GRE needs crop residue to process into ethanol, other products at biorefinery

Feedstock needs and farmers’ involvement were the focus of Great River Energy’s meeting on the Dakota Spirit AgEnergy biorefinery project Wednesday in Jamestown.

Area legislators, Jamestown/ Stutsman Development Corp. staff and board members, representatives of local and regional utilities, farmers, Stutsman County commissioners and other interested parties got an update on the project from GRE officials. Then they were asked for feedback — pro and con — on providing sufficient crop residue for the biorefinery.

“Our motto is ‘This is where agriculture meets energy,’” said Greg Ridderbusch, GRE vice president of business development and strategy. “This is a partnership with area farmers and can’t get done without it.”

The proposed biorefinery would be a second host for the processed steam produced by Spiritwood Station in making electricity. When it’s up and running, the coal-fired combined heat and power plant will sell steam to its first host, Cargill Malt.

Ridderbusch said the feedstock — wheat straw and corn stover — provided by area farmers is the make-or-break portion of the project. The biorefinery would need to use about 1 million tons of feedstock yearly to produce ethanol, C-5 molasses and lignin.

“It’s a biorefinery with three products, three top revenue streams, not just ethanol,” he said.

Technology on the uses for molasses is still developing, he said, but at the very least it can be fed to farm animals. Lignin is a fuel substitute that Spiritwood Station can burn thereby reducing the amount of coal needed.

“Lignin burns almost as hot as coal and reduces greenhouse gas production,” Ridderbusch said.

Lignin also has a market as a “green” fuel. It can be sold if that’s more profitable.

The production plan for the biorefinery is 40 percent ethanol, 20 percent molasses and 20 percent lignin.

Sandra Broekema, GRE’s manager of business development, heads up the project. She said the biorefinery would use 240,000 pounds of steam per day to process the feedstock. She said Spiritwood Station can produce about 350,000 pounds of steam daily, so there’s plenty for other users.

GRE originally focused on wheat straw as the feedstock. However, studies done by North Dakota State University indicated corn stover along with wheat straw offered a higher yield of biomass.

“It’s good to have a second feedstock source in case of crop failure,” Broekema said. “It also opens a broader harvest window.”

She noted that studies have shown Minnesota and North Dakota are in the heart of biomass country. But to succeed in the biorefinery venture “a cooperative-like approach” with farmers is needed.

Providing feedstock for the biorefinery would require removal of a percentage of corn stalks and wheat straw. NDSU puts the percentage at 25 percent.

“You have to leave a certain amount of crop residue for soil health,” she said.

Mike Saer, GRE’s business development analyst, said in the Danish system, which has 20-plus years of removing wheat straw, the figure is 75 percent. The straw is left standing every fourth year. Inbicon produces cellulosic ethanol in Denmark using wheat straw only. The company is involved in the biorefinery venture here.

PowerStock, also involved in the venture here, is a contractor with 10 years of experience removing crop residue in Oregon. Saer said it removes 50 percent of the crop residue. Show Me Energy in Missouri, which uses biomass to make pellet fuel, removes 65 percent.

None of those enterprises has to travel far to gather biomass, nor are there differing harvest times. For this area, however, Saer said GRE is looking at a “spoke and hub” arrangement for gathering and storing feedstock. Storage would need to be anywhere from 180 days to 365 days, and distances could reach 75 to 100 miles for feedstock collection.

These ideas, including the amount paid to farmers for feedstock and who does the baling and hauling, are just suggestions at this point, Ridderbusch said. They, along with sustainability and crop rotation, need to be decided by the farmers.

“We’re not farmers,” he said. “We want to work with the farming community on this.”

Terry Wanzek, farmer and legislator, said cattle eat biomass and that will be another consideration for farmers, when it comes to getting paid for crop residue, especially wheat straw.

“But if the market is right, you’ll get the straw,” Wanzek said.

Studies continue on using two feedstocks as there’s not enough wheat straw in the delivery range, Broekema said. And discussions with the farming community also need to continue.

“We have to know the straw and corn stover will come,” Ridderbusch said. “We want to listen to your ideas.”

source: jamestownsun