From corn husk to bio-bus

Got gas? The buses and utility vehicles at Duke don't-at least not in the traditional sense.

Duke has been utilizing alternative fuels since the late 1990s, including biodiesel and natural gas fuels, which has helped reduce the University's impact on the environment.

"Biofuels are a brilliant solution," says Sam Hummel, Duke's environmental sustainability coordinator. "We've been working on really trying to tackle Duke's major areas of environmental impact."

One of the first alternative fuel programs at Duke was a switch in 1997 from traditional gasoline to compressed natural gas for vehicles operated by the school's Facilities Management Services. The University built a pumping station for the alternative fuel off of Buchanan St. It also investigated switching its bus fleet over to the cleaner fuel source but found that the East Campus Bridge on Campus Dr. was too low for the required fuel tanks on the roof of the school's buses.

"Compressed natural gas is much cleaner and since they are flexible vehicles, they can switch between natural gas or regular gas," Hummel says. "You don't see more cars using this because flex vehicles require a fueling station that requires natural gas, and there aren't many natural gas fueling stations."

Six years after Duke began using natural gas in some of its vehicles, the buses were still using more than 200,000 gallons of diesel fuel a year. Then in 2003, the Environmental Alliance prepared a report outlining the harmful health affects from diesel emissions. The student group won a $28,000 grant from the Triangle Clean Cities Coalition and Duke agreed to test biodiesel on two buses.

Biodiesel is a renewable fuel made from natural oils from crops like soybeans or corn or from cooking grease; it doesn't require any modifications to a standard diesel engine. Duke tested out a 20 percent biodiesel blend, which means the fuel was 20 percent biodiesel and 80 percent low sulfur diesel fuel. Transportation officials found in a seven month pilot program that the University's buses using the biodiesel emitted 18 percent less smoke and emissions than the buses using the traditional diesel. Soon afterwards Duke switched its entire fleet to biodiesel in April 2004.

"We found that although the program cost more, we were able to operate cleaner," said Peter Murphy, assistant director of Duke's Transportation Services. "The two main things we were looking at were that this was a renewable fuel and it runs cleaner."

While largely hailed as a "fuel of the future," biodiesel does have its drawbacks. Vehicles using the fuel require more maintenance on hoses and filters, Murphy said. Plus, biodiesel is more expensive and can be more difficult to procure. But the fuel switch-part of the University's increasing emphasis on being environmentally sound-has made students' daily commute just a little more Earth-friendly.


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