If you’re spending upwards of $1 million per month for natural gas to power your ethanol plant, a serious look at renewable resources such as corn cobs, wood chips, even saw dust (sprayed with glycerin for dust control) to offset this cost seems smart.

Well, one of Minnesota’s more innovative ethanol facilities is not only thinking smart, they’re testing the process. Biomass gasification is the technical term for the project under way at Chippewa Valley Ethanol Co. in Benson.

“We’re unlocking the ability to keep most of the $13 million spent each year on natural gas and transfer this instead to our members,” said commodities manager Chad Friese, speaking at the annual meeting of ProAg of Renville County earlier this year.

Working with Frontline BioEnergy of Ames, Iowa, the CVEC is piloting this new biomass technology to see if green energy can in fact replace natural gas, a non-renewable energy source. Permitted by Minnesota Pollution Control Agency last spring for a limited first-year trial run on this new technology, the CVEC renewed its permit with the MPCA in May and hopes to expand 400 percent from its original permit. Gasification is the thermo-chemical conversion of biomass feedstocks into combustible gases in the presence of limited amounts of oxygen.

“We’re presently replacing about 30 percent of our natural gas with an eventual goal of 90 percent replacement,” Friese said. “We’re still learning about what are all the necessary ingredients to get a better-burning synthetic gas. We’re also trying different feedstocks, and corn cobs appear to be the most logical and convenient biomass feedstock.”

Last year, the CVEC purchased cobs harvested from about 500 acres of corn. Average cob yield is about three-quarter ton per acre. About 112,000 corn acres will eventually be needed to provide the cobs should this trial run prove that cobs are first choice.

According to Friese, the CVEC expects to be paying $55 to $60 per ton for cobs. Still to be decided are handling logistics, such as: Will cobs be delivered to pre-designated piling sites much like the sugar beet harvest is handled? Should cobs be stored in plastic bags much like dairy farmers handle their forages? Should cobs be chopped, or ground prior to being fed into the gasification chamber?

Vermeer Manufacturing of Pella, Iowa, is now marketing a cob-harvesting unit hitched behind corn combines. Loftness Equipment also has machinery for filling cobs into plastic bags.

“At this stage I describe what we are doing as boundless technology since we are still discovering,” Friese said, adding that last summer when natural gas was $13.65 per million BTUs it was a no-brainer. Now with natural gas about $4, the CVEC needs cheap biomass feedstocks. “With $40 crude oil it’s difficult to compete on a green energy economy. But the experts tell us that with a strengthening world economy, the price of crude will strengthen also.”

The economics of gasification are exciting. Friese said that even with $10 natural gas, they could pay up to $85 per ton of cobs. “There are no new oil wells being drilled. So I think it inevitable that crude will soon be rising.”

The CVEC is a 900-member producer co-op currently marketing about 48 million gallons of ethanol yearly plus about 120,000 tons of distillers dried grain feeds, a specialty product called Shaker’s Vodka and a growing market for certified organic alcohol, especially important for certain food processors and pharmaceutical firms. For more information, log on to www.cvec.com.