Midwestern ethanol plants use much less water than western plants, study says

Apr 15, 2009

Ethanol production in Minnesota and Iowa uses far less water overall than similar processes in states where water is less plentiful, a new University of Minnesota study shows.

The study, which will be published in the April 15 edition of the journal Environmental Science and Technology, is the first to compare water use in corn-ethanol production on a state-by-state basis. The authors used agricultural and geologic data from 2006-2008 to develop a ratio showing how much irrigated water was used to grow and harvest the corn and to process it at ethanol plants.

Among the major ethanol-producing states, Iowa uses the least water, with about six gallons of water used for each gallon of ethanol. Minnesota, which in 2007 produced roughly a third as much ethanol as Iowa, uses about 19 gallons of water per ethanol gallon.

States where irrigation is needed to grow corn fared far worse than those where almost no corn is irrigated. California, which produces only a tiny fraction of the nation's ethanol but irrigates most of its , is the largest water consumer, at about 2,100 gallons of water per gallon of ethanol. South Dakota, with total production roughly equal to Minnesota's, uses about 96 gallons of water to produce one gallon of ethanol.

Water usage could be an important factor in policy decisions about where ethanol plants are built. The study "highlights the need to strategically promote development in states with lower irrigation rates and less groundwater use," the authors say. All the states with high water usage ratios are classified by the federal government as likely to experience water shortages in coming years.

"Both energy security and water security are too important; improvement of one of them should not be made at the expense of another," said Sangwon Suh, an assistant professor in the university's department of and biosystems engineering and the study's lead author. "Understanding the dependence of on and its spatial disparity will be critical in implementing the biofuel policy in the United States."

Source: University of Minnesota (news : web)

Explore further: Hurdles to US climate change action are in economics and politics, not divided science

Related Stories

Ethanol production said increasing erosion

Jul 06, 2005

Large-scale farming of sugar cane and corn for ethanol fuel is increasing erosion and reducing biodiversity, Washington State University researchers say.

Turning corn fiber into ethanol

Jun 01, 2006

Tony Pometto held up a laboratory flask swimming with little balls of mold. This, said the Iowa State University professor of food science and human nutrition, is the kind of fungus that Iowa State researchers have used to ...

Recommended for you

Deathly effect of heatwaves ignored

54 minutes ago

Heat is an emerging problem in Sydney, but despite having its strongest effects on the poor, the elderly, the disabled and the very young, most community services don't formally cater for the impact of heatwaves ...

Siberia wildfire toll rises to 34

54 minutes ago

Raging wildfires in recent weeks killed 34 people, the emergencies minister said Tuesday in a new toll as President Vladimir Putin visited the stricken region.

Rising carbon dioxide levels stunt sea shell growth

1 hour ago

Scientists have discovered that stunted growth can be a genetic response to ocean acidification, enabling some sea creatures to survive high carbon dioxide levels, both in the future and during past mass ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

lengould100
5 / 5 (1) Apr 15, 2009
2,100 gallons of water per gallon of ethanol.
Ridiculous waste of resources. And moving ethanol production out of irrigation territories will only force the food-grain industry to move TO the irrigation territories. Stupid system. Running SUV's on human food.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.