Biofuels bolster state's energy outlook

Friday, March 14, 2008

Revitalizing rural areas will strengthen Oklahoma’s energy industry.

(March 14, 2008   Stillwater, OK) - An interdisciplinary team at Oklahoma State University and cooperating institutions stands to potentially revitalize rural areas in Oklahoma and beyond by creating new ethanol production practices that will enhance and strengthen the state’s multi-billion-dollar energy industry.

Ray Huhnke, OSU Division of Agricultural Sciences and Natural Resources (DASNR) agricultural engineer and coordinator of the university’s biofuels team, says the entire OSU approach is unique, with an emphasis given toward achieving economical conversion of crop residues and grasses to ethanol.

“The beauty of the OSU system is that for every 1 unit of energy put into the ‘grassohol’ process, as much as 3 units of energy are returned,” Huhnke says. “Traditional corn-based ethanol production provides about 1.6 units of energy per 1 unit of energy input.”

Instead of looking solely at corn, OSU Biofuels Team researchers are studying all types of perennial grasses and even straw.

“We are considering all these types not only to ensure they work well but are available in the necessary volume throughout the year because bioconversion must be a year-round process to be economically viable,” Huhnke says. “In addition, we are evaluating grasses on the basis of how they affect the environment in terms of nutrient needs and wind and water erosion.”

It is hoped that the grasses and residues will provide more than 60 gallons of ethanol per dry ton of material.

“I like to tell people that if you see a round bale in a field, consider that single bale to be a barrel of liquid fuel,” Huhnke says.

In OSU research tests, biomass is combusted in a device called a gasifier, where plant components – cellulose, hemicellulose, and lignin – are turned into a gaseous state composed primarily of carbon monoxide, carbon dioxide, and hydrogen. The gas then flows through a cleaning and cooling system and then into a bioreactor where it is microbially turned into a mixture of ethanol, inert gases, water, and other useful products. The mixture then is processed still further, separating and recovering the essential products, including ethanol that is then distilled into a fuel-grade product.

The OSU Biofuels Team of investigators working on the creation of economically viable ethanol from Oklahoma biomass include professionals from DASNR, the OSU School of Chemical Engineering, the University of Oklahoma, Mississippi State University, and Brigham Young University.

Days of future past

OSU’s groundbreaking research on turning grasses into energy has been receiving a lot of attention, from Congress and the White House to the Oklahoma Governor’s Conference on Biofuels and beyond.

“We’ve been very popular with the media, political, and commodity groups, and even people sitting in coffee shops, and for a very good reason; turning biomass into biofuels is not a fad with us, we’ve been committed to these efforts for a long time,” says Robert E. Whitson, DASNR dean and director and vice president of agricultural programs at OSU.

One of OSU’s earliest and most high-profile efforts – turning switchgrass into “grassohol” – received increased public attention after President George Bush mentioned switchgrass in his 2006 State of the Union address, as part of his setting a lofty goal for the nation: Replace more than 75 percent of America’s oil exports from the Middle East by 2025.

“The president’s mention of switchgrass put a greater emphasis on renewable energy beyond standard corn fermentation in providing ethanol to the liquid fuel offerings,” Huhnke says.

Instead of looking solely at corn, OSU researchers have long been studying all types of perennial grasses, including switchgrass.

Oklahoma has thousands of acres of marginal land that is not suited for producing cultivated crops. Yet switchgrass is a resource that such land can and does produce almost naturally. There is no real market for switchgrass in and of itself, but turn that product into ethanol, sell it as an alternative fuel, and the potential is enormous.

“That type of major boost to the economy from a proven environmentally friendly product would benefit Oklahoma, the region, and the nation,” Whitson says.  

Realizing that fact from the get-go, DASNR researchers spent years breeding switchgrass that can produce greater yields. Charles Taliaferro, a longtime Regents professor in the Department of Plant and Soil Sciences who retired last year, used a grant from the Lockheed-Martin Corporation to begin the process of switchgrass improvement in the early 1990s.

The grant was part of the U.S. Department of Energy’s National Biofuels Feedstock Development Program administered by Lockheed-Martin at the Oak Ridge National Laboratory in Tennessee.

From the start Taliaferro, nationally renowned in plant breeding circles, and his fellow researchers recognized the potential of switchgrass, a perennial plant that did not require the amount of nurturing required with row crops. The switchgrass research plots grown as part of Oklahoma Agricultural Experiment Station studies resulted in improved varieties and germplasm used in subsequent plant breeding and other scientific investigations.

