The same oil used on the Danforth Campus to make french fries is powering a truck near you.
Used vegetable oil from WUSTL Dining Services kitchens is being reused as biodiesel in a dining services vehicle on campus. Through the program, which began in November, WUSTL Dining Services is partnering with St. Louis company Kelley Green Biofuel to prevent approximately 150 gallons of waste vegetable oil each week from ending up in a landfill. Instead, the cooking oil will be used as fuel in a dining services truck.
Cooking oil is collected at three campus locations: the Village House, Mallinckrodt Student Center and the South 40 House. After cleaning the vegetable oil and converting it into biodiesel, Kelley Green — founded by Kristopher Kelley, a 2008 WUSTL alumnus in Arts & Sciences — returns the oil to a 300-gallon holding tank at North Campus.
According to Jill Duncan, dining services marketing director, plans are eventually to expand the program to fuel other dining services vehicles.
"Sustainability is the cornerstone of our dining philosophy at Washington University," Duncan said. "For years, we have purchased directly from small owner-operated local farmers; served seasonal, responsibly sourced food; and focused on reducing our carbon emissions.
"This biodiesel program takes us one step further in our quest to make our environmental footprint as small as possible while providing delicious food for our guests," Duncan said.
To create biofuel from used vegetable oil, Kelley Green first cleans the used vegetable oil to remove the food sediment and water. Next, sodium hydroxide (lye) and methanol are mixed with the oil to remove the glycerin.
Before the fuel is returned to the campus, Kelley Green adds a portion of petroleum diesel — the amount depends on the season, with more being required in the winter, when it's cool, and less in the summer, when it's warm.
This process allows the final product to run in any diesel engine without modifying the engine.
One gallon of waste vegetable oil yields about one gallon of biofuel, which, in turn, has a comparable energy content to one gallon of petroleum diesel.
During the process, Kelley Green stores the oil in salvaged tanks. Kelley Green's refinery was built with almost entirely recycled materials.
The biodiesel program at Washington University is one of many steps toward environmental sustainability taken by WUSTL Dining Services and Bon Appetit Management Co., the contractor that provides dining services on the Danforth Campus. In 2007, Bon Appetit launched its Low Carbon Diet, which pledged to reduce the company's carbon emissions by 25 percent by 2010.
At WUSTL, sustainable practices by dining services include using local products when possible, showing the connections between food choices and climate change and serving only sustainable seafood.