Coffee can rev your engine. Really.
Rebecca Clontz, an environmental science graduate student at RIT, is converting coffee grounds into a biodiesel-espresso for cars.
“I want to get a bumper sticker that says, ‘I run on coffee,’” said Clontz, a native of Athens, Tenn.
Clontz and her thesis adviser, Jeff Lodge, associate professor in RIT’s Thomas H. Gosnell School of Life Sciences, are exploring the potential of turning food waste into energy on a local level. They started by asking coffee shops on the RIT campus to donate their grounds every day in August. Employees at Artesano Bakery & Café, Beanz, Java Wally’s and Midnight Oil helped Clontz collect 150 gallons of used coffee grounds during one of the slowest months on campus.
“I washed out two buckets and put a sign on it that said, ‘Coffee grounds for biofuel,’ and I showed the managers the scientific paper I was trying to emulate,” Clontz said.
Scientists from the University of Nevada, Reno, published the study that inspired Clontz’s thesis research. Lodge suggested the project after reading about the new lipid, or oil, the researchers extracted from Starbucks coffee to make biodiesel. The multitude of coffee houses across the United States adding coffee grounds to landfills caught his imagination.
“I started thinking large,” Lodge said. “What do all the Starbucks do with their grounds? And then it struck me—because my kids got me a Keurig for Christmas last year—and I started thinking, ‘Wait a minute, what about all the Keurigs?’ They’re everywhere. And where is all that going?”
Lodge spent a month cutting up the little disposable plastic containers and removing the grounds to add to Clontz’s study.
To expedite their research, Clontz and Lodge purchased a large drying oven and rotary evaporator with seed funding from a $15,000 Dean’s Research Initiative Grant from the College of Science. The grant, awarded in the fall, supports Clontz’s research this semester and provides travel money to present her findings at an energy conference.
“I’m extracting the oils from the dried coffee grounds and converting that to a biofuel and extracting the glucose and converting that to ethanol,” Clontz said.
During the intersession break, Clontz and Lodge conducted a scaled-down version of the commercial method to make biodiesel from 250 milliliters of oil extracted from the campus coffee grounds.
Biodiesel produced from coffee and algae—a second energy source Clontz is exploring—is a “drop-in fuel” that won’t corrode a car’s engine, Lodge said. “It’s a cleaner burning fuel,” he said. “It’s not perfect, but it is cleaner.”
Clontz’s thesis is about sustainability and uses “anything and everything” for multiple processes, Lodge said.
“It’s carbon neutral,” Clontz added. “The carbon removed from the atmosphere in growing the coffee is the same carbon released as a fuel.”
Even the leftover coffee grounds will find another use as compost and an organic fertilizer. Clontz will grow plants in it this spring in the greenhouse attached to Gosnell Hall and compare it to fertilizer derived from algae.
“The coffee grounds are not going to a landfill and that’s a huge thing,” Clontz said. “We’re going to use everything and compost at the end. It’s exciting.”