Switchgrass is found in the central and eastern portion of the United States from the Gulf Coast to Canada. Switchgrass grows on many different soil types, from bottomland to less productive upland soils. The wide distribution of the species is a plus, because strains can be found growing under a variety of environmental conditions, meaning it can be widely planted and cultivated, with little by way of labor and upkeep relative to other perennial grass species.

Still, the OSU Biofuels Team was careful not to overlook other potential prospects. Different types of grasses must not only work well, they must be available in the necessary volume throughout the year to ensure bioconversion is economically viable.

“Think of it as a continuation of the process started years ago,” Whitson says. “Our OSU researchers didn’t overlook the potential of switchgrass then, which is a prime reason why the science on a national level has developed to the point it has today. Our current, interdisciplinary team of scientists is not concentrating solely on switchgrass just because it’s a hot topic of conversation at the moment.”

Statewide success through local action

One particularly promising aspect of OSU’s biofuels research is the team’s ongoing study of sweet sorghum, with the aim of making possible the effective production of ethanol in the farmer’s own field.

Sweet sorghum can be grown throughout temperate climate zones of the United States, including Oklahoma. It provides high biomass yield with low irrigation and fertilizer requirements. Corn ethanol, in contrast, requires significant amounts of water for growing and processing. Best of all, producing ethanol from sweet sorghum is relatively easy.

“Just press the juice from the stalk, add yeast, allow fermentation to take place, and you have ethanol,” says Dani Bellmer, a biosystems engineer with DASNR’s Robert M. Kerr Food and Agricultural Products Center (FAPC). “Unfortunately, the simple sugars derived from sweet sorghum have to be fermented immediately.”

Throw in the expense of constructing and operating a central processing facility that would only operate the four to five months of the year when sorghum would be available in Oklahoma and the challenge multiplies.

The beginnings of a possible solution presented itself when entrepreneur Lee McClune, president of Sorganol Production Co. Inc., approached FAPC scientists seeking their assistance in testing his newly designed field harvester capable of pressing and collecting juice from sweet sorghum. His proposed Sorganol process involved using the harvester, large storage bladders for fermentation, and a mobile distillation unit for ethanol purification. FAPC and DASNR’s initial involvement in the project was to look at the feasibility of fermenting the juice in the field.

“We’re examining such things as juice extraction efficiency, whether or not pH (acidity) or nutrient adjustment of the juice is needed, and various environmental factors,” Bellmer says.

The goal of the Sweet Sorghum Ethanol Unit of the OSU Biofuels Team is to make production of ethanol from sweet sorghum economically viable by using an in-field processing system that minimizes transportation costs and capital investment.

Equipment such as the harvester and other technology could be owned individually or cooperatively with a number of producers sharing and possibly helping one another process ethanol from sweet sorghum.

In Oklahoma, the potential processing scenario might look like this: Plant sweet sorghum around mid-April, and then stagger plantings for two to three months. This would provide a harvest window of August through November.

“Ethanol yields in Oklahoma could range from 300 gallons to 600 gallons per acre, depending on biomass yield, sugar content, and juice expression efficiency,” says Chad Godsey, biofuels team member and OSU Cooperative Extension cropping systems specialist with the Department of Plant and Soil Sciences.

Godsey says the team is working to determine the maximum possible harvest window for sweet sorghum in Oklahoma.

“Obviously, the longer the harvest window, the more ethanol state farmers will be able to produce,” he says.

OSU Biofuels Team researchers also are studying environmental parameters that may affect the feasibility of on-farm fermentation. A producer must be able to ferment the juice in the field during Oklahoma’s harvest season for sweet sorghum, which occurs in the fall when temperature extremes are highly possible. Temperature can speed up, slow down, or derail the fermentation process.

Weather data for Oklahoma indicate an average low temperature of about 44 degrees Fahrenheit and an average high temperature of approximately 98 degrees Fahrenheit during the August-through-October period over the past 10 years.

Six test plot sites are maintained at Oklahoma Agricultural Experiment Station facilities across the state, allowing OSU Biofuels Team members to conduct research on sweet sorghum under local conditions.

“We would like to do with sweet sorghum what the Brazilians have done with sugar cane: In Brazil, sugar cane ethanol provides a large percentage of their fuel needs,” Bellmer says.

The idea of using sweet sorghum for commercial ethanol production is not new. The reason sweet sorghum is not as popular as corn in terms of being a source of ethanol in the United States has been the need to ferment its simple sugars immediately and the high costs associated with a central processing plant that is operated only seasonally.

