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FALL 2007
Fueling the Future of Bioenergy
by Charles Seabrook

You won’t find any derricks or oil-well pumps in Georgia like those that dot the landscapes of Texas and Oklahoma. Georgia has no known commercially viable deposits of bubbling crude.

What Georgia does have is abundant farmland and forestland teeming with huge amounts of biomass—raw material for making ethanol and biodiesel, the so-called biofuels. The state has 24 million acres of commercial forests, an expanse second only to Oregon’s. Georgia’s farms are capable of producing millions of tons of other biomass—including switchgrass, peanuts, sweet sorghum, soybeans, corn, wheat, and canola. And the potential doesn’t end there. Grasses, cornstalks, sawdust, hog manure, paper pulp, and logging debris are all possible raw materials, or feedstocks, for biofuels. Georgia’s poultry-processing plants alone annually produce millions of gallons of chicken fat that could be rendered into biodiesel.

Given these vast “reserves,” the University of Georgia’s Ryan Adolphson and other bioenergy experts envision the state as a leading biofuels producer—in effect, “the Saudi Arabia of biomass.” But until biofuels become cost-competitive with gasoline, UGA researchers say, they will continue to represent only a small and subsidized niche of the transportation-fuel market.

To fully tap biomass as a major fuel source will require a slew of scientific and technological advances that range from a basic understanding of plant growth, to the genetic engineering of biomass that will make it more amenable to efficient refining methods. The DOE is pushing hard to speed up such research—a mission, some say, that may ultimately rival the manned moon-landing program of the 1960s both in scale and ambition.

From Basic Science to Useful Products

Poised to play a pivotal role in this new “moonshot” is the University of Georgia, which will be a lead player in one of the nation’s most extensive bioenergy-research projects to date—an endeavor to unravel the tightly held secrets of cellulosic biomass, a basic component of green plants and a key factor in the mass production of biofuels. A primary goal is to make so-called cellulosic ethanol cost-competitive with gasoline by 2012, which should help reduce America’s gasoline consumption by 20 percent in the 10 years thereafter.

Alan Darvill, cofounder and director of the Complex Carbohydrate Research Center (CCRC), is heading the grant team, which will work in collaboration with researchers at several other select institutions. Together, they will comprise a new research center—the Bioenergy Science Center (BESC)—headquartered at Oak Ridge National Laboratory in Tennessee. Other members include Georgia Tech, the University of Tennessee, Dartmouth College, the Samuel Roberts Noble Foundation, and the National Renewable Energy Laboratory. The center also includes companies—ArborGen in Summerville, S.C.; Diversa in San Diego, Calif.; and Mascoma in Cambridge, Mass.—as well as several independent researchers from around the country.

“This research uses biotechnology to reduce the high cost of processing trees and other plants into biofuels,” says Darvill, “and has the potential to make ethanol a significant replacement for fossil fuels for this country’s future energy needs.”

The DOE announced in June that it would invest up to $375 million over the next five years in BESC and two similar research consortiums—one based in Madison, Wis., and the other near Berkeley, Calif.—on basic science that may aid the development of cellulosic ethanol and other biofuels. Worth noting is that these three consortia were the survivors of an intense competition—and that CCRC’s strengths in plant cell-wall structure analysis, plant genetics, and microbial biochemistry were major factors in BESC’s win. The center is slated to receive $125 million, of which UGA’s portion will be about $20 million.

Advances in such fundamental science are critical to the applications—biofuels as a major energy resource—down the road. UGA can thus be a major player on both counts: its strength in basic research and its engineering expertise in applying the science to derive useful products.

Much of UGA’s past applied work has centered on its “integrated biorefinery,” built on campus in 2004. This facility “is unique,” says E. Dale Threadgill, head of UGA’s faculty of engineering, because it can process a variety of biomass types—from wood chips to chicken manure—to generate both liquid fuels and bioproducts. Moreover, says Adolphson, who directs UGA’s biomass-processing facilities, “We’re looking at the broad spectrum of biomass-to-energy—similar to how a petroleum refinery takes a barrel of crude and makes not just gasoline and diesel but also many other useful products.”

