Flower Power

Brad Callos
September 01, 1999

Imagine a car that runs on sunflowers—a car that doesn’t cause smog or rely on foreign oil. Sounds like a Sixties daydream, right?

drawing of yellow sunflower

But for Joseph Perez and Andre Boehman these aren't just dreams. Perez, a chemical engineer, and Boehman, a mechanical engineer, are working out the knocks in an engine system that runs purely on vegetable-based oils. "Our initial goal is to reduce the emissions from passenger vehicles," Boehman says. "But our work has applications for all combustion engines." Their research began in 1995 when both professors came to Penn State.

Perez, who graduated from the University in 1964, ended his retirement in order to study new innovations in tribology, the study of lubricants. (Tribology is derived from the Greek word tribos, which means rubbing.) In his lab, he tests a variety of lubricants. The most promising is HOSO (High Oleic Sunflower Oil). "At this point we're concentrating on additives to improve its performance," Perez explains. "By mixing it with a little ester, we've found a nice balance."

According to Boehman, there are many reasons to choose biolubes—biological lubricants—over petroleum-based alternatives. "High Oleic Sunflower Oil approaches the performance of synthetic oils," he notes. "And it is still in development." Better performance means more than a smoother ride or less engine noise. High Oleic Sunflower Oil also has lower emissions, better fuel economy, less engine wear, and lower particulate mass than petroleum.

Particulate mass is one major indicator of the amount of pollutants produced by an engine: The goop from unburned fuel and oil collects on the surface of particles of soot formed in the cylinder of a diesel engine. As the particles accumulate, the oil thickens and friction increases—and the engine needs more fuel to keep up to speed. Eventually, the particles are expelled through the exhaust system, where they often collect as they cool. Again, they present a problem: This time it's more like cholesterol in a hardening artery, blocking the flow of normal engine waste. Build-up of particulate mass—that dark, smoky diesel exhaust—indicates poor combustion, which means that more nasty stuff like carbon monoxide spews into the atmosphere. Boehman and Perez's study shows that using High Oleic Sunflower Oil significantly decreases the production of particulate mass under light-load conditions. Overall, the biolube produced only a third as much goop as was produced by petroleum lubricants under the test conditions.

Another ecological benefit is that High Oleic Sunflower Oil is 80-percent biodegradable. That's over 250 percent better than standard petroleum lubricants. It is also easier to landfill, because it doesn't contain any of the possibly carcinogenic hydrocarbons found in petroleum. "Of course," Boehman adds, "this stuff will burn cleanly in oil furnaces after it's been through an engine." So disposal may not be much of an issue.

Remember, it comes from sunflower seeds. It's renewable. This veggie oil could decrease the need for petroleum drilling and promote homegrown industries. "But lubricants are big business," Perez cautions. "And High Oleic Sunflower Oil is still twice as expensive as petroleum lubricants." Based on performance, HOSO is priced right. Its cost mirrors performance when compared to both petroleum and synthetic lubes. "However," Perez notes, "the supply required to replace all lubricants is inadequate."

Testing is still under way. Many companies are working to genetically engineer sunflowers to produce less-saturated oils. These altered plants could lower the cost and increase the yield of High Oleic Sunflower Oil. Many experts speculate that vegetable lubricants will gain popularity as mineral oils become scarcer.

"High Oleic Sunflower Oil may make its first impact in places where pollution is a major concern," Perez notes. "Motorboats and forestry vehicles are coming under greater regulation." In Germany, Sweden, and Denmark, rapeseed and canola oil lubricants are already mandated for use in these industries. "U.S. automakers must continually meet tougher standards for fuel efficiency," Perez adds. High Oleic Sunflower Oil may offer them a solution. General Motors, Navastar, Texaco, and Volkswagen are just a few companies interested in new lubricants. Because High Oleic Sunflower Oil runs in contemporary engines, many in the industry are optimistic about its potential to improve engine efficiency. Boehman is working on a retrofit kit that will enable any mechanic to optimize old engines for High Oleic Sunflower Oil. He'll test his new kit this fall, converting a campus shuttle bus to test biolubes and biofuels. "We hope to take an old, dirty bus and make it run cleaner," Boehman says.

Joseph Perez, Ph.D., is adjunct professor of tribology in the College of Engineering, 105 Fenske Lab, University Park, PA 16802; 814-865-0340; jmp13@psu.edu. Andre Boehman, Ph.D., directs the Combustion Laboratory and is assistant professor of fuel science in the College of Earth and Mineral Sciences, 114B Hosler Bldg., University Park PA 16802; 814-865-7839; alb11@psu.edu. Their research has been funded by Renewable Lubricants Inc. and Caterpillar, Inc. Students working on the project are currently funded by the Royal Thai Government (Thailand) and the USDA's National Center for Agricultural Utilization Research.

Last Updated September 01, 1999