Do you notice any similarities between the two maps below? The top map shows us the corn production regions in Nebraska in 2012 (a drought year), the dark green areas having the highest production.
The red stars represent the ethanol plants in Nebraska.
The second map from year 2005 shows us the regions of Nebraska which irrigate most heavily using groundwater withdrawals. As you can easily see, the regions which irrigate most heavily, are the same as those that were most productive for corn in 2012.
Nebraska ranks as the third highest corn producing state, and it is also the state that is gifted with the most underground Ogallala Aquifer water. Seed corn companies prefer to use Nebraska’s irrigated corn acres for reliability during drought years and ethanol plants also like the reliability of corn production that Nebraska’s irrigated acres can provide. In 2008, 3.6 million acres in Nebraska were irrigated using center-pivots, and that number has surely grown since then.
According to a 2011 article out of Columbia University: “In Ohio, because of sufficient rainfall, only 1% of the corn is irrigated while in Nebraska 72% of the crop is irrigated. It takes 19 gallons of water to produce a bushel of corn in Region 5, 38 gallons in Region 6, and 865 gallons in Region 7. (Region 5 includes Iowa, Indiana, Illinois, Ohio and Missouri; Region 6 includes Minnesota, Wisconsin and Michigan; and Region 7 includes North and South Dakota, Nebraska and Kansas.) The Baker Institute estimates that producing the corn to meet the ethanol mandate for 2015 will require 2.9 trillion gallons of water.”
Nebraska ranks second of all the states in ethanol production. I was curious to find out what percent of Nebraska’s corn was turned into ethanol. The clearest and most recent numbers that I could find using a non-drought year belong to 2011.
To do the calculation, I used data provided by the National Corn Growers Association:
1,536,000,000 bushels corn was produced in 2011 in Nebraska
2.089 billion gallons of ethanol operating capacity* in 2011 in Nebraska
(if) 1 bushel of corn produces 2.8 gallons ethanol
then the % of corn going to ethanol in the state of Nebraska in 2011
= 49 %
From the University of Nebraska’s website, the issue becomes is it worth it?
Life cycle analysis (LCA) of ethanol production from corn grain has yielded a net energy ratio of 1.2 to 1.45 (Liska et. al. 2009). This represents just a 20 to 45% positive energy balance when producing ethanol from corn. This number has been the criticism of corn ethanol because of the large amount of fossil energy used to produce ethanol.
Yes, I know, the ethanol industry would argue that today’s conversion factor is more efficient, however… irrigated corn requires higher energy inputs even if the price of the water is considered to be free. It is possible that the energy returned on irrigated corn converted to ethanol in Nebraska is negative or about 1:1.
Where is the outrage on that, I ask the Nebraskans who proudly protested the Keystone pipeline to protect the state’s water?
In conclusion, the majority of the corn produced in Nebraska is produced by using irrigation water. And, around half of the corn produced in Nebraska is being converted into ethanol. Given ethanol’s negligible energy return, it looks like a hamster on a wheel that gets nowhere, a frivolous thing to do with this precious fossil water.
*note that this number should be quite accurate because ethanol plants were operating at near 100% capacity in 2011 in Nebraska.
See previous post: Pivots and Loss of Habitat in Flyover-Country