Ethanol could be on its way out this decade thanks to a discovery that makes butanol more cost-effective.
FORTUNE — In 2007 we reported on biobutanol, a biofuel with the potential to solve many of the problems associated with ethanol. Since then, industry players like BP have been seeking ways to make a cost-efficient transition to the “advanced biofuel,” and now a scientific breakthrough might finally make that possible.
Butanol trumps ethanol in several ways: Adding ethanol to gasoline reduces fuel mileage, but butanol packs almost as much energy as gas, meaning fewer fill-ups. Butanol also doesn’t damage car engines like ethanol, so more of it can be blended into gas. And because butanol doesn’t separate from gasoline in the presence of water, it can be blended right at the refinery, while ethanol has to be shipped separately from gas and blended closer to the filling station.
But with 200 plants already up and running in the U.S., ethanol is firmly entrenched. Modifying those plants to produce butanol from corn instead of ethanol costs roughly $15 million for each facility. Converting ethanol into butanol could be cheaper, theoretically, but the industry has been looking for a chemical catalyst capable of doing it efficiently. Until now, the conversion process produced too little butanol and too many unwanted products that had to be separated out. The process was “certainly too expensive to be competitive as a fuel molecule,” says Duncan Wass, a professor of chemistry at the University of Bristol in the U.K.
At the annual American Chemical Society meeting in New Orleans, Wass presented research — funded by BP BP — on a family of new catalysts that produced 95% butanol in the lab. “They hold the prospect of being able to convert ethanol to butanol in high yield, high selectivity and at large-scale,” Wass says.
It will still be some time before we’ll start seeing butanol produced with Wass’s catalysts at the pump — it takes several years just to design, build, and test new fuels at scale in a pilot plant. Wass estimates it will be six years to commercialization if the next steps go off without a hitch.
But at that point, won’t we just be trading one food-based fuel for another, taking corn out of the mouths of babes? Says Wass, “The beauty of these catalysts is that they can use all sources of ethanol biologically derived from any crop.” Corn stalks, wood, leaves, and switch grass are all being studied as sources of non-food biofuel.