CVEC looks at harvesting corn cobs as form of biomass fuel
PRIAM -- Their grandparents knew the value of corn cobs as a fuel, and used them to help warm the house or heat up the oven for baking bread.
Yet brothers Lonnie Fosso and Ryan Fosso couldn't help but admit their amazement Wednesday as they watched two combines harvest their corn while also collecting the corn cobs. The corn cobs are being harvested as fuel for the Chippewa Valley Ethanol Company plant in Benson.
"I wish they could see this,'' said Lonnie Fosso.
Dozens of people did. The harvest at the Fosso farm south of Priam served as the first of three demonstration sites for a first-of-its-kind project in the region. Chippewa Valley Ethanol Company has been powering some of the operations at its 47 million-gallon-a-year ethanol plant by feeding biomass to a gasifier. The Frontline Technology system turns the biomass -- currently wood chips -- into a synthetic gas that can replace natural gas.
After more than four months of trial use, the gasifier has proven its ability to displace about 25 percent of the natural gas used by the plant.
The goal is to someday see biomass replace 75 percent to perhaps as much as 90 percent of the natural gas used at the plant, according to Gene Fynboh, a member of the board of directors and coordinator for the biomass harvest project.
Chippewa Valley Ethanol Company would like corn cobs raised by its members to become the biomass fuel of choice. Corn cobs are relatively easy to collect, store and handle when compared to other types of biomass. They have good energy content. And, they hold very little of the nutrients that are returned to the soil by corn stover, Fynboh said.
The cooperative would rather pay its farmer members for corn cobs and circulate the dollars at home than buy expensive fossil fuel from sources a long ways from home, Fynboh said. The evidence so far indicates that locally produced biomass is a lower-cost fuel than natural gas, he added.
Modern technology makes it much more efficient to convert biomass to energy than when the Fossos' grandparents tossed corn cobs into the wood stove. But in some respects, we're still stuck in the days of the bang board wagon in terms of the technology and knowledge needed to harvest and store corn cobs on a large scale.
"This is something we haven't done for 50 years,'' Fynboh said. "We have to learn it all over again.''
Chippewa Valley Ethanol Company and the University of Minnesota West Central Research and Outreach Center obtained $250,000 in grant funds to find a better way. At the Fosso farm, combines demonstrated two different ways to collect the corn cobs that would otherwise have been chopped and spit out with the rest of the corn stover on to the field.
One combine towed a pull-behind, Vermeer CCX770 Cob Harvester to collect the cobs. The other had a Ceres Ag Residue Recovery System mounted piggyback on it for the same purpose. With either system, the cobs were periodically dumped into trucks or onto piles.
Either system will add fuel costs to the harvest, and necessitate some additional help. An extra truck to haul cobs and a pay loader to build the piles were at work.
Fynboh said goal number one is to harvest the corn as efficiently as if the cobs were not being collected. The Fossos said that is a must for them: Farmers cannot afford to jeopardize their corn harvest in any way.
The Fossos and Chippewa Valley Ethanol Company are also interested in knowing how the costs of harvesting the corn cobs compare to their market value as a fuel.
Harvesting corn cobs as fuel could increase the overall economic return on corn fields, Fynboh said. "We have a resource that is right under our nose here,'' he said.
Speaking of the ground, it too is under study. Fynboh said the research will examine how much of the biomass can be taken without adversely affecting the soil or future yields.
Fynboh said Chippewa Valley Ethanol Company has lined up 5,000 acres of corn from its members to harvest for the research. The cooperative's 980 owner-members raise corn on 112,000 acres. That is ample to supply all of the biomass energy the company is seeking, Fynboh said.