Stephen Gardner, Eddyville, IA, is one of a number of growers with big dreams for switchgrass. The native grass could generate electricity and fuel vehicles while improving marginal lands.
This potential biomass fuel crop, however, has a long row to hoe before it can be profitable for growers, says Bill Belden, biomass project manager for the Chariton Valley Biomass Project. Belden works with Gardner, who is president of Prairie Lands Bio Products Inc., an organization with 60 dedicated grower members.
For nearly a decade, Prairie Lands, the Chariton project and Alliant Energy, Centerville, IA, have invested in and investigated the possibility of co-firing switchgrass with coal to generate electricity.
This past May, a final test burn was completed at Alliant's Ottumwa Generating Station in Chillicothe, and is currently being analyzed. In the next year, if all goes well, Gardner says his group hopes to line up growers in a 70-mile radius to supply the plant with 200,000 tons/year of switchgrass. At 4 tons/acre, 50,000 acres will meet the required 5% of the power plant's energy input needs. The grower group is also asking for farm bill changes to help make the crop attractive — and profitable — for growers.
The past few years, Prairie Lands growers have harvested switchgrass grown on 4,000 acres of CRP land under special USDA permit. The U.S. Department of Energy (DOE) has deemed switchgrass a promising biomass crop to help replace America's dependence on fossil fuels. But it's lacking essential pieces, Belden cautions.
“In my opinion, the co-firing biomass business is probably where the ethanol business was 30 years ago. And the genetic improvements of switchgrass are probably where seed corn was in the 30s and 40s. There have been no economic drivers to grow a hotter-burning switchgrass that yields more tons to the acre,” he says.
Millions of dollars have been spent in recent years to determine how herbaceous crops such as switchgrass can produce fuel, including cellulosic ethanol. Ethanol from switchgrass is five to six times more energy efficient than corn ethanol, says Ken Vogel.
Vogel, a plant breeder with the University of Nebraska, has been working with DOE and the Natural Resources Conservation Service, studying switchgrass. The slow-down in turning the native grass into ethanol, he says, comes from the plant itself. While corn starch easily converts into corn ethanol, the complex cell-wall carbohydrates in switchgrass need cellulosic and hemicellulosic enzymes to break them down. Recently, however, molecular biologists have found ways to cheaply produce these needed enzymes and Vogel is continuing his switchgrass breeding work.
“The problem we had in breeding for improved biomass conversion was that we didn't know what conversion technology was going to be used. We're starting to get an idea of what traits we need to change in switchgrass in order to improve its conversion efficiency,” he says.
“We're also doing work on improving yields and developing technology to produce switchgrass hybrids. We've got some preliminary data that shows you can significantly improve yield by developing hybrids.”
Vogel and colleagues researched the perennial crop's production costs on Nebraska and North and South Dakota fields over a five-year period. Ten growers planted a total of 175 acres of the grass for an average yield of 0.4 ton/acre the establishment year, 2.2 tons/acre the second year and 3.1, 4.2 and 3.5 tons/acre the third, fourth and fifth years.
“The two farmers who had grown switchgrass before had the lowest costs of production. For several reasons, they were able to get harvestable yields the first year. They also were able to get higher yields. This reaffirmed that getting harvestable yields the first year drastically affected the average costs of production over the five years,” Vogel says.
Establishment costs ranged from $35 to $133/acre, he adds.
Gardner, who grows 6 acres of switchgrass on CRP land, agrees that establishment is difficult.
“Switchgrass seed is about the size of pepper. A lot of people frost-seed switchgrass by basically throwing it out on the ground and letting it go. I think they're getting mediocre stands from it. I use my Max harrow, which tills the ground no more than ½-¾" at best. And I have a Brillion cultipacker seeder. We need to try and establish switchgrass with a little more intent, rather than throw it in the wind.”
He also applies glyphosate as a spring burndown. Because switchgrass is a warm-season perennial, it will lie dormant while the herbicide kills off the fast-growing foxtail competition. Switchgrass also stabilizes the soil and, potentially, sequesters carbon, Gardner and Vogel say.
Belden says switchgrass tonnage ranges from 2 tons/acre to up to 8. He would like to see more research on switchgrass. “If you go to any university and ask how to efficiently grow a dedicated biomass product, you're not going to get many answers. We haven't created a formula like we have for growing corn.”
Today, Chariton project members are talking to congressmen about getting farm bill subsidy help.
“We have to look for ways to help the farmer underpin his cost of production,” Belden says. A farm bill change that could possibly transition CRP acres into a dedicated energy crop may help.
“I think we have to make it attractive for the producer to want to step outside of the CRP program and grow an energy crop with an underpinning from the government. And be allowed to manage and harvest it, maximizing its potential,” he says.
“Hopefully, we can lure some of those acres away from CRP into an energy crop system for somebody who believes this is the future of the nation,” Belden says.
Vogel, too, is hopeful. “I think it's going to be a plus for agriculture,” he says. Three companies are gathering funds and looking for locations to build three biomass fuel plants. “That biomass may be wheat straw, corn stover or perennial herbaceous crops.”
What does this mean for growers? “These plants are going to cost about $300 million, some engineers have predicted. For a company to make that big of an investment in an area, it needs to be assured that there is going to be enough feedstock available for a 20- to 30-year period. So, if producers are interested, they need to organize and set up groups to show what can be done in an area.”
The Chariton Valley project, Belden thinks, sets a good example. “I really hope, when it's all said and done, that southeastern Iowa is a shining star because we've done things right; we've taken our time,” he says.
For more on cellulosic biofuels, visit:
Unlocking Bioenergy In Switchgrass
Native Grasses Are Best For Biofuels