Of Cows and Climate

ON A SUBZERO FEBRUARY day, Mark Powell stops his vehicle on the road a few miles outside Prairie du Sac. He’s been explaining that cows actually enjoy the polar weather—and as if to prove it, a frisky group in the barnyard across the road turns toward us and rushes the fence.

As a USDA soil scientist and CALS professor of soil science, Powell is focused on the ground beneath their hooves. A few years ago he led a survey of manure handling on Wisconsin dairy farms. He and his colleagues knew how much cows left behind—about 17 gallons a day—but had only educated guesses about the ultimate environmental impact of barnyard design. In open yards like this, says Powell, they found that 40 to 60 percent of the manure ends up uncollected. “It just stays there,” he says. In the decade since his survey, the manure challenge has only grown, both in Wisconsin and nationwide. Water quality has been the major concern, but air quality and climate change are gaining.

A few minutes later we turn into the 2,006-acre U.S. Dairy Forage Research Center farm, and the talking points all turn to plumbing. There’s an experimental field fitted to track how well nutrients from manure bond to the soil. Parallel to one barn are nine small yards with different surfaces, each monitored to measure gasses emitted and what washes out with the rainwater.

The manure pit is frozen over, but circumnavigating the complex—shared by CALS and the U.S. Department of Agriculture—we arrive at the southern terminus of the barns. Uncharacteristic ventilation ducts adorn the walls and roofline. Inside are four unique stalls that can contain up to four cows each. The manure trough is lined with trays so that each cow’s waste can be set aside for further experiments. When the cows return from the milking parlor, airtight curtains will drop, isolating each chamber.

Class Act: Energizing the Classroom

When biochemistry senior Hong-En Chen first got involved with a student organization called Energy Hub, she knew she could bring something special to the table.

As the daughter of a preschool teacher, she’d interacted a lot with young children throughout her own childhood and adolescence. While in high school she worked as a teacher and tutor in music, math and reading in both English and Mandarin at the Einstein School in Madison, a private preschool and after-school enrichment center for elementary school students.

Based on her experience, she saw an important niche for Energy Hub: The group could go out to local elementary schools and hold after-school classes about energy.

“When kids are young, they’re like sponges. They absorb a lot of information and are enthusiastic learners,” notes Chen. “When we introduced concepts about energy use, conservation and sustainability, the kids impressed us not only by handling complex material, but also by applying ideas to their everyday lives.”

As outreach director of Energy Hub, Chen got other club members on board to pilot their project, working with second- to fifth-grade students at four Madison elementary schools. Based on that experience, they applied for and received a Wisconsin Idea Fellowship grant to further develop their curriculum during the 2012–2013 school year. They created a 10-week program that is going strong this year.

Hands-on activities are key, says Chen, whether using an educational science toy like Snap Circuits to teach the concepts behind powering lights and fans, or having students divide into the fantasy cities of Greenville and Coaltown to talk about how they, as residents, would use energy from various sources to get through a day. “It was a fun way to get them thinking about the costs and benefits of renewable versus nonrenewable energy sources,” Chen says.

Chen’s thinking a lot about that topic herself. She is researching compounds for solar energy conversion in chemistry professor Song Jin’s lab. And she is considering graduate programs in materials chemistry with an eye toward working in renewable energy research.

Learn more about Energy Hub at www.uwehub.org.

Wisconsin’s “Brown Gold” Rush

Earth’s petroleum stores are dwindling, but a Wisconsin project aims to produce energy from a resource that’s in little danger of running low: cow manure, or “brown gold.”

The University of Wisconsin–Madison and several state companies, funded by a $7 million grant from the USDA Biomass Research and Development Initiative (BRDI), have partnered to pilot the conversion of dairy farm manure into useful product streams—a project that is expected to have significant environmental and economic benefits.

The Accelerated Renewable Energy (ARE) project is in progress at the 5,000-cow Maple Leaf Dairy in Manitowoc County, where animal waste is separated into different streams, or fractions, of processed manure.

After small plant fibers in the manure are separated and anaerobically digested to biogas, liquids from the digestion process are used to fertilize crops, while solids can be converted into useful chemicals and bio-plastics. Larger plant fibers make great animal bedding and mulch, not to mention a starting material for ethanol fermentation.

