Corn cobs could be the new 'green' fuel at
Willmar plant
Nov 17 - McClatchy-Tribune Regional News - David Little West Central
Tribune, Willmar, Minn.
Willmar Municipal Utilities will test a new "recipe'' for producing energy:
corn cobs and coal.
The utility's power plant will conduct a test burn of cobs and coal later
this winter. If the test burn is successful, corn cobs could help the
utility comply with the state's renewable energy mandate and help boost
local farm income.
"Burning cobs may be able to help us meet our renewable energy goals and
support the local economy at the same time,'' says Bruce Gomm, Willmar
Municipal Utilities general manager.
The state is mandating all utilities, by 2025, have at least 25 percent of
energy needs met by renewable sources. Willmar hopes generating power from
biomass such as corn cobs, as well as its $10 million wind turbine project,
will help meet the mandate.
The test burn, slated for February, will determine if cobs burn
satisfactorily with coal and if the process is effective and efficient,
explains Jon Folkedahl of Willmar, a consultant working with the utility on
the corn cob project.
Second, the test will provide data for the Minnesota Pollution Control
Agency in issuing a permit that will allow Willmar to permanently burn cobs
and coal.
Meanwhile, Willmar is seeking an interim permit to allow the test burn,
according to Folkedahl.
Corn cobs have an energy value of 75 percent to 80 percent of Powder River
Basin coal, which Willmar buys and burns at the local power plant, located
near downtown.
"That's really good,'' says Folkedahl. "For biofuels, it's right at the top
of the list.''
There are several reasons for adding corn cobs to coal, according to the
University of Missouri, which is burning cobs to generate electricity at its
campus power plant:
- Cobs are abundant in the corn belt.
- Cobs are not used by most farmers.
- Cobs decompose slowly in the soil and offer little value as residue cover.
- Cobs have low sulfur and ash content, and have good heating value.
Folkedahl says cobs are considered a renewable fuel because cobs are
recycling carbon dioxide already in the air.
"When people talk about green energy and renewable fuels, that's really the
key is that the carbon dioxide released is not fossil, it's recycled,'' he
says.
The first step for Willmar is to collect the cobs. Folkedahl said
approximately 500 tons of cobs would be needed to provide data to satisfy
MPCA.
The collection process, which began Oct. 29 on 650 acres of corn land farmed
by Ryan and Lonnie Fosso of Pennock, is about two-thirds complete. The Fosso
farm was also the site in mid-October of cob harvesting by Chippewa Valley
Ethanol Company for fuel at the plant in Benson.
The Fossos have been good to work with, says Vernon Flamme of North Bend,
Ind., who's combining the corn and collecting the cobs for Willmar.
The corn is combined normally, but a special machine pulled by the combine
collects the cobs and blows the leaves and stalks out the back. Trucks are
hauling and piling the cobs on a runway, just west of County Road 5, at the
old city airport.
Flamme invented the cob collector, which he named the Cob Caddy. This year,
Flamme sold the patent for the machine to Vermeer Corporation, which renamed
it the Cob Harvester.
Flamme supports the use of corn cobs as a biomass fuel for power plants.
"There are a lot of these coal-fired plants in the country and the beauty of
the cob is it doesn't take any fertility or anything away from the land,''
says Flamme. "So why not save them and make energy out of them for the
country?''
The cobs will be burned at the rate of about 20 percent cobs to 80 percent
coal, according to Folkedahl. Once all emission controls are in place, the
utility hopes to burn as much as 75,000 tons of coal and 25,000 tons of
biofuels, particularly corn cobs, which would require 20,000 to 40,000 acres
of corn to be harvested for cobs in the area.
Initial rates peg the cost of cobs between $30 and $60 per ton. The utility
is paying the Fossos $40 per ton.
"We hope that we can start out small and as the market for corn cob grows,
farmers will invest in the harvest equipment and eventually the utility will
be able to reach that biofuels goal,'' Folkedahl says.
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