Ethanol derived from corn requires much more water than was previously thought, according to a study by the researchers at the University of Minnesota. That water need also differs greatly from state to state depending on regional irrigation needs.
Prior studies had said that the water needed to convert one liter of corn-derived into fuel at all stages should be 263 to 784 liters, the newer study changes that theory. It states that 5 to 2,138 liters of water per liter of ethanol will be needed.
That’s a vast difference that could make the production a bigger problem than other issues which have arisen. Environmental concerns from pollution from fertilizer to greenhouse-gas emission from the production of the ethanol could be a deterrent for the product.
There is also the concern that the corn needed would be competing for food crops.
Technology Review reports on the new study out in the journal Environmental Science and Technology:
“Ethanol consumes more water over time as corn production extends to regions that need extensive irrigation,” says Sangwon Suh, an assistant professor of biosystems engineering at the University of Minnesota and coauthor of the study. “That means more water is needed to produce a given unit of ethanol over time.”
Considering that ethanol uses more energy to be produce than it releases may leave this fuel as a dead end.
Even as the new information comes into play The U.S. Energy Independence and Security Act of 2007 mandates that ethanol production increase from 34 billion liters in 2008 to 57 billion liters by 2015.
Jerry Schnoor of the University of Iowa, in Iowa City, says that ethanol producers are already planning additional production facilities in all states to meet the 2015 goals. “We’re already in an unsustainable situation in terms of water use, already drawing down aquifers like the Ogallala,” Schnoor says of the vast underground water source stretching from South Dakota to northern Texas. “This would exacerbate that decline if we expand in these irrigation states.”
Ethanol’s answer may become finding ways to make the fuel with alternative products like grass, wood and sawdust says Jerald L. Schnoor.
The study was funded in part by the Department of Energy and the state of Minnesota.