Tuesday, September 30, 2008

Ethanol More Efficient Than Previously Thought

via OWH, a new UNL study of the energy efficiency of ethanol shows a substantial increase in the net benefit of the alternative fuel. Previous studies based on older technologies showed less substantial benefits. The research showed that 13 gallons of ethanol were produced for every gallon of fossil fuels used in production.

"The Nebraska Corn Board reports that Ken Cassman, director of the Nebraska Center for Energy Sciences Research, said earlier studies that examined ethanol's energy balance sheet were based on "backward-looking data."

These studies looked at older technologies with regard to energy use in corn production, the biorefinery and co-product use," Cassman said. He said recent research conducted at the University of Nebraska shows that estimates for the energy balance of corn-based ethanol are much more favorable — in fact, two to three times more favorable — than previous estimates.

Cassman, a Heuermann professor of agronomy at the university, said ethanol has a substantial net positive direct energy balance — 1.5 to 1.6 more units of energy are derived from ethanol than are used to produce it. "Using dated information simply doesn't work in a world where the technology and efficiency of corn and ethanol production are rapidly improving over the years," he said."

In just the last five years, ethanol plants increased production 15% from each bushel of corn, while using about 20% less energy in the process. In addition, many earlier studies ignored the positive effects of by-products such as distillers grain used as an alternative livestock feed. More recent research also shows that the use of ethanol reduces the emmission of greenhouse gasses more than previous estimates.

While this won't end complaints about the subsidies that ethanol enjoys, (I am all for opening the market to sugar based producers) it may go a ways towards refuting those that claim the fuel is a net energy loser. The last two studies I saw were from Michigan State and U of Minnnesota, both of which showed about a 1.3 unit of energy benefit, so we've made quite a bit of progress since that time. Like any maturing technology, ethanol will liekly make further gains in energy efficiency and productivity.

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