Students Take Veggie-Fueled "BioBus" on Eco Road Trip

Jennifer Vernon
for National Geographic News
October 19, 2004
No practical fuel alternative to gasoline? Tell that to the Project BioBus team from Middlebury Collegy in Vermont. Their planned 15,000- mile (24,140-kilometer) tour around the United States this fall is intended to stop even the most hardened skeptics in their tracks.

The trip is designed to demonstrate the feasibility of using vegetable oil-derived "biodiesel" fuel at schools—for bus fleets, maintenance equipment, and even furnaces. To prove that point, the group is undertaking the journey in a school bus powered solely by biodiesel.

Biodiesel, according to the Project BioBus Web site, "is a safe, renewable, clean burning, domestically-produced fuel made from vegetable oils (such as soy and rapeseed) that can be used in existing diesel engines without modifications." This eco-friendly fuel is refined from vegetable oil, including fryer oil from fast-food restaurants, by combining it with lye and methanol.

Beyond trying to convince schools to consider the switch, the Project BioBus team hopes to show the public at large the benefits they see in biodiesel: no necessary lifestyle changes, drastically reduced harmful emissions, less dependence on foreign oil, and support for U.S. farmers and related industries.

The 13-member team of Middlebury College students and alumni began their trek September 13 in Vermont with a U.S. $10,000 grant from the college. They are making a wide loop around the U.S. to visit over 20 major cities by the beginning of December.

Ready for Veggie?

With recent oil prices topping $50 a barrel, the public is becoming more interested in alternative fuel sources, says team member Stephen Swank.

"People know that it's a big problem," Swank said. "We realized that we have a responsibility to influence fellow students and … generations below us on the subject."

With that mission in mind, the team uses the bus, brightly painted with scenes of corn fields, as a focal point for their presentations to elementary, middle, and high schools, as well as to colleges, universities, and "green"-minded institutions.

The 2004 BioBus is actually the second such vehicle these students have built and road tested. A 1991-model school bus with 140,000 miles (225,000 kilometers) to its credit, this latest bus gets an average of 8 miles per gallon (or 3.4 kilometers per liter) of biodiesel, which is on par with petroleum diesel buses, Swank said.

After adding a 100-gallon (379-liter) tank to the existing 60-gallon (227-liter) one, the 2004 BioBus has an impressive 1,300-mile (2,092-kilometer) range per fill-up.

The idea for this year's journey sprang from the success of the original BioBus, which was developed around a rock climbing trip the students planned for the summer of 2003. Learning that some Volkswagen Jetta diesel car models are equipped to run on vegetable oil, they purchased a 1989 GMC bus with 200,000 miles (321,869 kilometers) on the odometer and modified it to do the same.

The group stopped at fast-food restaurants to collect used vegetable oil for fuel and traveled 6,000 miles (9,600 kilometers) with no mechanical problems, garnering major media attention along the way.

Biodiesel vs. Vegetable Oil

This year's bus differs from the first in that it runs on biodiesel provided by local sponsor distributors instead of waste vegetable oil.

Though closely related, biodiesel has an advantage over vegetable oil: No engine modifications are needed to keep the fuel warm, says Sabrina Trupia. Trupia is a chemist with Vermont's nonprofit Biorenewables Education Center and fiscal advisor to Project BioBus.

"As a fuel, biodiesel is equivalent to petroleum diesel," Trupia said. While other alternative fuel sources like natural gas are being used today, biodiesel has the added advantage of being renewable. "Biodiesel is just as clean, and you can always make more of it," Trupia said.

So how is biodiesel made? The process is so simple that the BioBus team regularly demonstrates it to the classrooms they visit. "We can do it in these labs at schools just in front of the kids and they love it," said team member Swank, a Middelbury senior majoring in molecular biology and biochemistry.

Vegetable oil contains glycerin, a substance that has a structure which causes the oil to become more viscous (thicker) at lower temperatures, Swank explained. Glycerin itself is composed of a glycerol "head" with three fatty acid "tails." These tails can tangle up with each other at lower temperatures, causing the increase in viscosity.

By adding methanol and lye (sodium hydroxide) to vegetable oil, the glycerol "head" is cut off, freeing the fatty acid "tails" and decreasing the chance that they will entangle at low temperatures.

The glycerol and lye sink to the bottom, and the remaining fatty acid chain solution—now termed biodiesel—rises to the top. The solution can remain liquid at low temperatures just like petroleum diesel, making it completely interchangeable for use in diesel engines.

And what of the glycerol "waste" produced in the process? It can be reused, Swank said, since it is a major component of many soaps.

Transferring Awareness Into Action

Of the 13 BioBus members, only 12 are making the arduous road trip. The team's days days often start before dawn and end well after midnight. College senior Lindsey Corbin, a geography and economics major, chose to stay behind for a very important reason.

"I think that in order to transfer awareness into tangible results and change … [it] takes follow-up … [to] sustain that energy," Corbin said. To this end, she assists interested faculty and students in forming panels to study the most effective ways to integrate biodiesel use at their schools.

"People are really, really excited," Corbin said. "I think a lot of the students—they don't know that an alternative could be feasible." So feasible, in fact, that some schools are considering building on-site biodiesel refineries or installing their own tanks for distributors.

Corbin herself will study alternative fuels as they apply to different geographic regions for her independent senior project. She credits her involvement with BioBus for helping fuel her career aspirations in the alternative-energy field. "I think that personal experience probably had the biggest impact on me," she said.

As for the remaining 12 BioBus road warriors, they have a long way to go before they sleep each night.

The team has already presented the bus at Columbia University and NYU in New York City, National Geographic Society headquarters in Washington, D.C., Michigan State University in Detroit, and the Museum of Industry and Technology in Chicago. They are now headed for Lincoln, Nebraska.

"It's harder than school, I think," Stephen Swank, who plans to study medicine, said of the rigors of their trip. "And Middlebury is tough."

The team divides up daily duties. Tasks include driving the bus, locating fuel stops, giving interviews and presentations, researching questions posted to their Web site, and keeping in touch with staff at upcoming exhibition sites.

"We're a pretty well-oiled machine," Swank said. "Veggie-oiled."

For BioBus members and an energy-hungry public alike, that just might be the key.

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