Meanwhile, at the new Wisconsin Energy Institute at UW–Madison, project co-investigator Troy Runge, a CALS professor of biological systems engineering, is analyzing the ARE project’s separation techniques to improve their efficiency. “We are performing many of the same separations that occur on the farm, but in the controlled environment of
the lab to both measure and optimize the system,” says Runge.

Tom Cox, a project collaborator and a CALS professor of agricultural economics, sees great potential for the initiative. “This is a triple-win situation; we would like to make money by doing the right thing by the environment and society,” he says.

Aicardo Roa-Espinosa MS’85 PhD’89, president of partner SoilNet LLC and an adjunct faculty member in biological systems engineering, developed the manure separation technology behind the project. Roa-Espinosa and Runge will monitor the quality, quantity and composition of biogas produced and analyze processed manure streams to identify chemical constituents. Student researchers will conduct life cycle assessments to evaluate the project’s environmental impact.

The goal for the four-year grant, researchers say, is to improve these manure separation technologies until their sustainability benefits can be realized on a broader commercial scale.

Runge notes that the public-private, multidisciplinary project exemplifies what the university hopes to do with the Wisconsin Energy Institute. “It’s also an example of a project that’s important to Wisconsin,” he says.

Indeed, the project may help farmers manage manure with benefits for both the environment and human health. A 5,000-cow dairy farm like Maple Leaf produces approximately 25 tons of manure per day, which require millions of gallons of water to manage. Although some manure may be used as fertilizer, nutrient imbalances and runoff can create environmental problems. However, manure processed using SoilNet’s technology yields concentrated, homogenized fertilizer that can be applied with greater control over nutrient content.

In addition to its environmental benefits, the cellulosic—or non-food—plant biomass derived from dairy manure avoids the conflict of “food versus fuel.”

That’s a promising basis for exciting innovations at dairy farms. For ARE project leaders, farms are not only the heart of agriculture. They also have the potential to serve as foundations for cellulosic biorefineries that could prove key in supporting a local green economy and a sustainable energy system throughout the region.

Biofuel for Teens

As students in Craig Kohn’s class at Waterford Union High School can tell you, you don’t need a grant or Ph.D. to do scientific research. A question and some curiosity are all that’s needed—along with a sturdy pair of gloves.

Kohn BS’08, who earned degrees in biology and agricultural education at CALS, teaches a class called Biotechnology and Biofuels in which students hunt for bacteria that naturally secrete enzymes called cellulases. Cellulases are named for their ability to break down cellulose, the sugar polymer in plant cell walls that gives stems and leaves their structure.

“Cellulases are important for bioenergy because they are necessary to turn cellulose into a fermentable product that can be made into ethanol and other biofuels,” says Kohn.

To find those cellulase-producing bacteria, Kohn sends students out to collect samples from the compost heaps and animal pens behind their school in a quest known as “bioprospecting.”

Back in the classroom, students drop the samples into test tubes filled with media solution and a strip of filter paper. If cellulases are present, the cellulose-based paper will disintegrate as the enzymes do their work.

That process of discovery excites students. “You see this light in their eyes when they realize that they are participating in science directly, and that their work could lead to actual breakthroughs and results,” Kohn says.

Kohn developed the activity as a participant in “Research Experience for Teachers,” a program at the UW’s Great Lakes Bioenergy Research Center (GLBRC). For his project he shadowed Cameron Currie, a CALS professor of bacteriology and a GLBRC researcher who uses genomic and ecological approaches to study biomass-degrading microbes.

“Teachers are not only learning about current science—they are embedded in the lab,” says John Greenler, GLBRC’s director of education and outreach. “When teachers have that primary experience, they are in a better position to engage their students because they ‘get it.’”

Connor Williams, a high school senior who helped develop the bioprospecting lab with Kohn through his participation in the National FFA Organization (formerly Future Farmers of America), says his favorite element is the hands-on, independent work.

“I learned that answers to biofuel challenges literally can be found right in our backyards,” Williams says. “You just need to know where to look.”

“Red Barns” Go Green

Lofty red barns may be Wisconsin icons, but the real workhorse structure in agriculture today is the post-frame building. You can’t drive very far down a rural road without spotting one being used to house livestock, store and repair equipment, shelter hay or myriad other uses. Virtually every new structure on a modern farm gets built this way, and with good reason. Post-frame buildings are versatile, easy to assemble and affordable.

