using corn residue from local farms. A DuPont-financed assessment said the ethanol it will make at the facility could be 100 percent better than gasoline in terms of greenhouse gas emissions.
"I knew this research would be contentious," said Liska. "I'm amazed it has not come out more solidly until now."
One other aspect of using ethanol-laced fuel instead of 100 percent fossil fuel: The ethanol-laced fuel gets worse mileage per gallon, so more of it must be produced and burned to go the same number of miles.
Learn more: http://www.naturalnews.com/045330_corn_biofuels_fossil_fuels_global_warming_myths.html#ixzz330Zl7tq4
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