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June 05, 2009
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I heard about a new molecule called 'Q' that can turn almost anything into ethanol: paper, plywood, etc. What can you tell me about Q?
— Kate
Boston, Massachusetts
 Yes, "Q" does seem to exist. And it could potentially destroy my dream to see the world run out of oil and descend into Mad Max-like chaos (where I would rule the roads in my French fry car). Its creators say it can supposedly turn almost any plant waste material (like corn stalks, sawdust, grass clippings) into fuel. If they're right, it might be the silver bullet for cars.
To explain fully, I need to give some background. Ethanol is another name for ethyl alcohol—or, the same stuff in our wine, beer, and margaritas that gets us tipsy. People have been making it for thousands of years by taking the simple carbohydrates in wheat, corn, potatoes, rice and other starchy crops, converting them to sugar, and then fermenting those sugars by adding yeast. (Grapes and other fruits are already basically sugar, so you can skip the conversion process and go straight to the fermenting.) The yeast can't reproduce when the alcohol content reaches 15 percent, so the fermentation process stops at this point (and this is why wine and beer generally can't be any stronger than 15 percent alcohol). To create harder booze, you separate the alcohol from the water by slowly boiling it and capturing the alcohol vapor (which turns to steam at a lower temperature) in a separate container. This process is called distillation. Bottoms up!
With simple modifications, modern internal combustion engines can run pretty well on ethyl alcohol (or ethanol), because it's such an explosive substance. There are some problems, though. The first is that creating it is energy intensive. Most ethanol plants in the US use natural gas to generate the massive amount of heat needed for distillation. Then there's the issue of using corn as a fuel source. It creates a battle for food crops between energy producers and people who want to put a meal on their plates—so prices go up. When corn demand rises, farmers begin to plant more of it at the sake of wheat and soybeans—which in turn become more expensive and scarce. This is why corn-based ethanol is such a disaster.
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This microbe Q could potentially be a simple and elegant way to solve these problems. It can break down even the complex carbohydrates (also known as cellulose) of just about any plant's body (a blade of grass, a grapevine, a tree trunk), ferment it and turn it into 80 percent ethanol. Q could eliminate the use of food crops for fuel, and allow us to take advantage of native perennial plants that need almost no water or fertilization and grow on traditionally non-agricultural lands. (Think "switchgrass.") If it works, that is.
Q is a natural microbe, discovered in the western Massachusetts soil by Susan Leschine, a biology professor at UMass. A company called Qteros plans to begin small-scale cellulosic ethanol production using the Q technology later this year. Personally, I'll remain skeptical about its use until people actually start pumping Q-made ethanol into their gas tanks. Or maybe I'm just in denial, holding onto the glimmering hope that I can still become a grease-powered ruler in a dismal Mad Max world.
Eco Adventurer
Greg Melville is the author of Greasy Rider, a new book in which he drives across the country in a fry-oil-powered car investigating the future of green technology. A journalist who has written for Outside, The New York Times, and Popular Mechanics, Melville blogs about all things eco at greasyriderbook.blogspot.com. He lives with his wife, kids, and dog in Asheville North Carolina.
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