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September 14, 2006

Undergrad researcher slips past high gas prices

High prices at the gas pumps have caused many a driver to cringe at the thought of filling up, but one Pitt student is cruising without a care in the world: He’s driving for free in a car powered by vegetable oil.

This summer, sophomore Pat Lambert converted a diesel-powered 1984 Mercedes 300 SD to run on either diesel or vegetable oil in a bid to discover how feasible the option might be for the average Joe who wants to cut his fuel bills.

Converting diesel engines to run on alternative fuel isn’t new. But vegetable oil (VO)-powered cars are novel enough that there’s little practical information available for those who want to analyze the costs and benefits of a conversion.

Under the guidance of chemistry professor Eugene Wagner, Lambert aims to fill those gaps. Lambert’s research goal, beyond the initial benefit of cutting commuting costs, is to raise awareness for VO and to answer the nuts-and-bolts questions anyone contemplating the switch needs to consider.

Wagner said little information is available for the average person who wants in-depth information on VO vs. diesel performance or how difficult and how expensive a conversion might be. “All those details someone would want to know if they had an old diesel car they wanted to convert,” Wagner said.

“No one’s going to want to convert a car if it takes 100 hours, five grand and five years to pay it off,” Wagner said.

The research project has taken about 300 hours of Lambert’s time this summer, spurred on by his mentor and funded by a combined total of $4,300 from the Honors College and the School of Arts and Sciences’ Office of Experiential Learning.

Lambert took charge of the project with minimal assistance, Wagner said, clearly impressed with the student’s drive and passion for the project. “He’s essentially the PI,” Wagner noted, adding that his own role was more that of guidance counselor — opening doors and presenting Lambert with options.

“It really didn’t take any pushing,” Wagner said. “It was something that he really wanted to do.”

It didn’t matter that the definitely nontraditional research project might be seen as an engineering endeavor, or that Lambert isn’t a chemistry major, Wagner said. “He’s almost a poster child for what someone can do at Pitt. … Ultimately if you have the drive to do research, there are resources at Pitt to help you do that.”

Wagner said if a student approaches with a project, his goal is to help the student figure out what it will take to accomplish it.

“This one with Pat just came about because we talked a bunch and had that common interest in cars.”

From the outside, the car looks like any other well-aged vehicle for a student on a budget: mismatched black and gray thanks to replacement parts that attest to the car’s 237,000 mile history; patches of rust, one of which Lambert’s friends tease looks like a gunshot.

A closer look reveals an unusual license plate frame that reads, “I burn used veggie oil,” a gift from Lambert’s dad, who partnered in the conversion project. A deep breath near the exhaust reveals the ever-so-slight hint of eau de fryer.

“The smell of exhaust is a little like Chinese food,” Lambert admits.

Thanks to a restaurateur friend, the car is fueled by used cooking oil Lambert collects from several local Chinese eateries, then filters at home. “I haven’t paid one red cent for oil yet,” he brags.

Inside the trunk, a custom-made 24-gallon aluminum fuel tank is joined by a fuel pump, two heat exchangers and an onboard oil filtration unit. An important part of getting the oil to burn efficiently is to warm it on its way to the engine to reduce viscosity. As insurance against cold Pittsburgh winters that could thicken the oil, Lambert has added an electric pad heater — yet to be put to the test — to warm the tank when needed.

“The more you heat your oil, the better your emissions are,” Lambert said, adding that the fuel is about 170 degrees Fahrenheit when it reaches the engine.

Under the hood, a quick inspection reveals few additions beyond an extra fuel line and the last of three heat exchangers that warm the VO on its way to the engine.

Switches that allow Lambert to shift between diesel and VO and a few gauges are the only additions to the car’s interior.

The project got underway with the car conversion, which took several solid days of work and about $2,000 to complete. “The first day, it started right up,” Lambert said, surprised that there were so few bugs in the process and only a few small leaks that quickly were remedied.

Since then, Lambert has logged about 4,000 miles on the car, more than 800 of them under VO power. He’s already discovered his fuel performance is nearly equivalent to conventional diesel: He gets about 30 miles to the gallon with either fuel, he said.

Now he’s compiling data on the practicality of the conversion and documenting emissions and reliability issues. The experiment is ongoing: “I have to see how well this will work in the wintertime,” he said. Faculty member Wagner said once the data is compiled, it will be posted online.

Getting the word out on VO is important, Lambert said, noting that although plenty of people know about biodiesel thanks to singer Willie Nelson’s support for the fat-based fuel, fewer people are aware that engines can be run on plain VO.

The difference between biodiesel and VO is that biodiesel must be processed in order to separate the usable fuel. No engine conversion is needed, as is the case with VO.

“VO cars more typically are done by garage gearhead people who just think it’s cool to drive a car cross country and not pay anything,” Wagner said. “Is one better than the other? The verdict’s still out.”

While VO may never become mainstream, Wagner said it could have value for a business owner with a small fleet of vehicles or as an inexpensive source of fuel to power generators at schools or hospitals.

And, if an automaker would offer a VO-capable engine as a factory option, or garages offering one-day conversions sprang up, the idea could take off.

“If it becomes easy, people will do it,” Wagner contends.

The wheels continue to turn in Lambert’s imagination. He’s hoping to convince the University to follow in his tire tracks and convert a shuttle bus to VO. He estimated that the campus shuttles use about $150,000 in fuel each school year, a cost that could be eliminated by converting to VO, since there are ready sources of fryer oil in the dining halls and restaurants on campus.

About 840 gallons of cooking oil are used each week on campus, said Beth Plocki of food service provider Sodexho.

Wagner is on board with the idea. “If they would convert just one bus, make it the ‘green bus,’ it would be great PR for the University — environmentally conscious, forward thinking,” he said. “Students would get a kick out of riding the green bus.”

Lambert agrees with his professor. “Being green, not paying for gas and not outsourcing fuel from other countries comes together here. It seems too good to be true.”

“The whole idea is to use an energy source that’s free,” Wagner said, “I like the clean idea of vegetable oil. The whole idea makes sense. Everybody wins.”

—Kimberly K. Barlow

Filed under: Feature,Volume 39 Issue 2

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