And now they’re becoming more sustainable, thanks to a “Green Frame” building system being developed by Dave Bohnhoff, a CALS professor of biological systems engineering.

Unlike traditional post-frame construction, Bohnhoff’s system isn’t based on preservative-treated wooden posts embedded into the ground. He uses non-treated wooden “I-posts” affixed to precast concrete piers. The I-posts are sandwiches of dimension lumber and laminated-strand lumber that are structurally and thermally more efficient than timber posts. Another sustainability feature relates to how the frame parts go together. The frame members that tie and brace the vertical posts and roof trusses have reinforced, deep notches at the ends that mate with adjoining pieces. This makes assembly easier, safer and more accurate. It also makes it easy to disassemble and reuse the components when a building outlives its usefulness as the farm enterprise grows and evolves.

Will all of those non-standard parts drive up the cost? Not at all, says Bohnhoff. The beams, connecting pieces and concrete piers can be fabricated on site using materials available in most lumberyards, tools found in any farm shop and basic construction skills.

 

The Inner Lives of Cows

What do biofuels look like on the Wisconsin landscape? Some might think of corn or switchgrass. But what about that herd of cows?

What you can’t see might fool you. Cows are walking natural biodigesters, says CALS bacteriology professor Garret Suen. Their rumens are filled with rich bacterial communities that break down the cellulose found in feed into nutrients usable by the animal.

“The cow is arguably one of the most efficient cellulose degraders around, and the main reason why is that we’ve domesticated them to be that way through selection,” Suen explains. “What I argue is that we didn’t just domesticate the cow, we domesticated their microbes.”

Efficiently breaking down cellulose into simpler usable materials—a key challenge in biofuel production—is a feat naturally performed primarily by microbes. “A cow couldn’t exist without its bacteria, because it has no way on its own to break down the plants that it eats,” he says.

Suen, a researcher with the Wisconsin Bioenergy Initiative, is exploring the workings of the ruminant system in the hope of harnessing its power for industrial applications. He’s focusing on three strains of bacteria in the rumen that use different strategies to degrade cellulose. Drawing upon his background in both computational biology and genomics, Suen is using next-generation sequencing to hone in on the individual genes, enzymes and other proteins used by each and how they work together.

“Understanding the different ways that nature has come up with to degrade recalcitrant plant material will be very useful,” he says.

To date, Suen’s research group has identified some sets of genes they believe are involved, including some interesting surprises that he isn’t quite ready to share. He recently received a five-year, $750,000 early career award from the U.S. Department of Energy to advance the project. Suen hopes the work could ultimately extend even beyond bioenergy.

“Understanding how the microbes are breaking down these plant biomasses doesn’t only impact biofuels. It also has implications for areas like improving digestibility of feed and nutrient yield for the cow—which could directly affect everything from milk production to feed costs to beef quality,” he says.

Sustainable by Design

THE CHILDREN’S SONG URGES HER TO FLY AWAY HOME, but the ladybug—or ladybeetle, as she’s properly called—is anything but a homebody. After feasting all summer on soybean aphids and other crop pests, the beetles take off from farm fields in search of snug overwintering spots, often winding up in people’s houses. Around Madison, this usually means a journey of five miles or more, says CALS entomology professor Claudio Gratton. But the insects can also fly much farther. In the Southwest, for example, they congregate on mountaintops. “You’ll come upon a bush just dripping with ladybeetles, and you know they probably had to travel 30 miles to get there,” says Tim Meehan, a research scientist working with Gratton who earned his doctorate in
New Mexico.

Those wandering ways got Gratton and Meehan wondering a few years back if the beetles’ lives were touched not just by the soybean fields where they fed, but by the wider world as well. They soon discovered that, indeed, “What the landscape looks like actually makes a big difference,” says Gratton. In experiments across the Midwest, ladybeetles devoured more aphids in fields nestled within a patchwork of woods and grassy pastures than in those surrounded by soybeans and corn as far as a bug’s eye could see.

Although the two still aren’t sure why this is, it led them to ponder another possibility that has big implications for the sustainability of our farmlands. If the chance variation that exists in some farming areas already gives ladybeetles a boost, what if farmlands were purposely designed for diversity? Would the insects dispatch even more aphids? Might they even become tiny tools of sustainability, allowing farmers to spray fewer chemicals?

