On a cool April morning, more than 250 runners gather along Cherokee Boulevard in Knoxville, stretching calves and hamstrings, taking in fluids, and stoking their internal engines with bananas and orange slices.
While the runners fuel up, a fleet of vehicles that includes everything from SUVs to full-sized Knoxville Area Transit buses occupies a capacious parking lot beside the Tennessee River. All are powered entirely or in part by alternative fuels (alt-fuels)—biodiesel, ethanol, electricity, propane, and compressed natural gas (CNG)—and together serve as thematic props for the fourth annual “Run for Clean Air.”
Jonathan Overly, the event organizer, can claim partial responsibility for the incremental—but nonetheless vital—improvements in the air the runners will draw into their lungs as they complete the 5K course.
Overly serves as the executive director of the East Tennessee Clean Fuels Coalition (ETCFC), a regional participant in the Department of Energy’s (DOE) Clean Cities Program, an outgrowth of the Energy Policy Act of 1992. Since 1993, 83 organizations have earned the DOE Clean Cities designation, and collectively they promote alt-fuel production and use across the nation.
Overly, who was named coordinator of the year at the 2006 National Clean Cities Convention, also serves as a senior research associate with the University of Tennessee’s Institute for a Secure and Sustainable Environment.
East Tennessee is home to some of the nation’s most visited recreation areas, including Great Smoky Mountains National Park. The region also claims a far less laudable distinction—in the American Lung Association’s “State of the Air: 2006,” the Knoxville–Sevierville–LaFollette triangle ranked as the nation’s 14th most ozone-polluted area. In the 2005 report, Knox County had the worst particle pollution in the state.
All of the fuels Overly promotes present cleaner emission profiles than conventional petroleum, but he regards the biofuels—biodiesel and ethanol—as the current standouts of the alt-fuels suite. (For more information on these fuels, see the sidebar “Fueling the Future.”)
“Biodiesel is called the ‘clean burn’ because it reduces emissions for almost all airborne pollutants,” says Overly, who himself drives a truck powered by the alt-fuel. “A blend of B20 [20 percent biodiesel and 80 percent petroleum-based diesel] reduces carbon dioxide emissions by 15 percent, sulfur dioxide by more than 19 percent, and particulate matter by 12 percent.”
Ethanol produced from corn, currently the main feedstock for the fuel in the United States, also achieves improvements over petroleum- based fuels in all tailpipe emissions, though the benefits are not as dramatic when lifecycle impacts are factored in.

Curbing air pollution is but one of ETCFC’s missions. The other key goals are reduced U.S. dependence on petroleum and the economic growth and development spurred by producing and using alt-fuels.
Currently about 70 percent of the oil used in the U.S. goes for transportation. And more than 60?percent of the petroleum fueling the quarter-billion vehicles operating on the nation’s highways—over 10 million barrels a day—comes from outside the United States, according to the federal Energy Information Administration.
“We spend over $300 million per day—more than $2 billion per week—for foreign oil,” says Overly. “ETCFC and the Clean Cities Program are helping to devise ways to direct that money back into the U.S. economy.”
Furthermore, Overly says, gasoline prices fail to reflect the real cost of petroleum, which should include the cost of environmental cleanup, the billions of dollars spent annually to protect oil corridors in the Middle East, and the cost of transporting petroleum thousands of miles from foreign lands.
Overly hastens to point out that 100 percent of the biodiesel and ethanol, 95 percent of the electricity and propane, and 90 percent of the natural gas we use are produced domestically. Biodiesel and ethanol, which are renewable, promise significant economic rewards to the nation’s alt-fuel producers, including farmers who grow the feedstocks.
The governor of Tennessee, Phil Bredesen, has pledged $72.6 million in research funds and created an alt-fuels working group to “increase Tennessee’s use of renewable alternative fuels.” (See the sidebar “Homegrown Energy.”)
“Tennessee’s production capacity in ethanol and biodiesel will dramatically increase over the next two years,” says Paul Sloan, deputy commissioner of the Tennessee Department of Environment and Conservation. “Market prices?and education will be the big factors in establishing the demand side of the equation.”

The realm of education and outreach to increase demand is where Overly’s organization really shines.
