Zoo train will be partially fueled by french-fry grease

The iconic train at the Cincinnati Zoo is about to become a shade greener.

A new user-friendly vegetable oil-to-biodiesel converter designed by UC Engineering seniors will start turning the waste oil from four zoo restaurant's fryers into biodiesel next week. The bulk of the fuel will be blended with the petroleum diesel that currently powers the train.

The program is one of many energy-saving initiatives that the Cincinnati Zoo has enacted in the past couple of years, and one of four energy projects by UC engineering students that will be on display at the Technology Expo and Energy Conference in downtown Cincinnati on May 4.

Mechanical Engineering and Technology (MET) senior Jamie Judd built a cart with a tank and pump that will collect the grease, and her partners Lawrence Nurre and Jonathan Meyer built a "homebrew" style reactor out of hot water heaters and plastic tanks that will convert the used vegetable oil into biodiesel. The unit also captures methanol, a byproduct of the reaction. While most "homebrew" operations are time-intensive, the students automated a few steps to create a user-friendly system for Zoo employees, Meyer said.

Like many green initiatives gaining ground around the country, the biodiesel program will boost the zoo's bottom line as well as its image.

The converted biodiesel will cost about $1.40 to $1.50 per gallon after labor and materials are factored in, which is about half the price of biodiesel, Meyer said. The only thing preventing the Zoo from saving even more money is the limited supply of waste vegetable oil that it produces - about 25 gallons per week during its busiest season.

Meyer estimated the project's material cost to be around $4,000, and said it should pay for itself in less than five years through reduced fuel costs and money saved on grease removal.

The biodiesel converter is one of four energy-related projects produced by engineering seniors this year, UC professor and physical plant director Ray Miller said. The other projects include an energy audit for arts groups like the Aronoff Center for the Arts, a project that recycles paper into pellet fuel and a home wind turbine kit that could be sold at a hardware store.

All four of the projects will be on display at the Energy Expo, today Tuesday May 4.

Writer: Henry Sweets
Sources: Jamie Judd, Jonathan Meyer, Ray Miller