Toward Easing the Pain

Biofuels themselves are nothing new. Henry Ford initially planned to use ethanol (the alcohol in alcoholic beverages) as the primary fuel for his Model T. German engineer Rudolf Diesel designed the first engine bearing his name to run on peanut oil or vegetable oil, as he demonstrated at the World Exhibition in Paris in 1900.

But even in the early going, biofuels took a back seat to oil. Ford opted for gasoline as the dominant fuel for his cars because it was cheaper, and in the ensuing decades biofuels stayed in the backseat. Then came the Arab oil embargoes of 1973 and 1979, when gasoline prices in the United States shot up and long lines appeared at gas stations because of shortages. These “crises,” as they came to be known, made the nation realize how vulnerable it was to the whims of foreign oil producers.

As a result, biofuels gained renewed interest among researchers, including an enthusiastic group at UGA. In a pilot project, several campus buses were modified to run on diesel blended with up to 80 percent peanut oil. During February 2002, the university heated the entire campus for six weeks using animal fats, oil, and grease—substitutes for No. 2 fuel oil. Based on UGA research, electricity was generated in north Georgia in 2004 by burning chicken litter.

Most of these biofuels demonstrations received only nominal public attention, however, as petroleum fuels were again plentiful.
But now, several phenomena have converged to push biofuels to center stage—and probably keep them there. Global oil demand is growing fast, while supplies are tightening. Tension is brewing in several oil-rich regions, jeopardizing their reliability as future oil sources for the United States. The worldwide price of oil has soared to as much as $77 a barrel.

Consumers are feeling the pinch at the pump, where gasoline prices have hovered around $3 per gallon, and predictions are that the situation will worsen instead of improve.
In addition, global warming, which a majority of scientists say is caused mostly by fossil-fuel burning, has become a major threat around the world.

Biofuels can help ease much of this pain, scientists say. For one thing, burning biofuels instead of petroleum can produce fewer emissions of carbon monoxide, particulates, and other contaminants, thereby relieving areas plagued with air pollution. And biofuels could also slash emissions of carbon dioxide—the main gas behind global warming. K.C. Das, director of UGA’s biorefining and carbon cycling program and his colleagues are working on methods that would allow the widespread use and production of biofuels while “sequestering carbon” in the soil to keep excess amounts of it out of the air.

Breathing New Life into Rural Economies

Last February, the promise of biomass-to-energy prompted an elite group of scientists, agriculture officials, business leaders, and others—dubbed the 25x’25 National Steering Committee—to predict that “America’s farms, ranches, and forests will provide 25 percent of the total energy consumed in the United States” by 2025. The committee’s report outlined numerous benefits for the nation including:

• Generating $700 billion in new economic activity annually
• Creating 4 million to 5 million new jobs
• Reducing overall oil consumption by 2.5 million barrels per day—10 percent of total projected U.S. oil use in 2025
• Reducing carbon-dioxide emissions by 1 million tons—two-thirds of projected emissions growth by 2025.

“These are noble and achievable goals,” says UGA’s Threadgill, a National Steering Committee member. “And we can do it while continuing to produce safe, abundant, and affordable food, feed, and fiber.”

Georgia and the rest of the South, with vast farmlands and forestlands, are expected to reap huge benefits from all of this. “It will breathe new life into rural economies, many of which are dying on the vine,” says Tom Adams, who oversees UGA’s engineering outreach efforts.