When Overly established ETCFC in 2002, not a single public or private fleet in East Tennessee was powered by either biodiesel or ethanol. Four or five were using other alt-fuels but only on a relatively small scale. What’s more, few individuals or fleet managers had more than a passing knowledge of alternative fuels or a notion of where to find them.
Today 10 suppliers in East Tennessee provide biodiesel blends, and more than 100 public and private fleets use blends ranging from B20 to B100 (pure biodiesel). Among the alt-fueled fleets in Knox County are Knoxville Area Transit, the City of Knoxville, the University of Tennessee, and the Knoxville Utilities Board (KUB).
According to Overly, all 900 of KUB’s vehicles run on alt-fuels.
Many of the region’s consumers are burning E10 (10 percent ethanol and 90 percent gasoline) without even realizing it, says Overly. Pilot Travel Centers throughout Knox County proffer the alt-fuel blend at all their gasoline pumps.
“Without the efforts of ETCFC, Tennessee would not have been in the position to do what it is doing now with alt-fuels,” says Sloan. “Jonathan has gained the confidence and respect of businesses and governmental users.”
ETCFC draws $60,000—half of its current operating budget—from the state and receives membership dues and sponsorship from its partners, which include Oak Ridge National Laboratory, Eastman Chemical, and Pilot Travel Centers. Nu-Energie LLC, a biodiesel production company based in Hawkins County, recently became an ETCFC partner and awarded the coalition $10,000.
The annual Run for Clean Air is one of ETCFC’s many public events intended to raise awareness and acceptance of alt-fuels among private consumers, as well as with public and private fleet operators.
Call the run a soft sell. But Overly’s crusade to boost alt-fuel’s use can assume a more direct approach. In March Overly staged a half-day biodiesel workshop—one of a dozen such events he’s organized since 2004—in Morristown, Tennessee. Through that event Overly made the case for alt-fuels and presented a number of public and private fleet operators who had made the switch to biodiesel and were happy to give their testimonials and offer advice to prospective users.
Similar efforts have contributed to widespread adoption of alt-fuels, chiefly biodiesel, by municipal and county—as well as private—fleets in most of East Tennessee’s 32 counties.
Last year, Overly reports, alt-fuel use in East Tennessee displaced 7.5 million gallons of petroleum-based fuels. Nationally, domestic biodiesel use increased from a half-million gallons in 1999 to 75?million gallons in 2005, according to the National Biodiesel Board (NBB), and was expected to triple that number in 2006. NBB reports that the 105 U.S. biodiesel manufacturing plants boast an annual production capacity of 864 million gallons.
“Biodiesel is an easy-to-use fuel in that B20 formulations don’t require any modifications to diesel vehicles or their engines,” says Overly. “In fact, Rudolf Diesel’s first engine ran on peanut oil.”
Though Overly assumes many roles for ETCFC, he regards himself first and foremost as a salesman, and he’s learned that drawing people into the alt-fuels tent can require different messages.
“Some people don’t care all that much about air quality, but I can hook them on buying fuels produced right here at home,” says Overly. “Others couldn’t care less about where their fuels come from, but they care deeply about improved air quality.”
In the end, motivations don’t matter all that much.
“When it comes to adoption of alt-fuels,” he says, “regardless of what prompts it, it’s all good—good for the region, good for the nation, and good for the environment.”
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For more information, contact Jonathan Overly, 865-974-3625, or e-mail jgoverly@utk.edu. Visit the ETCFC website at www.ETCleanFuels.org.
Though all alternative fuels (alt-fuels) offer some advantages over traditional petroleum products, biodiesel and ethanol remain the two leading contenders for widespread domestic production and use.
Biodiesel—a renewable, biodegradable, nontoxic, and carbon-neutral fuel—is produced from vegetable oils (chiefly soybean) or animal fat through a process called “transesterification.” In this process, the triglyceride (the fat or oil) reacts with alcohol (typically methanol or ethanol) in the presence of an alkaline catalyst (sodium or potassium hydroxide). The end product is methyl ester—the chemical name for biodiesel—and glycerin.
Biodiesel is typically offered in blends ranging from B5 (5 percent biodiesel and 95 percent petroleum-based diesel) to B100 (entirely biodiesel).
In the United States, ethanol is a fuel largely produced through fermentation of cornstarch (consider it a 200-proof moonshine elixir for your car). The fuel is still shaking off a bum rap it received in the 1980s, when critics claimed—with justification—that it required more Btu’s to produce ethanol than the resulting ethanol would yield. Much has changed since then.
