Touring an ethanol plant

How many ears of corn are there on a single stalk of corn that has been grown for use as grain? The answer, and its implications for the future of ethanol, in a minute.

Recently, I had the pleasure of riding along with Nelson Graham, an agronomist with UAP Corporation, as he checked the condition of bean and corn crops grown by two of his client farmers in Dane County, Wisconsin. Afterward, we drove north to Cambria to tour the United Wisconsin Grain Producers (UWGP) Ethanol Plant. The plant, only a few years old, produced more than 50 million gallons of ethanol last year. Capacity of the plant in its present configuration is 60 million gallons.

The plant is essentially a large distillery. Corn grown by area farmers (18 million bushels last year) is combined with water (up to 500,000 gallons per day) and two enzymes. The enzymes convert the starch in corn to sugar. Yeast is then introduced to convert the sugar to alcohol. The mix reaches 13 percent alcohol content before it is distilled to remove the water. Ultimately, the alcohol reaches 200 proof. The ethanol is sold to oil companies where it is blended with gasoline in ratios ranging from 10% to 85% ethanol.

The UWGP plant produces two byproducts. One of the byproducts is distiller’s grain, which contains the residual fat and protein content of the corn. Some of it is sold in a wet state to area farmers for use as feed. The remainder is dehydrated in large drum dryers to create a meal that is shipped all over the world, also for use as animal feed. Click on the image for a larger view of dried distiller's grain.

The other byproduct is CO2. An enzyme in the yeast breaks down simple sugar during fermentation, forming ethanol and carbon dioxide:

C6H12O6 ----- 2 CH3CH2OH + 2 CO2

At this point, UWGP is not willing to invest in sequestering or otherwise offsetting the CO2. Rather, the CO2 is simply allowed to dissipate. Ethanol supplants the need for a percentage of the gasoline we use, but at a price in terms of CO2 emissions.

On Friday, July 25, 2008, Monsanto, Archer Daniels Midland, Deere & Company and DuPont announced a new cooperative initiative. Their Alliance for Abundant Food and Energy will spend several million dollars to advertise and lobby so as to build the case that new approaches can make crop-based fuels like ethanol and bio diesel economically feasible while still meeting the food needs of the world.

Not long ago the CEO of Monsanto claimed during an interview broadcast on CNBC that his company possesses the knowledge to create hybrid corn seed that will double the yield per acre with fewer inputs. However, the article on the Alliance suggested that Monsanto “hopes to double the yield-per-acre of crops like corn and soybeans by 2030” and that Pioneer Hi-Bred, a division of DuPont, plans to boost yields produced by its seeds by 40 percent within a decade.

What does the Alliance want? Clearly they want to counter the efforts of the Wholesale Grocers Association and other outspoken critics of ethanol. In addition, they want to preserve the current federal mandate that requires the use of 9 billion gallons of alternative fuel annually by 2009. Finally, the Alliance hopes to obtain funding for agricultural research and development that it says is needed to increase crop yields.

Now, back to the question posed at the outset. Today, corn that is grown for grain produces one ear per stalk. It is unlike sweet corn, the usual point of reference for consumers with any experience picking corn, which can produce multiple ears per stalk.

As we drove away from the ethanol plant, Nelson noted that corn is capable of producing an ear wherever a leaf emerges from the stalk. However, corn has been bio engineered to create a uniform crop in an effort to make farming increasingly productive. In addition to the single ear, the stalk has been strengthened, separation between stalks has been reduced, and resistance to disease has been enhanced.

So, I will leave you with more questions. If Monsanto has the intellectual wherewithal to double yields now (two ears per stalk?), why will it take federal dollars to fund the research? As importantly, why will it take until 2030 to see such crops? Between now and then, how do we balance the need for fuel and food if corn-based ethanol remains the dominant alternative?


A note about Nelson Graham. In addition to his work as an agronomist, Nelson is an accomplished singer-songwriter-musician. Many of his songs are poignant observations about life and change in the country. Others reflect his commitment to social and political justice. Nelson is on the Board of Art in the Barn and performs frequently in and around Madison. Sample his work at www.nelsongraham.com.