Bio-fuels are a hot topic with gasoline prices cruising close to the $3 mark at times. Students at Kettering University have found a way to cut their fuel costs and ride the cutting edge of bio-fuels - by burning used doughnut frying oil in their re-engineered Volkswagen diesel Rabbits.

The students, Justin Keiffer, of Carson City Mich., Brian Kulling, of White Lake, Mich., and Jake Hirschman, of Alma, Mich., have formed an informal partnership with two other students to develop and improve their technique of re-engineering the Rabbits to burn 100 percent vegetable oil.

They have also entered into an informal agreement with Bosch to test bio-diesel fuels on a test engine at Kettering under the supervision of Dr. Greg Davis, professor of Mechanical Engineering, and Ray Rust, senior lab coordinator in Mechanical Engineering. Bosch is a multi-national company providing automotive technology products like gasoline, diesel and chassis systems and car electronics.

"Right now we are using straight vegetable oil and are working on making our own bio-diesel fuel for use in our vehicles," said Keiffer, the first of the group to buy a diesel Rabbit with a view toward making it a bio-diesel vehicle. Bio-diesel fuel is a modified vegetable oil, so it doesn't need to be heated (like 100 percent vegetable oil), to be run through a diesel engine.

"I bought the first one a little over a year ago as a Rush vehicle (all three are members of Sigma Chi Fraternity at Kettering)," said Keiffer, "when I finally got it running it was just in time to give my other vehicle to my little sister. It just so happened that was right before the fuel hikes so I looked like a genius with my fuel savings," he said.

He first learned about refitting diesel vehicles from a book called "From the Fryer to the Fuel Tank: The Complete Guide to Using Vegetable Oil as an Alternative Fuel" by Joshua Tickell, Kaia Tickell and Kaia Roman, and through other resources he found on the Internet.

It took Keiffer almost six months to get all of the components to adapt the car to run on straight vegetable oil (new or used). The most expensive parts were the steel for the vegetable oil tank and the selector (the valve that allows him to switch the engine from running diesel fuel to vegetable oil), they were $60 each.

He now gets used cooking oil from the Village Market Bakery in his hometown of Carson City. Not only does he drive it for fuel savings, but he, Kulling and Hirschman use it in tests for their independent research in bio-diesel fuels.

Kulling bought his 1981 VW Rabbit because he wanted to experiment with vegetable oil after seeing what Justin was doing. "I wanted to do it also, and see if any improvements could be made on the system," Kulling said.

Although he was the last to hop on the "Rabbit wagon," Hirschman is closer to completing the alterations necessary to burning vegetable oil than Kulling. "My Rabbit was just more complete when I bought it," said Hirschman. "I really wanted to save on gas and it went along well with my interest in diesel engines and bio-diesel fuel. My co-op job is with Bosch, which is big into diesel products. I get an extra 25 dollars a month just for driving a diesel to work," he said.

Protégés of Davis, who specializes in alternative and bio-fuels, the trio are also getting academic credit for converting their cars to bio-diesel in the form of independent study credit.

Bio-fuels have been developed for both gasoline-powered and diesel fueled engines, according to Davis. "Both types of fuel reduce greenhouse gas emissions and provide a path toward sustainable energy use in the future," he said.

"On the diesel side, bio-diesel can be produced from any vegetable oil source," Davis said. "Chiefly, in this country, we use rape seed oil, or soybean oil, and bio-diesel, like ethanol (in gasoline engines), reduces most emissions."

Bio-diesel fuels generally come in three strengths: B2 (2 percent bio-diesel and 98 percent petroleum-based diesel) B20, B100 (made from 100 percent vegetable oil). At the B20 level bio-diesel reduces most emissions by about 15 percent, while increasing NOx by about 2 percent. NOx is a byproduct of combustion engines caused when the nitrogen and oxygen in air react to high temperature in combustion engines forming particulate matter.

"Of particular importance is the ability of bio-diesel fuel to produce a large reduction in particulate emissions (PM)," said Davis. "PM is the 'smoke' often associated with diesel engines and is one of the reasons for the limited use of diesel engines in the U.S. B100 can reduce PM by about 50 percent and it provides about the same performance as conventional diesel," he added.

Keiffer, Kulling and Hirschman can attest to that. Keiffer is averaging between 43 and 51 miles per gallon with a top cruising speed of about 70 miles per hour, and, "there is less smoke coming out of the exhaust." Kulling and Hirschman both said they average about 50 miles to the gallon using vegetable oil. Their vehicles' performance on vegetable oil is similar to that of regular diesel engines, they said.

If there are side effects to running used doughnut oil through an engine, they would be both good and bad; one being a cleaner fuel system and the other being faster degradation in older hoses that experience prolonged exposure to vegetable oil, but "there are newer rubbers and plastics that are not affected by bio-diesel fuels," said Keiffer. "I have heard that some of the newer style diesels (direct injection engines) can be a little touchy but I have no experience with these engines," he added.

Special prep work on diesel vehicles to ready them to burn bio-diesel fuel blends includes changing some fuel lines and seals, but to burn 100 percent vegetable oil a second fuel tank is needed, and the tank has to be heated to thin out the oil before running it through the engine.

"We want to research ways to heat the lines to heat up the oil faster," said Kulling, "so instead of waiting 15 to 20 minutes for the car to heat up the oil we would have a faster start up time. It would be great if we could develop a system to sell as an after market kit to allow people to retrofit their diesel vehicles," he added.

"Once the straight vegetable oil is heated up to around 180? F then you can switch tanks from the diesel (stock) tank to the vegetable oil tank," said Keiffer, "then about a mile before you shut the engine off you should switch it back to diesel fuel."

"The reason why you have to heat the oil is because it is too thick to run in an engine and heating it up makes it thinner. It's the same concept as margarine, which is mostly vegetable oil, heat it up and it goes from a spread to a liquid," he said. "The car must also run on diesel before engine shutoff to protect against any deposits forming," adding Kulling.

All the re-fitting and engine switching is worth it for a savings of more than $1,600 so far this year. "I've run my car more than 1,600 miles this year on vegetable oil and saved more than $1,600 in fuel costs since January," said Keiffer. All three have, or will have, vegetable oil tanks mounted in the trunks of their cars. Part of their independent research is improving the system of switching from diesel to vegetable oil.

As to whether or not bio-diesel fuels are a practical solution to future fuel resource needs the three Mechanical Engineering majors almost agree. Keiffer doesn't think that "there is one answer to future energy sources, since the world as a whole just consumes too much. I do think that bio-fuels are an excellent partial solution."

"As for practicality, bio-fuels are great, they are renewable and the harmful emissions are far less than those of petroleum fuels," Keiffer said. Kulling agrees with that assessment, "Bio-diesel is a practical solution because we will never run out of it. But new ways of producing oil feedstock must be developed before bio-diesel can be the entire solution," Kulling said.

"What will catch on fastest is bio-diesel as a blended fuel," Kulling said. "It's already a growing movement. There are 35 bio-diesel refineries nation wide," he said.

Hirschman is throwing all his eggs in the bio-diesel basket for practicality and as the future of fuel. "I am banking on it," he said.

Written by Dawn Hibbard
810-762-9865
dhibbard@kettering.edu