Fuel that smells like French fries: Cornell produces biodiesel

If you feel hungry when you’re on campus, it might be because of one of the college’s latest efforts at sustainability. The college began converting used cooking oil from the dining hall into biodiesel to fuel campus vehicles in January, and maintenance workers say the exhaust smells just like French fries.

In the past six months, Dining Services has produced about 700 gallons of waste vegetable oil. Disposing of this oil came with a cost of about $60 for each monthly trip to the disposal site until Joel Miller, Director of Facility Services, recognized its potential.

Workers in the dining hall now strain the oil and bring it to the lab at Facility Services, which was recently constructed in a converted storage room. By incorporating reused sinks, recycled strainers, and a home-built transfer pump with a top-notch mixer and testing equipment, the overall cost of the lab was cut from about $5,000 to $3,500.

In the lab the oil is filtered and combined with methanol and lye. The amount of lye added is based on the quality of the oil: cleaner oil, less lye.

“Luckily, Bon Appétit’s oil is pretty clean,” said Ace Moore of Facility Services. After an hour of mixing and several more hours of settling, 40 gallons of oil becomes 40 gallons of biodiesel ready to be used in Cornell’s trucks, mowers, and tractors.

In 2011 the college purchased 1,780 gallons of diesel fuel at an average price of $3.43 per gallon. A gallon of Cornell’s biodiesel costs less than $2 to produce, including labor, so the biodiesel program promises to meet nearly all of the college’s diesel needs at a savings of nearly 50 percent.

Moore says the shift to biodiesel is not only cheaper, but “a lot cleaner, a lot safer, and a lot better for the environment.” In a continuation of this dedication to the environment, workers are hoping to recycle the process’ main byproduct, glycerin, to make soap.

By Margo Fritz ’15