It takes a lot of imagination to picture such a landscape today, with two-thirds of the Midwest’s cropland blanketed in corn and soybeans. But there is a force that could re-stitch the Corn Belt into a crazy quilt—the push toward ethanol and other types of bioenergy. True, the ethanol blended into gasoline today still comes exclusively from corn kernels. And few “dedicated” bioenergy crops, such as grasses, have been sown so far for making cellulosic ethanol from stalks and stems, or burning in power plants instead of coal.

But bioenergy crops will almost certainly grow widely one day. The goal of the U.S. Department of Energy (DOE) is to replace 30 percent of gasoline and other U.S. transportation fuels with biofuels by 2030. And that, CALS scientists say, offers a chance to reshape our farmlands in an unprecedented way, so they yield not only food and fuel, but also things like ladybeetles and the benefits they provide.

In scientific parlance those benefits are called “ecosystem services”—natural processes we rely on but don’t usually pay for, Meehan says. Pest control by ladybeetles is one service; pollination by native bees, water cleansing, soil formation and even aesthetic beauty are others. Today’s simplified agricultural landscapes excel at producing corn, cotton and other vital commodities in massive amounts, but these may come at the price of water quality, erosion, loss of bird and insect habitat and increased pesticide use, as another study by Meehan and Gratton recently found. The question now is whether switchgrass, willow and other biofuel crops could cut those costs by sowing some plant diversity back into the system.

“The focus now is land use, not just food or fuel or a new crop. How do we use land sustainably?” says Chris Kucharik, a CALS professor of agronomy and environmental studies. “It just so happens that fuel has ignited the debate over sustainable land use right now.”

At the same time, strong forces are working to maintain the status quo. Skyrocketing commodity prices and rising demand for ethanol have led many farmers to put as much land in corn as possible. This year, 92.3 million acres were planted, according to the U.S. Department of Agriculture, four million above last year’s total and the second highest amount since World War II.

Where Are We Now?

TIM DONOHUE HAS SPENT THE LAST FOUR YEARS BUILDING A PIPELINE—but not the kind that springs to mind when we think of fuel.

The professor of bacteriology heads the CALS-led Great Lakes Bioenergy Research Center (GLBRC), founded with $142 million from the U.S. Department of Energy and a groundbreaking charge—to create the next generation of biofuels by harnessing renewable energy from the nonfood plants that are so plentiful all around us: grasses, trees and crop residues.

“We need to create liquid transportation fuels that are more cost-effective, more sustainable and won’t compromise the Earth or our quality of life,” says Donohue. “We’re in the middle of developing ways to generate these new fuels that are essential for powering our daily lives.”

With Michigan State University (MSU) as UW–Madison’s major partner, Donohue has assembled a team that now includes more than 400 researchers and staff and an additional nine member institutions. The effort spans two countries, 11 states and more than 60 individual lab and field facilities.

That’s a lot of brainpower. But the magnitude of the effort is commensurate with the task at hand, Donohue notes.

“We need to be considering everything from roots in the ground to what’s coming out of the nozzle,” Donohue says. “Without such a holistic approach, we won’t be able to demonstrate that this technology is feasible or see the weak spots where we can make improvements.”

What GLBRC has built is a research pipeline, a process that considers all factors that go into developing and implementing cellulosic biofuels—from creating sustainable agricultural landscapes and building better bioenergy crops to innovations in plant biomass processing and converting plant sugars into fuels.

While the promise of creating sustainable plant-based fuels isn’t new, the level of public investment needed to tackle this challenge has only recently emerged. According to the International Energy Agency, the United States leads world spending on biofuels public research, development and demonstration projects, investing $189 million in 2010 alone.

“By relying on fossils fuels, we’re living on energy that arrived on Earth many millions of years ago,” says Steve Slater, GLBRC’s scientific programs manager. “In order to reach a sustainable energy economy, we need to learn to live on the energy that arrives from the sun today. There’s a lot of that solar energy held within plant biomass, if we can figure out how to sustainably convert it to liquid fuels.”

Four years into its five-year grant, GLBRC has made some significant breakthroughs along the research pipeline. Here are some major points of interest.

