By Andrea Quong

Hog fat. Triglycerides. Cooking grease. Algae oil. These are among the latest ingredients being cooked up in what a team of researchers at North Carolina State University (NCSU), Raleigh, hope will become a green alternative to petroleum-based jet fuel.

Raleigh

The process converts low-grade fats and oils, including animal fats, into jet fuel by subjecting them to extremely high temperatures, reducing the original materials to fatty acids and removing carbon dioxide from those acids. Those fatty acids, called alkanes, are then reformed into the hundreds of different molecules that comprise jet fuel.

The result could be a cleaner-burning, renewable aviation fuel that releases far less soot and harmful pollutants into the great BIG blue than conventional, petroleum-based fuels, said project leader and NCSU aerospace engineering professor Bill Roberts. The low quality animal fats and oils that would be used to make this bio-jet fuel are 30 percent cheaper than the virgin vegetable oils commonly used in automotive biofuels, Mr. Roberts said.

“You’re not competing with food supply,” Mr. Roberts said of pig and other animal fats. “Most of it’s going now to cosmetics and dog food.”

But how viable is it? The U.S. only produces one-and-a-half billion gallons of animal fats every year. That’s a far cry from what would be needed to quench our thirst for global jet-setting. According to the Federal Aviation Administration, U.S. commercial jetliners gobbled up some 24.5 billion gallons of fuel in 2006 alone. The only real alternative to date is a kind of synthetic jet fuel that’s being tested out by the U.S. Air Force and a South African airline, Mr. Roberts said. But that petroleum substitute is based on coal.

U.S.

Fat-derived jet fuel could be produced as long as most people don’t turn into vegetarians. Scientifically, it seems feasible, according to DTN analyst Rick Kment. Glycerol, a by-product of the process, for example, would be recycled and burned to generate the high temperatures needed to create the stuff.

“It’s a processing issue,” says Kment. “It’s not a huge stretch to really develop a lot of the oils or animal fats that are used in the biodiesel process for jet fuel. The question is: Is this going to be commercially, economically viable to utilize these products at this price?”

For the moment, the technology is based on an experiment with a few teaspoons of fat, and Mr. Roberts said it could take up to five years to get to the pilot production stage. Still, there’s promise enough.In February, the Gilbert, Arizona-based renewable fuels firm, Diversified Energy Corporation, licensed the technology.