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Ethanol 101

Ethanol is an alcohol-based alternative fuel. The fermented product of corn starches, ethanol can be made by dry-mill, wet-mill, or biomass processing. Through one of these processes, corn is fermented, distilled, and separated into a starch-filled liquid (ultimately become ethanol), solids, and corn oil. These co-products and by-products from ethanol production have become staples in food and manufacturing industries.

Dry Mill Ethanol Process
Credit: https://ethanolrfa.org/wp-content/uploads/2020/02/drymill_process.jpg

Gasoline and Ethanol Blends

Ethanol-blended fuel, specifically E85 and E15, differ from fossil fuels gasoline in their source; corn is specifically grown to produce ethanol and useful by-products, while traditional gasoline is refined from crude oil. Nearly all gasoline contains up to 10% ethanol because any vehicle can run on up to a 10 percent blend; the percentage is often displayed on the gas pump. Ethanol raises the oxygen content of gasoline to help mitigate air emissions.

The two most common ethanol blends are E85 and E15. E85 is 85% ethanol and 15% gasoline and, conversely, E15 is 15% ethanol and 85% gasoline. Both E85 and E15 can only be used in specially designed flex-fuel vehicles, so it’s best to consult a vehicle’s handbook or manufacturer’s specifications before filling up a vehicle with ethanol.

What are the by-products of ethanol production?

RFA: “On average, one bushel of corn processed by a dry mill ethanol plant can now produce:

  • 2.92 gallons denatured fuel ethanol o 15.86 pounds of distillers grains animal feed (10% moisture)
  • 0.80 pounds of corn distillers oil for animal feed and biodiesel production
  • 16.5 pounds of biogenic carbon dioxide for food, beverage and chemical manufacturing https://ethanolrfa.org/co-products/

Indiana Biorefineries

There are 14 biorefineries in Indiana that produce ethanol. For an analysis of the GDP impact of ethanol refineries, view the 2014 Indiana Corn Marketing Council report. These report excepts show that ethanol and its co-products have generated a positive impact on Indiana’s economy.

“Ethanol in the U.S. and Indiana has become the main driver of economic growth supporting, directly or indirectly, crop farmers and businesses within their supply chain.”

“Indiana’s ethanol industry generated economic activity or revenues from ethanol and its interlinked industries in 2014 in the order of $3.6 billion.”

“This is a total impact and includes all revenue from ethanol production co-products, plus revenues generated from indirect and induced impacts.”

Table guide:

  • Operating capacity represents how many millions of gallons per year the plant can produce.
  • Bushels of corn is the approximate amount of corn needed for a plant to operate at full capacity for a year.
  • Distillers dried grain with solubles (DDGS) are a co-product of ethanol production and is used as a high-protein animal feed alternative to corn- and soy-based animal feeds. A 2011 USDA study estimates “a metric ton of DDGS can replace, on average, 1.22 metric tons of feed consisting of corn and soybean meal in the United States.” Because the co-product of ethanol production results in a more-efficient livestock and poultry food sources than direct corn or soy feed, the impact of growing corn for ethanol is less impactful to the livestock food supply chain. Source
  • Corn oil is a by-product of ethanol production that is used in poultry feed and biodiesel production.
  • CO2 can be captured during the fermentation process, and is a by-product that is sold for use in carbonation for bottling, dry ice, refrigerant, and other segments of the food and food processing industries.
Indiana Ethanol Plants Production Statistics
data from https://ethanolrfa.org/biorefinery-locations/
Company Name Plant Location Operating Capacity Bushels of Corn DDGS (tons) Corn Oil (pounds) # of Employees CO2
Cardinal Ethanol Union City 125 Million 36 Million 340,000 23 Million 52  
Central Indiana Ethanol Marion 55 Million 20 Million 160,000 11 Million 62 115,000 tons
Green Plains Renewable Energy Bluffton 120 Million          
Grain Processing Corp. Washington 35 million          
Green Plains Renewable Energy Mount Vernon 90 million          
Iroquois Bio-EnergycCompany Rensselaer 57 million 20 million 150,000 13 million 35-40  
South Bend Ethanol South Bend 65 million 23 million 177,000   60  
POET Biorefining Alexandria 76 million 24 million 190,000 24 million 45  
POET Biorefining Shelbyville 92 million 31 million 246,500   43  
POET Biorefining Cloverdale 92 million          
POET Biorefining North Manchester 68 million 24 million 178,000   40  
POET Biorefining Portland 76 million 26 million 200,000 236,000 42  
The Andersons Clymers Ethanol Clymers 110 million 40 million 350,000      
Valero Renewable Fuels Company Linden 130 million 46 million 385,000 32 million 70  
Valero Renewable Fuels Company Mount Vernon 100 million 37 million 320,000   65