From fish fry Friday frying oil to fossil fuel free bio-diesel, the Moosejaw Pizza and Dells Brewing Co. got creative this summer while trying to find a way to keep down delivery costs amid rising fuel prices.

Although the situation doesn't seem as dire now that gasoline prices are under $2 and diesel fuel is less than $2.50 a gallon, that wasn't the case this summer.

In Wisconsin the average price for a gallon of diesel fuel peaked this summer at $4.78 per gallon, according to AAA.

With two of its four delivery vehicles — both Volkswagen Beetles — running on the high-priced black gold, Moosejaw Owner Mark Schmitz decided that it was time to look into an alternative source of vehicle propulsion.

"It was something I saw on TV a long time ago," he said. "It really perked my interest. And it came to fruition this summer when oil went through the roof."

What Schmitz saw on TV was diesel-engined cars running on bio-diesel, something that can be derived from many kinds of oils including peanut and vegetable oil.

Instead of paying nearly $5 a gallon for diesel and paying a company to haul away the restaurant's used vegetable oil, Schmitz decided to use the vegetable oil to make bio-diesel.

Schmitz said the conversion process for turning the used vegetable oil into usable fuel is simple enough, and no car modifications are needed to use bio-diesel.

The vegetable oil must first be filtered to remove things like food particles. It is then heated to approximately 140 degrees Fahrenheit for further purification.

Then, a combination of lye and methanol is carefully added to the filtered oil and is allowed to mix for eight to 12 hours, Schmitz said.

The entire process takes about two or three days, but the end result is a completely biodegradable, non-toxic and renewable source of fuel.

Straight vegetable oil can also be used to power diesel engines but modifications including a heating system and additional filters are needed to keep the oil from harming the car.

According to the National Bio-Diesel Board, an association that coordinates bio-diesel research and development in the U.S., raw vegetable oil is not registered with the Environmental Protection Agency and is not a legal motor fuel.

Moosejaw's "Bio-Bugs" can also run on diesel, but Schmitz said he can make enough bio-diesel to run both cars all year long.

The cars do run on diesel from December through March, Schmitz said, because of Wisconsin's cold temperatures. The vegetable oil would gel in the cars if it were used during the winter and wasn't kept warm.

"I was amazed the first time that it worked," Schmitz said.

At first, he said he thought he had ruined the car because the bio-diesel wouldn't light on fire like diesel does. He learned, however, that bio-diesel is non-flammable and works because of high compression.

Moosejaw started using bio-diesel for its Beetles in June, and Schmitz said the cars get the same gas mileage on bio-diesel — approximately 45 miles per gallon — as they do on diesel.

Probably the best part about the bio-diesel is how much it costs. Schmitz said he can make a gallon of bio-diesel for about 70 cents.

According to the National Bio-Diesel Board, bio-diesel is better for the environment, too, because it releases less toxins into the air.

Schmitz said the exhaust emissions are so people friendly that someone could stick their nose right up next to the muffler, and the only side effect would be that they would smell like french fries.

Moosejaw has two other delivery vehicles, both PT Cruisers, that run on unleaded gasoline.

"If they had diesel engines for them (the PT Cruisers), I'd change them out in a second," Schmitz said.

Moosejaw and Schmitz's other property, Buffalo Phil's, might some day have a full fleet of Bio-Bugs, but for now Schmitz must settle for the two.

The bugs are still being used and will soon be topped with Moosejaw's distinctive moose.

Schmitz said his favorite part about the Bio-Bugs isn't their great mileage, but how they have affected his driving habits.

"My favorite part is that I can drive right past the gas station," he said.

Using forms of bio-diesel to run diesel engines is nothing new. Engine designer Rudolf Diesel ran his first diesel engine on peanut oil in the early 1900s.

Moosejaw's ultimate goal in the switch to bio-diesel is to simply be self-sufficient.

"We are looking forward to independence from fossil fuels," Schmitz said.