“By determining a process by which agricultural producers can create ethanol in the field from sweet sorghum, that barrier is removed,” Bellmer says. “Producers will then have a much higher value product to sell.”

Formula for sustainable success

To take full advantage of the environmental and economic potential of biobased energy, Huhnke believes Oklahoma must develop and invest in ways to produce biofuels that do not negatively affect food, feed, and fiber needs that rely on the production of agricultural crops.

“Evaluating the best types of biomass to grow, the best conversion processes to use, and the best places to locate conversion facilities are necessary if Oklahoma and the nation is to create an industry that is successful and sustainable,” Huhnke says.

Perennial prairie grasses like those in Oklahoma produce less erosion because the plants root well, are not tilled, and generally need little or no fertilizer.

Other states have a vigorous biofuels industry that is dependent on corn to produce starch-based ethanol. Corn lacks the spreading roots that help perennial grasses hold soil and planting corn generally is performed using soil-loosening tilling practices to allow seeds to sprout more efficiently. Corn is also valuable food for humans and livestock.

In the past year, the rush to meet corn-based ethanol demand has contributed to higher feed grain prices for livestock producers and rising food prices for consumers nationwide, despite the fact that American farmers collectively planted an extra 14 million acres of corn this year, an area equal to approximately one-third the size of Oklahoma.

The National Research Council (NRC), the top science review board in the United States, released a report this fall that warns “the increase in harm to water quality could be considerable” if the nation continues to expand corn-based ethanol production without appropriate environmental protection policies. According to the NRC, the results are likely to be more soil erosion, increased levels of pesticides and herbicides in waterways, more low-oxygen “dead zones” from fertilizer runoff, and water shortages for drinking and irrigation.

“Our OSU Biofuels Team has always been willing to be unpopular and caution people that a sustainable biofuels industry has to take into account a wide range of production, economic, and environmental factors,” Whitson says. “We take our role as stewards of the land very seriously.”

Use of cellulosic biomass – plant material from grasses and forage, forest waste products, and similar sources – seems to be a vital component to avoiding the negative economic and environmental effects related to corn-based ethanol production experienced during the past few years.

“Many people want a fully functional biobased energy industry right now,” Huhnke says. “Unfortunately, it’s still a few years down the road, even though we have been studying how to make a sustainable biofuels industry viable for a while now.”

In short, science moves at the speed science moves. The potential payoff is obvious, though, not only at the pump for consumers but in the revitalization and prosperity of rural communities.

Phil Kenkel, Fitzwater Chair in the OSU Department of Agricultural Economics, estimates that a 50-million-gallon biorefinery would generate a one-time boost to the local economy of $90 million during construction and boost economic activity by more than $60 million on an annual basis.

“A typical biorefinery will create 30 to 35 fulltime jobs while the plant’s spill-over effects can result in 80 to 90 additional jobs in supporting industries,” Kenkel says. “The business structure of a biorefinery has a major impact on the local economy.”

Studies indicate that ethanol projects organized as farmer cooperatives or through investment from a local community have approximately twice the positive economic effect relative to projects funded by out-of-state-investors.

Partners promoting progress and prosperity

Under the auspices of the Oklahoma Bioenergy Center, scientists at OSU are working in unison with researchers at OU and the Samuel Roberts Noble Foundation to enhance the state’s ability to be a significant contributor to and take greater advantage of the national ethanol effort.

“Oklahoma is ideally suited to be a leader in biofuels and bioenergy research, as Gov. Henry stated when he announced the Center initiative in January 2007,” Whitson says. “Oklahoma produces many of the most promising energy crops and has a noteworthy tradition as both an energy and agriculture state.”

Biofuels research supported by the Center includes development of feedstocks, collection and transportation, conversion technologies, and distribution. The Center also features an education component to help interested farmers and ranchers make the transition to energy crops and adopt best management practices.

Gov. Henry and the State Legislature initiated funding at $40 million over a four-year period.

The creation of the Center came on the heels of the federal government mandating the annual production of 35 billion gallons of biofuels by 2017. The United States only produced about 5 billion gallons of biofuels in 2006.

“Our biofuels research has always been a multi-college effort and now we’re increasingly becoming multi-institutional,” Whitson says. “We in the Division have long believed and promoted that an interdisciplinary outlook is the best way to develop solutions to the challenges facing society, and solving real-world issues is a vital part of the land-grant mission and the reason why OSU exists. It’s who we are at our core.”

For a PDF version of this story, please visit:  http://www.vpr.okstate.edu/publications/Vanguard%2008.pdf#page=1 

Donald Stotts