First Stop: PLANTS

At agricultural research stations in Wisconsin and Michigan, GLBRC researchers tend to tall stands of such biofuel crops as switchgrass and miscanthus, measuring above-ground traits like crop yield and digging down in the dirt to monitor soil microbes and water movement. Sophisticated instruments measure greenhouse gases such as carbon dioxide and nitrous oxide. Researchers count birds and insects to measure biodiversity and use satellite data to capture a watershed-level view of land use patterns.

It’s a lot of information, but each measurement plays a role in determining how these crop contenders would fare as large-scale bioenergy crops.

The leaves and stalks of these potential bioenergy plants are comprised of large quantities of cellulose, the most abundant organic compound on the planet. Cellulose is a polysaccharide, a long chain of tightly linked sugar subunits that must be broken down into simple sugars before they can be processed into biofuel. That alone is difficult—but to make the process even harder, much of a plant’s cellulose is locked within cell walls that form a tough, protective barrier. Breaking past the walls, using enzymes or chemicals to do so, is one of the biggest challenges in creating economically viable cellulosic biofuels.

Plant cell wall structures have evolved over time to fight off pests and disease. The more scientists understand about how the walls are created, the easier it will be to break them apart. DNA sequencing capacity provided by the Department of Energy (DOE) Joint Genome Institute allows plant breeders access to genetic and genomic data that provide clues about how those cell wall layers are built.

While determining the best genetic traits for bioenergy crops is a long-range goal, GLBRC plant researchers already have made important headway when it comes to tackling lignin, one of the toughest compounds that make up plant cell walls. Researchers hope to take it apart to get at the cellulose locked inside and convert small pieces of lignin into valuable co-products. CALS biochemistry professor John Ralph and his team have identified a gene that would allow easily breakable bonds to be incorporated into plant cell walls. They’re calling this new technology Zip-Lignin™ for its ability to break apart—or unzip—the lignin within. By getting lignin out of the way, biomass processing could be completed at lower temperatures. And lower temperatures mean lower overall costs.

And on another track, GLBRC researchers at MSU have located an enzyme that creates a plant oil with unique biodiesel-like properties. Now they’re working to encourage plants to produce more of that oil, which could be used directly as a “drop-in” or ready-to-use diesel replacement.

Beyond the Gas Tank

ON TIM BAYE’S LIST OF WISCONSIN BIOMASS-BASED PRODUCTS, LIPSTICK looms larger than ethanol.

“One of the most attractive markets this year is a paraffin derivative for lipstick use made from bio-based materials,”
says Baye, a UW–Extension professor of business development who specializes in bioenergy consulting and executive
education.

“The bio-based chemical market is appealing because you get a better return on a more modest amount of feedstock compared to fuels,” he says. “The markets are not as volatile as they are for liquid fuels, and we don’t need major infrastructure, such as pipelines, to move the stuff. We can do it by truck and train.”

Baye has been crunching numbers on bioenergy projects for 27 years, both in his current job and in several private sector positions, including a two-year stint leading an initiative to start up an ethanol plant. Since the mid-1990s he’s also been experimenting with growing biofuel crops—switchgrass, sorghum, aspen and mixed grass stands—on a 240-acre farm in Woodman.

Asked what he thinks Wisconsin will be doing with biomass in the future, he quickly ticks off a dozen projects that already are operating or are on the drawing boards. The tally includes electrical plants fueled by everything from old railroad ties to landfill waste to willow, paper mills that have branched into wood pellets and biodiesel, and municipalities making biogas and fertilizer
from wastewater.

Notably lower on his list: corn-based and cellulosic ethanol.

“We’ll continue to produce liquid fuels from biomass, including corn, as long as the margins are justifiable,” Baye says. “But we don’t have the long growing season they have down South and in the tropics. That’s where you have higher biomass growth rates and yields, and that’s where we’re likely to see most of the biomass-based liquid fuels produced.”

What he does expect to see are lots of multipurpose facilities, where firms supplement their core business with energy and other biomass-based products in order to diversify, cut costs, spur revenues and make use of industrial residues. He cites the paper industry as a prime example.

“A number of our paper plants are planning on bolting on technology platforms to allow them to produce products other than paper,” he says. “A pulp tree may still go to the paper plant, but be converted to something much different than paper.”