To a certain extent, biofuels are already helping revive rural economies in Georgia. At least 10 biodiesel plants and eight ethanol production facilities are in production, under construction, or planned for the state

One of the new biodiesel plants is located in Gordon, a town in Middle Georgia’s rural Wilkinson County. Built by Macon-based Alterra Bioenergy, the plant will initially produce 15 million gallons of biodiesel per year, eventually doubling that output. The feedstock will be soybean oil, most of it coming from Georgia farmers. Alterra president Wayne Johnson notes that he relied heavily on the expertise of UGA engineers to help design the plant and provide technological know-how. “We probably wouldn’t be here if it weren’t for UGA,” says Johnson, whose company is also building another biodiesel plant in Plains and hopes to open other facilities around the state.

In Gordon, Mayor Ken Turner is ecstatic about Alterra’s plant—and the jobs it will bring to this economically depressed area. He is also proud of the town’s efforts on its own behalf. “We went out and courted them to come here,” says Turner.

Corn is Not the Answer

Alterra will make biodiesel through a well-known process called “transesterification,” in which vegetable oils are mixed with methanol and a catalyst and then heated. But a big challenge facing biodiesel producers is feedstock. Most oils that are potential biodiesel raw material are also used in food and have associated high prices. And while there other potential feedstocks—chicken fat, for instance—that are currently plentiful and inexpensive, higher demand could drive their prices up too. Some feedstocks might also need more processing to be rendered into biodiesel. Chicken fat in particular has a high fatty acid content, which makes extra preparation necessary.

UGA researchers are working to find solutions to these problems, such as developing copious oil-producing crops. An example is canola, which would grow abundantly as a rotation crop in Georgia’s mild winters.

For ethanol, the picture is more muddled. In his State of the Union address last January, President Bush called for the annual production of 35 billion gallons of alternative fuel—mostly ethanol—by 2017. The Senate, in the energy bill passed in June, set a 36 billion-gallon target by 2022. These are staggering goals, given that the nation would have to increase its present ethanol output sevenfold.

Nationwide, more than 121 ethanol biorefineries are operating, and another 75 are under construction, according to the Renewable Fuels Association. All of these plants on line, it estimates, would produce 12.6 billion gallons of ethanol a year, far short of the above goals. Moreover, nearly all of the ethanol plants are designed to use corn as the feedstock—the Southeast’s biggest corn-to-energy plant is under construction in Camilla, Ga.—and the cost of making ethanol this way may be more than the nation can bear. One reason is that only about 20 percent of each gallon is “new” energy. A lot of petroleum diesel is currently needed to operate tractors, harvesters, and irrigation equipment; and natural gas is used to make fertilizer and run the biorefineries. In addition, growing and processing corn requires a lot of water, the use of which is becoming a bone of contention in many states faced with water shortages.

Finally, as more corn is used to make ethanol, less of it is available for the production of food and livestock feed, thus driving up their prices. In May, Iowa State University researchers estimated that U.S. consumers will pay $47 more per person per year for food as a result of higher corn prices—a nationwide increase of about $14 billion.
These issues lead UGA’s Threadgill to declare: “The future growth in biofuels won’t be in corn ethanol.”

Probing the Secrets of Cellulose

So how will the nation produce the copious amounts of ethanol needed to meet its goals of the next decade? The consensus answer is cellulosic ethanol—from trees, wood debris, switchgrass, and other abundant sources of cellulose, which is the most plentiful biological material on Earth. In essence, cellulosic ethanol is more energy-efficient than corn ethanol and uses more abundant and diverse feedstocks that, unlike corn, are not used for food production.

Cellulose is the main constituent of all plant tissues and fibers. The wood in a tree may be 50 percent cellulose or more. In cotton in its raw state, that figure is about 91 percent. But while cellulose contains tremendous amounts of sugars that can be fermented into ethanol, doing so is currently much more complicated and costly than making it from corn, according to John McKissick, coordinator of UGA’s Center for Agribusiness and Economic Development.

The main problem is that the simple sugars in cellulose are locked up in complex chains of molecules that nature remarkably created “to resist biological and chemical degradation,” says Joy Peterson, a UGA microbiologist.