For one thing, according to “Energy and Greenhouse Gas Emissions Impacts of Fuel Ethanol,” a report released by Argonne National Laboratory (ANL) in 2005, U.S. corn output per pound of fertilizer has risen by 70 percent in the past 35 years. Meanwhile the energy efficiency of ethanol production facilities has also improved, by as much as 60 percent, over the same period, and crop yields for corn have improved substantially, as well.
Furthermore, in a twist of a well-worn adage, you can burn your corn and feed it too: in ethanol production, a third of the initial corn-kernel mass ends up as animal feed.
On its own, ethanol produced from corn achieves a modest improvement over petroleum-based fuels in greenhouse-gas emissions, but it also acts as an oxygenate—an oxygen-containing additive that can boost gasoline’s octane quality, enhance combustion, and reduce exhaust emissions—in ethanol-gasoline mixtures.
But cellulosic ethanol, produced from fibrous plants like switchgrass and poplar trees, promises to reduce greenhouse-gas reductions by as much as 64 percent of the emissions produced by conventional fuels, according to a 2005 report produced by ANL. Increased reliance on cellulosic ethanol will also divert less corn from the nation’s food supply.
Breaking down cellulosic biomass, which includes the entire plant, into simple sugars is more challenging—and thus, more expensive—than producing ethanol from grains. But cellulosic biomass is more abundant and cheaper to grow than corn, which helps offset the increased cost of production.
Though Henry Ford designed his 1908 Model T to run entirely on alcohol, modern automobiles must be equipped with “flexible-fuel” engines to burn formulations of more than 10 percent ethanol. These specially designed engines can burn any gasoline–ethanol formulation that includes up to 85 percent ethanol.
— D. B.
Each year, the U.S. federal government spends billions of dollars on research and development on project areas as wide-ranging as defense, energy, the environment, agriculture, and human health.
Among programs receiving federal energy research funds is the Automotive Lightweighting Materials (ALM) Program. ALM, part of the Department of Energy’s Office of FreedomCAR and Vehicle Technologies, seeks to develop and validate technologies that produce advanced lightweight materials for use in vehicles.
These materials—including carbon-fiber polymer composites, aluminum, magnesium, and advanced high-strength steel—can significantly reduce the weight of vehicles. ALM’s goal is to achieve weight reduction without compromising safety, performance, recyclability, or affordability. Less weight can mean improved fuel efficiency, which reduces harmful tailpipe emissions per driver mile and curbs dependence on foreign sources of oil.
But how much of the money invested in these programs has actually produced results? That’s a critical question, according to Jean Peretz, a research leader with the Institute for a Secure and Sustainable Environment (ISSE) at the University of Tennessee (UT).
“With limited funds available for R & D, Congress and federal agencies are placing increased emphasis on determining whether federal spending on research is benefiting the general public,” Peretz says. “ALM’s goal is particularly challenging in that the federal government does not manufacture cars. Instead, ALM works collaboratively with the big-three automakers, national laboratories, and automotive suppliers, who ultimately will choose to implement ALM’s research findings.”
But assessing benefits can be a complex task because payoffs come in many forms. For one thing, short-term benefits may be more intellectual than monetary. For instance, a project may increase knowledge and understanding even if a particular technology fails to work.
For another, unexpected benefits may result. Knowledge gained on one project, for instance, might improve the efficiency of future federal R & D projects. Beyond that, an R & D project may result in improvements in a process rather than creation of a new technology, or it might facilitate new collaboration among researchers whose combined expertise produces benefits not likely to derive from their individual efforts. And finally, benefits may not be realized for several years.?
Peretz, along with ISSE program leader and UT political science professor Bruce Tonn and Oak Ridge National Laboratory researcher Sujit Das, recently evaluated nine selected ALM projects. The effort produced the report “Automotive Lightweighting Materials Benefit Evaluation,” released in November 2006, which builds on two earlier reports (2001 and 2002) that developed and tested the evaluation framework. The evaluations assess short-run outputs and long-term outcomes that may be attributable to ALM projects.
For more information, contact Jean Peretz at 865-974-3803 or e-mail speretz@utk.edu. Access the report at isse.utk.edu