Campus Lawnmowers Being Switched to Environmentally Friendly Biodiesel


OXFORD, Miss. - The scent of fresh-cut grass may be accompanied by the aroma of fried catfish, chicken or potatoes at the University of Mississippi this summer.

The UM Landscape Services Department and Mississippi Mineral Resources Institute have joined forces to experiment with using more environmentally friendly fuel in campus lawnmowers. One mower is running on a blend of biodiesel made from used cooking oil and regular diesel, and plans call for switching all mowers to this fuel by the end of summer.

The move comes about a month after Chancellor Robert Khayat signed the American College & University Presidents' Climate Commitment. The initiative, sponsored by the Association for the Advancement of Sustainability in Higher Education, calls for colleges and universities to identify major sources of greenhouse gas emissions and reduce this output over five years.

Greenhouse gases include water vapor, carbon dioxide, methane and ozone. All are natural components of the Earth's atmosphere, but excesses of these gases cause the planet's temperature to slowly climb, contributing to what is known as the "greenhouse effect" or "global warming."

The transition to biodiesel for landscape services is the first of many changes coming to campus operations, said Jeffrey McManus, director. "We're kind of the guinea pig," he said. "We're a good group to experiment on because we have a wide variety of equipment that is used daily on campus."

For the past two weeks, the department has operated one of its riding lawnmowers on a mix of biodiesel fuel and petroleum diesel, he said. MMRI produced the biodiesel using vegetable oil offered for recycling by local restaurants.

The mixture being used is 20 percent biodiesel and 80 percent regular diesel, McManus said. The mower has operated with few problems on the blend, he said.

The long-term goal is to slowly decrease the amount of regular diesel until the machines can run on 100 percent biofuel. All of the university's mowers could be powered by a mixture of biofuel by the end of the summer, McManus said.

"People may notice a sweeter smell behind the lawnmower due to the origin of the fuel," he said. When burned, biodiesel smells like whatever was originally cooked in the oil. McManus is developing signage to put on the lawnmower indicating it runs on environmentally friendly fuel.

An industrial lawnmower may use anywhere from seven to 10 gallons of diesel fuel a day and landscaping services operates 10 to 15 mowers on a daily basis.

The department usually spends $3,000 on fuel for mowers every two or three weeks, chief mechanic David Hodge said. He also has noticed that the modified mower seems to be burning fuel at a slower rate than others but pointed out that the project is still in the testing phase.

Brad Crafton, a senior anthropology major and research assistant at MMRI, helped launch the university's biodiesel project. Crafton began experimenting with biodiesel in 2003, when he went to a university-sponsored workshop in California and learned how to make his own fuel. After returning to Oxford and working at various local restaurants, he decided to literally take his work home with him and experiment with used cooking oil.

"I knew as an anthropology major that I wanted to evaluate a need in society and try and fix that need," Crafton said. He taught himself the chemistry and made his first batches in a blender in his own kitchen.

Using the fuel should significantly reduce the air pollution the lawnmowers create, Crafton said. "Essentially, we are reducing the air pollution by 20 percent," he said.

Research indicates that biodiesel significantly reduces greenhouse gas emissions. The use of pure biodiesel can reduce emissions of carbon monoxide, sulfates and carcinogens by more than 50 percent, while the mixture adopted by Ole Miss can reduce those emissions by at least 10 percent, according to the Environmental Protection Agency's Web site

Crafton creates the fuel in an MMRI facility in Oxford using an industrial grade, computer-controlled processor that "makes very high quality fuel," he said. This is an upgrade from the original 35-gallon biodiesel processor he built himself for less than $1,000, using a modified 40-gallon water heater, a 70-gallon cone-shaped settling tank, a 120-gallon washing tank and several hoses with quick-release valves.

Crafton runs his own 1980s Mercedes Benz on 100 percent biodiesel in the warm seasons and a 50 percent mixture in the winter. He can produce the fuel for $1 a gallon provided local restaurants continue to donate the used cooking oil.

"Most restaurants pay to have that stuff hauled off," he said. "So this way they save on a bill and I save on a bill."

The university uses several diesel vehicles, so this technology could save Ole Miss a considerable amount of money, in addition to reducing air pollution. MMRI has been running its 15-passenger van for more than a year on pure biodiesel with no mechanical problems.

Though Crafton operates a small-batch facility, he's confident the production will be able to grow to meet the university's needs. The fuel has been evaluated and meets both ASTM and EPA standards.

For more information about the Mississippi Mineral Research Institute, visit

by Andrew Abernathy

Newsdesk Story #7055