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Surely Some Flora Out There Can Fuel My Car

While the corn ethanol bubble has pretty much popped, serious efforts to find an economically sound and carbon-smart biological-based fuel continue.

William Frey holds up a beaker of brown slush, plucked from the clutch of an automated carousel swirling dozens of glass containers. The liquid, a mix of ground corn stocks and a microscopic organism named the Q-Microbe, may just be the fuel of the future, Frey says.

"We're on the right path. This works," says Frey, president of Qteros, a company outside Boston that is reaping ethanol in their labs from colonies of a single-celled bacteria found in the dirt beside a Massachusetts reservoir. "If money were no problem, we could build plants today."

Qteros is part of a rush to develop what one expert calls "the holy grail" of energy, a biological-based fuel that can replace petroleum. The potential reward is huge: saving the world from catastrophic climate change, powering our society with abundant new energy, and ending a global economic imbalance now tilted toward nations that happen to sit atop oil reserves.

President Obama is betting that reward can be had. He has announced an effort to promote biofuels, pledging $786.5 million dollars of stimulus money to research and development. Biofuels will be "an integral part of this new 21st-century American economy," proclaimed Obama's agriculture secretary, Tom Vilsack, in presenting the plan May 5.

The good news is that science has the answers; researchers at Qteros and dozens of other labs have succeeded in a variety of ways to make fuel from plants and organisms. The bad news is that all face daunting challenges to producing fuel in the volume we need at a price we can afford. And, as with corn ethanol, there are certain to be unforeseen consequences of ramping up to a large scale.

Corn-based ethanol succeeded quickly on an industrial scale because most of the elements were in place: vast cornfields, an infrastructure for moving corn to processors, and an age-old fermentation science used by moonshiners. The new generations of biofuels do not have all those advantages.

The search for new strategies generally falls in two camps: ways to use organic stuff other than corn to make ethanol, and ways to manipulate organisms to produce a different fuel identical to gasoline or diesel.

The search for a better ethanol — "cellulosic ethanol" — is farthest along, hitching on the experience of corn ethanol. Almost any organic matter — from the leftover corn stalks after harvest to garbage to grass to sawdust — has cellulose that can be fermented into ethanol. Researchers are exploring ways to use acid or enzymes to break the cellulose away from the lignin that gives the plant its structure. Cows and sheep do this in their stomachs naturally.

Its promoters say corn-based ethanol is only the flawed first version, and that cellulosic ethanol will end the competition of food with fuel, and spread the organic sources of ethanol over a much larger and diverse landscape.

They envision vast fields of switchgrass, a tall prairie grass, grown without water on vacant land, and harvested for fuel. They note that the lignin plant structure that is left after cellulose and carbohydrates are taken can be burned to help fuel the conversion process, giving the whole operation a much better greenhouse gas advantage than simply fermenting corn.

Congress has written this idea into the law with the same vigor that it embraced corn ethanol. In the 2007 Energy Independence and Security Act, Congress said that of the 36 billion gallons of biofuel it wants produced by 2022, 15 billion gallons must come from corn-based ethanol and at least 16 billion gallons from cellulosic biofuels.

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