Much of Peterson’s research focuses on finding novel and low-cost enzymes that can efficiently break down cellulose, overcoming “cell-wall recalcitrance” and releasing large amounts of sugars and starch. The enzymes now used in this so-called “enzymatic process” are very costly, a major barrier to producing ethanol on a commercial basis.

Thus the DOE wants to speed up the search for inexpensive enzymes and other cost-effective ways of breaking down plant-cell walls. That is the prime motivation behind its $375-million, five-year commitment to the three new centers. Participating researchers, from UGA and other select institutions, will focus mostly on the cellulose of fast-growing poplar trees and switchgrass, which is native to the United States and can be grown with minimal effort throughout most of the country, including Georgia. One aim of the research is to develop a group of microorganisms that could break down plant matter, through an efficient one-step conversion process, into biofuels.

Investigating Alternative Processes

Meanwhile, other UGA researchers will continue their investigations into the major alternative to the enzymatic process, called the thermochemical process. In this approach, solid biomass is converted to a gaseous or liquid fuel by heating it in a limited-oxygen environment prior to combustion. Last May, Tom Adams of UGA’s faculty of engineering announced that he and his colleagues were using a thermochemical technique to produce a new biofuel from wood chips. “Compared to Fischer-Tropsch technology, it’s very easy to do,” said Adams, “and we expect to reduce the price of producing biofuels from biomass dramatically with this technique.” He added, however, that it would probably take a few years to perfect.

In Soperton, Ga., ground has already been broken for a sprawling new plant that will use another, still-proprietary thermochemical method to produce as much as 100 million gallons of ethanol a year from pine chips. If all goes as planned, the plant, being built by the firm Range Fuels, could be the first to demonstrate that ethanol can be produced from cellulose on a commercial scale. Success would give thermochemical-process proponents chest-thumping rights over supporters of the enzymatic process.

Proponents of the alternate approach, though, are laying their own plans. C2 Biofuels, a company working with Georgia Tech and UGA’s Peterson, is planning to build a cellulose-to-ethanol plant in Georgia using the enzymatic process.

There is much skepticism, however, over whether either plant will prove commercially successful, given the many unknowns about cellulosic ethanol. But Adolphson says that having such plants up and running will allow researchers to determine where adjustments or redesign might put the processes on track to becoming efficient and competitive ethanol producers.

Researchers and Funders Confident

Government is helping the prototype plants get off the ground. In February, the DOE said that Range Fuels in Soperton and five other cellulosic ethanol plants in the nation would be eligible for $385 million in construction and production grants. Range Fuels itself is in line for $76 million. Georgia has also embraced Range Fuels, offering it tax abatements, low-cost land, and grants that could total more than $10 million. In addition, U.S. Senator Saxby Chambliss of Georgia, ranking member of the Senate Agricultural Committee, has introduced a measure to boost fuel derived from pine trees and other cellulose sources.

Critics often deplore the subsidies and other special favors, but supporters, such as UGA’s McKissick, say they are very helpful and even necessary to launching a promising new technology that could be of great benefit to the nation.

Bioenergy experts say it is too early to predict which process—thermochemical or enzymatic—will emerge as the dominant technique for making cellulosic ethanol. Possibly both will enjoy considerable use when the current obstacles are overcome.
In the meantime, there are other technological and economic challenges—among them developing efficient ways of growing and harvesting biomass crops, delivering the feedstocks to biorefineries, and getting the biofuels economically into consumer fuel tanks at the filling station.
Environmental questions remain as well. For example, will massive production of cellulosic ethanol decimate our forests? Will our rivers and streams suffer from erosion caused by putting more land into biomass crops? Researchers at UGA and elsewhere are confident that the hurdles will be overcome. “We’re not there yet,” says Adolphson, “but we can see it from here.”

(Charles Seabrook recently retired from the Atlanta Journal-Constitution, where he was a science and environmental writer for 33 years).