Want to stop paying for gas and lessen your carbon footprint? For a lump sum and a bit of elbow grease, students can be free from the power of gasoline.

What is a biodiesel car?

The typical biodiesel car has a two-tank system. One tank in the car stores diesel or gasoline, and the other tank, typically stored in the trunk, contains waste vegetable oil.

When initially started, the engine draws petroleum fuel for a few minutes until the vegetable oil is heated and flowing freely. Once the vegetable oil is ready to be used, the engine draws fuel from the vegetable-oil tank.

Two-tank systems are popular in colder climates because vegetable oil congeals in cold weather, and often needs time to warm up before it can properly burn.

Cotter Mitchell, materials lab coordinator in the department of art and design, considered making the jump to a biodiesel car for the last two years, and he said the two-tank system would be necessary for him because of the cold Kansas winters.

“You have to have a way to warm it up so it doesn’t turn into jelly,” Mitchell said.

How much does it cost to convert a car?

Greasecar.com provides customized biodiesel car kits for between $1,000 and $1,500 depending on the size of the vehicle.

Ozzie Backus, a Lawrence resident who uses alternative fuel sources to run his car, estimated that students could probably cut the cost in half by putting a kit together themselves. For the two-tank system, a separate vegetable oil tank, a pump, filter, external hoses and other supplementary parts are necessary.

How much money can you save over time?

According to the Energy Information Administration, the average American uses about 500 gallons of gasoline each year, and the average price of gasoline in 2008 was $2.69 a gallon. These figures show the average American spent $1,345 on gasoline in 2008.

Even if students purchased a preassembled biodiesel kit, it would pay for itself over time by reducing petroleum consumption.

Where can you get waste vegetable oil?

Chuck Magerl, owner of Free State Brewery, said people frequently came to Free State to get their waste vegetable oil. The restaurant stores its used peanut oil, the only cooking oil Free State uses, in a bin in the alley behind the restaurant. Magerl said the fill-up process was informal.

“A lot of people just poke their head in the back door and say ‘Hey, is it OK if I use this,’” he said.

Magerl said most restaurants downtown put their waste oil behind the restaurants as well, but he said Free State was known for the quality of its oil among biodiesel car owners.

“Something that’s made ours a little more ideal is the fact that we are using strictly peanut oil and nothing else is getting blended in there with it,” Magerl said.

He said other restaurants sometimes shared oil bins, and different types of cooking oil could get mixed together, decreasing the quality of the oil.

What materials do you need?

In addition to materials needed for a converter kit, a few tools are needed in order to pump the vegetable oil itself. Magerl said people usually used their own portable pump to fill their cars with the restaurant’s oil.

Backus said he had a 12-volt pump, which costs about $140 at biodieselwarehouse.com. Magerl said most people brought something to filter the oil before they put it into their cars. He said people found unique ways to filter the oil.

“I’ve seen things from as simplistic as a used nylon hosiery all the way up to more sophisticated poly bags and filters of that sort,” Magerl said.

No money to convert your car?

If your car already has a diesel engine, there are alternatives to the two-tank system. Backus said he had a different system of using vegetable oil in his car. He drives a Volkswagen Golf with a diesel engine. Instead of having the typical biodiesel two-tank system, he creates his own blend of biodiesel fuel.

Backus combines waste vegetable oil from restaurants with a small amount of diesel fuel and kerosene to help make the fuel more combustible. Backus said he used about two gallons of diesel for every 20 gallons of vegetable oil.

At that rate, he said he spent about $0.50-$0.60 per gallon of fuel in his car. He said that kind of system would be easy for students to manage if their car came equipped with a diesel engine. Backus said he couldn’t drive his car in the winter because he didn’t have a two-tank system.

Although this alternative fuel system worked for Backus, Dave Bach, owner of Das Autohaus, said that method could destroy diesel pumps and had negative effects on engines. Bach said running a car off a biodiesel system was not ideal but that the two-tank system was the most reliable and less likely to damage engines.

— — Edited by Andrew Wiebe