He points to a Wisconsin paper mill, Flambeau River Papers, and its planned sister facility, Flambeau River BioFuels, as a national leader. Flambeau River Papers is refining its residual, pulp liquor—a rich red-brown broth left over from the paper-making process—into such value-added products as xylitol, used in making sugar-free gum, and into a binder used for dust control on dirt roads. The paper mill is powered by a biomass-fueled boiler. Flambeau River Biofuels plans on producing biodiesel and industrial lubricants and waxes in a facility scheduled to begin construction in 2012.

This strategy isn’t limited to paper plants. Corn-based ethanol plants are also considering adding processes to improve performance and diversify. Some of the first cellulosic ethanol plants have taken this approach and are eyeing the chemical market too.

Baye also expects to see more biogas digesters—producing methane and generating power and heat—coupled with municipal waste treatment plants to deal with wastewater and industrial residuals laden with organic content from food processors and other manufacturers.

“Municipalities are under pressure to upgrade these plants, which means higher charges,” Baye says. “To minimize these upgrades, they will look to divert the organic material and get a little gift back in the form of biogas. And there are a number of opportunities for them to produce additional, high value products—especially fertilizers.” New regulations addressing phosphorus management will likely accelerate this trend.

Baye says that many such projects will require partnerships between municipalities, local industries and farmers, who will grow switchgrass, sorghum and other bioenergy crops as additional feedstock for the digesters.

And even if Wisconsin doesn’t lead the pack in ethanol production, Baye thinks the Badger State will benefit from any growth in the ethanol industry. The expertise acquired making paper, beer, silage and cheese transfers nicely to the bioenergy business, and it’s a marketable product in and of itself, he points out.

“In the future we probably will be buying cellulosic fuel from other regions, but we’ll be selling them chemicals and enzymes and vats and pumps, technology, legal services and know-how,” Baye says.

Cash Crop Biomass

WISCONSIN FARMERS have been growing biomass for generations, says Kevin Shinners. They just have a different name for it.

“Biomass is really just poor-quality forage,” says the CALS agricultural engineer. “We allow it to get very mature and it’s really high in fiber, so it doesn’t make very good animal feed, but it
makes great biomass.”

And Wisconsin farmers have a leg up in the business of producing biomass, says Shinners, a specialist in forage systems who branched out into bioenergy crops about 10 years ago.

“We have all of the tools to harvest and handle and process it. And an added advantage is that when we take biomass off the field, we have new places to put our dairy manure,” he says. “When you take corn stover off the field, you’re
removing nutrients that you need for next year’s crop. A Wisconsin farmer can apply manure, while an Illinois farmer may have to go out and buy fertilizer.”

Wisconsin also is rich in off-farm resources. The state’s custom harvesters are expert at chopping stalks and grass, and biomass could fit nicely into their schedule. After they finish chopping corn silage in September, crews could move on to corn stover or switchgrass in October and November, spreading fixed costs over more acres and keeping employees working longer.

In fact, under some business models, farmers might job out most of their biomass crop production. If the crop is a perennial, such as switchgrass, the farmer may spend more time in front of the computer and on the phone than out in the field. “Once the crop is established, he’ll manage fertilization and weed control through an agronomic service, cutting and removal through a custom harvester and marketing through a biomass aggregator,” Shinners says.

But even though Wisconsin farmers may be very much at home with the types of crops involved and the mechanics of producing them, they’ll be on less familiar ground when it comes to marketing, Shinners notes.

“If you’re a cash crop farmer, you’re used to marketing your corn and beans through multiple paths, selling some out of the field, storing some, selling futures, to optimize what you earn on an annual basis,” he says. “For biomass, you’ll have to change your mindset.

“If a firm builds a large cellulosic biorefinery here, it will need an absolute dedicated supply,” Shinners says. “If half the people in the area decided not to produce biomass one year, that plant would be a dinosaur.” Meaning that a critical mass of local farmers must be willing to lock into a long-term production contract.

The economics of biomass are driven by the fact that, pound for pound, the stuff isn’t worth as much as other crops. Profit margins may be slim, so farmers will need to produce as efficiently as possible.

That’s where Shinners comes in. His research centers on streamlining the harvest and handling a variety of biomass crops, including such perennials as switchgrass and reed canarygrass, and annuals such as sorghum. But his biggest push has been in corn stover—the stalks and leaves and cobs left when the kernels are removed—simply because there’s so much of it.

“There are some 90 million acres of corn being grown in the United States this year, and with the prices we’re seeing, there’s going to be more and more of it grown. If you’re really interested in biomass, it’s right there at our doorstep,” he reasons.

