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SUMMER 2006
Turning Timber Into Black Gold
by Susan Varlamoff

Transforming “biomass,” the products and byproducts of farm or forest, could provide a renewable, local, and profitable alternative to oil. And Georgia, a veritable Saudi Arabia of biomass, is well placed to lead.

Though oil is a nonrenewable energy source whose supplies are decreasing, the United States is still hooked on it. Petroleum provides 40 percent of America’s total energy needs and most of it — 70 percent — is used for transportation. As U.S oil supplies dwindle, more than 60 percent is imported.

To ease America’s heavy reliance on petroleum, University of Georgia engineers have been experimenting with the renewable alternative of biofuels, and plans are underway to convert the campus transit system which includes the nation’s largest university bus fleet accordingly.

For more than 20 years, biofuel’s research and pilot projects have been conducted on the campus and around the state. In the 1980s, for example, UGA buses were fueled with diesel made from peanut oil. During the winter of 2002, the buildings were heated using animal fats, plant oils and grease. Electricity was generated in north Georgia in 2004 by burning chicken litter.

With near-record prices for gasoline and rising concerns about global warming, converting to biofuels makes good environmental and economic sense for the country and for the state. “Biofuels made from Georgia agricultural and forestry products could be a major factor in Georgia’s future rural economic development,” said Tom Adams, director of UGA’s Engineering Outreach Service and a member of the faculty of engineering.

Using biofuels for energy is not avant-garde. In the 19th century, fish and whale oils were used for heat and light. Henry Ford, who descended from farmers, envisioned ethanol (a type of alcohol, made from biomass) to fuel his first cars. About 100 years ago, Rudolf Diesel used peanut oil to demonstrate the engine that bears his name.

Drawing inspiration from their predecessors, UGA engineering faculty and an interdisciplinary group of colleagues are developing a pilot-scale biorefinery on campus that can process different types of biomass — agricultural and forest waste, for example — into multiple products such as ethanol, hydrogen, bio-oils and char (a product similar to charcoal). A UGA-led consortium of universities, federal labs, and companies is operating the facility.

Biorefinery technologies not only provide alternatives to fossil fuels but also emit smaller amounts of atmosphere-warming carbon dioxide, said K.C. Das, a professor of engineering and coordinator of UGA’s Biorefining and Carbon Cycling Program. “The biorefinery actually sequesters carbon,” Das said, keeping it out of the air altogether.

The researchers began with a simple idea: despite the chemical differences between hydrocarbons (such as coal and oil) and carbohydrates (complex sugars found in plants), both types of materials contain carbon, the essential ingredient for fuels. “We realized,” said Das, “that all we’re missing is a process that can mimic nature’s ancient conversion of biomass to fossil fuel.”

In that spirit, they have been adopting an old coke-manufacturing technique, called pyrolysis, to transform biomass into renewable biofuels [see sidebar on page 27]. “You basically take peanut hulls, say, and heat them to 450-500 degrees Celsius,” Das said. “In the absence of oxygen, the cellulose decomposes and forms oil. It looks a lot like engine oil, but it’s a little more viscous.” Meanwhile, the product is carbon-neutral: it doesn’t add any more carbon to the atmosphere than what the biomass from which it came took up during plant growth.

Other bio-oils created in the high-temperature process can be collected for a variety of non-fuel products such as flavorings and adhesives. In addition, UGA researchers are engineering porous char, another byproduct of pyrolysis, which can be used to remove sulfur, nitrogen and carbon dioxide — all contributors to global warming — from industry smokestacks.

This technology not only provides markets for agricultural products and byproducts but also has the potential to rejuvenate a depressed forest industry in rural Georgia; two-thirds of the state is covered in forest. Georgia also leads the nation in poultry production, which results in huge quantities of chicken litter. UGA engineers are studying how a biorefinery could transform such revenue-streams-in-waiting into fuel for transportation, electricity and even natural gas.

It turns out that the greatest concentrations of biomass in the state occur in counties where local economies have been suffering the most. Retrofitting pulp and wood-product mills into forest biorefineries would provide new uses for the biomass while creating new jobs.

“Biorefineries, out of necessity, need to be distributed across the state, as the economic hauling distance for biomass is only about 40 miles,” said Adams, who initiated the University’s biorefinery research. “Geographically distributed production also has the advantage of providing fuel-supply security because that production is not concentrated in a few locations, as is the case with oil refineries.”

In 2006, UGA’s biorefinery will begin producing ethanol from waste flour, along with biodiesel from cotton seeds or animal fats, to power campus vehicles. In the future, Adams envisions sweet potatoes or other crops being used to make ethanol for Georgia’s cars and trucks. E-10 (a mix of 10 percent ethanol and 90 percent gasoline) will be used for the UGA fleet of conventional cars. The university’s buses and diesel trucks will be fueled with B-20 (20 percent biodiesel and 80 percent diesel). And as its fleets of cars and trucks wear out, they will be replaced by flexible-fuel vehicles that can run on E-85 (85 percent ethanol and 15 percent gasoline). This plan also has great practicality: flexible-fuel vehicles require minimal changes at the manufacturing level and cost about the same as those powered by gasoline.

“It’s a no-brainer to use biofuels for UGA’s cars and trucks,” said Bill Fox, an agricultural economist and UGA fleet manager. “UGA will save approximately $100,000 in fuel costs by using E-10 and B-20.”

At a recent biofuels symposium sponsored by UGA’s Engineering Outreach Service, Helena Chum, a scientist with the National Renewable Energy Laboratory, maintained that biomass fuels are the wave of the future. “In the same way that petroleum refineries transformed the 20th century, biofuels will transform the 21st century,” she said, noting that Georgia has the potential to be a leader in the transition from a petro-economy to a bio-economy.

“We have seen how the promise of biofuels has benefited the environment and the economy of Brazil,” said Adams. “There is no reason why we can’t do the same in Georgia.” Already, he added, “Industries are coming to our campus looking for local alternatives to gasoline, diesel and natural gas to reduce their energy costs and stay competitive.”

For more information contact Tom Adams at tadams@engr.uga.edu or K.C. Das at kdas@engr.uga.edu.