Can We Finally Make Gasoline out of Corncobs?

by Nathanael Johnson (Grist) ... Running cars and planes on corncobs would, at its best, produce 90 percent less greenhouse gas than gasoline.

Until now, though, it’s only been an idea. We’ve been able to make cellulosic ethanol for more than a century, but not efficiently or economically. We’ve only produced a tiny trickle, and it’s been ridiculously expensive. So news that two commercial-scale cellulosic plants have opened in Iowa, after a decade in which half a dozen failed to reach full production, made me wonder: Has that changed? Is the dream of fueling cars with corn husks finally a reality?

To investigate, I went not to Iowa, but to Silicon Valley, where the technology behind cellulosic ethanol is being tested and, perhaps, perfected. One of the biggest players in the ethanol game is the chemical giant DuPont.

Cellulose is basically fiber — think corncobs, grass stems, and woody branches. Farmers frequently rake it away, sell it cheap, or burn it. Some of this plant material should stay on the land to act as fertilizer, but the best research suggests that farmers can take as much as half away to make fuel without hurting the soil.

What’s taking so damn long? That’s what I asked Chris Somerville, director of the Energy Biosciences Institute at the University of California, Berkeley. A tall grandfatherly man with a white moustache and a soft voice, Somerville acknowledged that the failure of the industry to come anywhere near its production goals looked bad. But he said those goals were set ridiculously high by people with no experience working with cellulosic ethanol.

If anyone’s going to tough out the effort to make cellulosic ethanol, it’s DuPont, which has a long history of sinking years into research and development before bringing a profitable and transformative product to market. “The first time we made Kevlar, it wasn’t that pretty either,” said Jan Koninckx, who is leading the company’s cellulosic ethanol push.

“There are many small improvements that we still need,” Somerville said. “And the problem with building a facility is that in a decade it will be obsolete. But there’s only so much you can learn from small batches in the lab.” At some point, he said, you need to build a commercial-scale plant.

So that’s what they’ve done in a small Iowa town. The steady grind of progress continues. If companies keep that up, we’ll see the trickle of cellulosic ethanol grow into a river. It will get cheaper and greener, and someday it will become profitable. READ MORE