Recent innovations in corn ethanol production have resulted
in increased yield per bushel and less energy needed for production, according
to a new study.
The study, “2012 Corn Ethanol Emerging Plant Energy and
Environmental Technologies,” found thermal energy use at a typical dry mill
ethanol plant has fallen 9 percent since 2008, meaning the carbon footprint of
corn ethanol continues to shrink.
The authors, Steffen Mueller of the University of Illinois
at Chicago Energy Resources Center, and John Kwik of Dominion Energy Services
LLC, wrote in summary: “Our work includes an assessment of over 50 percent of
operating dry grind corn ethanol plants. On average, 2012 dry grind plants
produce ethanol at higher yields with lower energy inputs than 2008 corn
“Furthermore, significantly more corn oil is separated at
the plants now, which combined with the higher ethanol yields results in a
slight reduction in DDG production and a negligible increase in electricity
The table below summarizes the 2012 survey results and
contrasts them with 2008 operating efficiencies:
* Yield — anhydrous/undenatured, gallon/bushel: 2.82 for
2012 corn ethanol and 2.78 for 2008 corn ethanol;
* Thermal Energy — Btu/gallon, LHV: 23,862 for 2012 corn
ethanol and 26,206 for 2008 corn ethanol;
* Electricity Use — kWh/gallon: 0.75 for 2012 corn ethanol
and 0.73 for 2008 corn ethanol;
* DDG Yield dry basis, including corn oil — pounds/bushel:
15.73 for 2012 corn ethanol and 15.81 for 2008 corn ethanol;
* Corn Oil Separated — pounds/bushel: 0.53 for 2012 corn
ethanol and 0.11 for 2008 corn ethanol; and
* Water Use — gallon/gallon: 2.70 for 2012 corn ethanol and
2.72 for 2008 corn ethanol.
“Once again, the innovation and dedication of this industry
is borne out in the science and data,” said Bob Dinneen, president and CEO of
the Renewable Fuels Association.
“Ethanol producers are constantly evolving, innovating and
improving the production process. As a result, today’s ethanol industry is using
less energy and water than ever before and greatly reducing GHG emissions
associated with the corn ethanol lifecycle.
“Today’s ethanol producers are conscientious stewards of
this country’s precious resources and this country’s energy future. The ethanol
industry is a classic example of American ingenuity driving success.”
“This study provides critical data for reducing the overall
carbon footprint for corn starch ethanol,” added Dave Loos, Illinois Corn
Growers Association technology and business development director. “Of course,
changing the legislated definition of cellulosic ethanol to include corn starch
based ethanol is a primary goal of Illinois Corn.”
The study also summarizes several new technologies being
adopted by ethanol producers and feedstock providers.
It was funded with Illinois corn checkoff monies, partnered
with investments from the National Corn Growers Association and Monsanto.
Additional support for the study was provided by the Renewable Fuels
Association, Growth Energy and the Nebraska Corn Board.