Soaring energy prices pushed Rick Harrison into action. Now, by putting his know-how to work, he's paying just about 75 cents a gallon for fuel.

Harrison is making his own biodiesel fuel.

At first glance, the process has Rick looking like a mad scientist at work in his garage, measuring and mixing -- but the result puts money in his pocket.

"When you do the math, it's hard to understand why anybody wouldn't do it," he says.

The process begins with the barrels in the kitchens of two local restaurants. When they're done with their fry oil, they dump it in and Rick picks it up.

Back in his garage, he heats the oil, calculates how much lye and methanol to mix in, puts the mixture in a hot water heater turned "reactor" and then runs water through it to remove the impurities. Then it goes in the fuel tank.

Converting diesel engines to run on vegetable oil has been catching on in recent years but this is different. Running on pure vegetable oil requires an expensive modification to the vehicle's engine. Rick's chemistry converts the fuel, not the truck.

He says, "Six hours, every couple of weeks -- I can produce 50 to 60 gallons of fuel. That's about what we use on the norm."

The savings for every batch: $117. And Harrison says the science is not complicated.

"You say titration and it scares a lot of people away. I was like that too," Rick says. "But once you do it a couple of times, it's a piece of cake. There's nothing to it."

Biodiesel is classified non-flammable by the Environmental Protection Agency. It's only volatile under the extreme pressure exerted inside a diesel engine block.

Rick says, "You could strike all the matches you want. It wouldn't do anything but put the match out."

There are some drawbacks. Biodiesel does not work well in cold weather. And even though he makes his own fuel, Rick still has to pay the state fuel tax every three months but he says it's worth it.

Aside from the savings, biodiesel emissions are far lower than regular diesel.

Harrison's hobby is turning into a side business. He's helping interested people get the materials and he's designed a computer program to help with the chemistry.

An important reminder with all this: it's for diesel powered vehicles only. It's not gasoline. Rick recommends checking with your car dealer to see if using biodiesel will affect the vehicle's warranty.

The process goes something like this. Rick collects used vegetable oil from two local restaurants. They'd usually have to pay someone to haul it away, so it's a benefit for them too.

He then takes the oil (in 55 gallon drums) to his garage where he heats it and does a basic chemical test (similar to checking the ph of pool water) to find out its acid content. That tells him how much lye and methanol to add.

Those ingredients are mixed with the oil in a hot water heater. The mixture is then pumped through a ''wash'' tank. The water carries away impurities. The fuel is then added to a "dryer" that pulls out any remaining water. It goes from there into the tank of his truck.

Unlike people running their cars on pure vegetable oil, this requires no modification to the engine. Converting a diesel to run on vegetable oil costs upwards of $1,000. The equipment Rick uses can be purchased at a hardware store for around $600. And he can still run the truck on regular diesel if he needs to. That's important in the winter because bio-diesel does not do well below freezing. It can be mixed with petro-diesel to lower its freezing point.

There is a by-product to the process: glycerin. Rick dries the glycerin and makes soap out of it. A lot of soap.

Rick's hobby has turned into a business. He started Omaha Biodiesel to help others get started. Because of the astronomical fees, regulations, and red tape associated with selling fuel, he's only selling supplies. He's also speaking at lectures aimed at getting Co-Ops started. A fuel Co-Op would do what he does in his garage but on a larger scale with more people sharing the cost and the fuel.

There's more information on biodiesel on the EPA Web site. Click here for the pdf file.