Breakthrough could make biodiesel commercially viable

What's all this about? In today's Letters to the Editor of the Sydney Morning Herald:

I read of various politicians pressing for the legislated inclusion of ethanol in petrol. Shouldn't they instead be calling for the use of the new technology announced by the University of Wisconsin that produces high-grade diesel from plants?

It was reported to be twice as efficient as ethanol production.

Chris Horn Summer Hill

I Googled myself up some encouraging news. It seems these University of Wisconsin scientists believe they are not far off the point where producing biofuels will be cost competitive to petrofuels:

Eco-dreamers have long hoped for a way to drive around without contributing to global warming, but the slow pace of progress in alternative fuel technologies has kept that vision from materializing. Now, a promising new process, designed by researchers at the University of Wisconsin and outlined in a paper that appeared in the journal Science on June 2, could be a significant step toward turning that dream into a reality.

The paper details a new way to produce biodiesel fuel, which is made out of plant matter. Traditional biodiesel refining uses only the fatty acids of a plant, which typically make up less than 10 percent of the mass of dried plants. Rather than converting only the fat, this new method promises to turn all of the dried plant material, including roots, stems, leaves, and fruit, into biodiesel or heat energy.

Ethanol, the most popular and commercial biofuel, has long been refined out of plant matter, but it requires the costly, energy-intensive step of distilling every molecule of water out of the solution. In contrast, the new biodiesel process is based on aqueous phase reactions, which don't need to go through the expensive distillation phase.

"The biggest advance we have to offer is the lack of that distillation process," says George Huber, one of the paper's authors and a graduate student at the University of Wisconsin who will soon be teaching at the University of Massachusetts at Amherst. "That means that our process is exothermic." In other words, it doesn't need a lot of extra energy. And that's important, because the largest cost in the current biofuel refining process is energy.