Since profit-minded crop producers aim to make as few trips across the field as possible, Shinners’ first efforts focused on harvesting both corn grain and corn stover in one pass. Essentially, he grafted a forage harvester to the back of a combine and hitched a wagon behind to catch the chopped stover.

This impressive 50-foot train of machinery worked, he says, but handling two crops at the same time slowed down the grain harvest, putting both yield and quality at risk. “That’s even more of an issue these days, when we have seen corn go over $7 per bushel,” he says. “As corn grain increases in value, everything that slows the combine down has a much greater economic cost.”

Shinners is focusing now on a system in which the combine harvests grain and leaves the stover behind in a long, neat row. “A custom harvester could come in behind and chop these windrows and store them for the farmer.”

Since buyers will need year-round deliveries, storing biomass crop until it’s needed is part of the equation. Shinners thinks the best approach is one that dairy farmers use for forage—seal it from the air in long plastic bags or covered bunkers and let it ferment. “We know this from dairying: You can open up a silo bag from two years ago and it’s still good quality,” he says.

That fermented biomass could be good enough to eat—by livestock, at least—which may offer farmers a way to take advantage of the bioenergy market without having to wait for a biomass refinery to be built nearby.

“If we apply amendments like lime right before we store corn stover, the feed value can increase substantially,” says Shinners. “So instead of waiting for somebody to develop a biorefinery in Wisconsin to convert stover to ethanol, why not divert some of the grain normally used to feed cattle toward ethanol production and use the stover to replace the corn as animal feed?”

From Field to Fuel

Where are we in terms of moving toward the “green gas” of the future?

The Great Lakes Bioenergy Research Center, led by CALS with Michigan State University as a major partner, has over the past four years been conducting basic research to convert non-edible plants such as grasses and trees to ethanol and other advanced biofuels. Here we present an overview of research progress.

 

O Bioneers

It wasn’t exactly panning for gold, but a lesson in “bioprospecting,” as it’s called, had students scour the campus looking for something just as valuable: invisible forms of life that could one day be key in developing a sustainable alternative to oil.

“Instead of going out and looking for precious metals, we’re looking for precious microbes,” says John Greenler, director of education and outreach at the Great Lakes Bioenergy Research Center and lead instructor of the university’s first bioenergy course for freshmen, held this past fall semester.

“Out in the environment there are a lot of microorganisms that are really good at breaking down fibrous plant material,” Greenler notes—a vexing but essential step in producing biofuel.

“Before I took this class I was only a little curious with the concept of bioenergy. Now I feel involved with bioenergy research and the possibility of using it to solve many environmental, political, and economic problems.” -Michael Polkoff

“We’re hoping to figure out how those microbes do that and then utilize that process to make biofuels—essentially, capture energy for our transportation needs the same way the microbes capture energy as a source of food,” Greenler says.

“Bioenergy: Sustainability, Opportunities and Challenges” debuted as a First-Year Interest Group (FIG) program open to 20 freshmen, and it was snapped up quickly during registration. As the bioprospecting lab shows, the course was designed to have students work on real-world problems researchers face in a new and rapidly growing field.

That includes the frustrations. Student Michael Polkoff reports that the prospecting material chosen by his group—pond scum—came up negative for microbes that produce cellulose-busting enzymes.

“While the results are depressing for the work we put into this—especially going barefoot into a freezing, sludgy drainage pond—it’s part of doing scientific research,” says Polkoff. “Sometimes you get results, other times you don’t. More importantly, we learned how research is done.”

The course has galvanized Polkoff’s interest in bioenergy. “Before I took this class I was only a little curious with the concept of bioenergy,” he says. “Now I feel involved with bioenergy research and the possibility of using it to solve many environmental, political, and economic problems.”

The course is offered through a partnership between the Great Lakes Bioenergy Research Center and the Wisconsin Bioenergy Initiative. Students visit the UW campus labs of some of the nation’s foremost researchers, and one field trip took them to CALS’ Arlington Research Station to study bioenergy field plots.

The FIG program, which clusters three courses linked by a common theme—the bioenergy course was paired with introductory chemistry and environmental studies—targets low income, minority, “first in family to college students,” says Greenler. “Overall, about 30 percent of students in the FIG program are minorities.”