Carbon Farms

Ever heard of miscanthus x giganteus?

I hadn’t either, until I read this articlein the San Francisco Chronicle. A bunch of alternative-energy researchers are betting that this Asian superweed will be the next big thing in biofuels.

Turns out that miscanthus is an incredible sources of cellulose, a form of carbon found in organic materials that can be converted into fuel. The tropical reeds can grow as tall as 12 feet, live for two decades or more, require little water or fertilizer, and are easy for farmers to cultivate. All of that makes it almost ideal as a potential biofuel crop.

For years, ethanol was such niche product that nobody really paid much attention to the economics of producing millions of gallons of the stuff. Indeed, the U.S. produces so much corn and soy, the two main sources of ethanol, that turning it into fuel was seen not as an energy strategy but a way of disposing of excess crops.

But now that biofuels are getting so much attention, people are starting to put some thought into what it will take to convert potentially millions of acres of farmland into, as the Chronicle put it, “carbon farms.” Think about it for a second. The U.S. has about 425 million acres of arable land, but if we start converting huge swathes of farmland to growing miscanthus, that means less produce for your table, which could drive up the price of food, which is probably one of the few things that would be even more unpopular than spiking gasoline prices.

That’s why it makes sense to start looking for the plants that will produce the best juice, that is, the ones the produce the most organic material per acre, with the least impact on the environment, and that can be refined into the most powerful form of fuel. Remember, we didn’t start making ethanol out of soy and corn because some scientist determined that they make the best gas – we just had too much of the stuff laying around. Maybe cellulose will turn out to be a more efficient source of power than the sugars in corn that are used to produce ethanol.

In fact, you can make biofuel out of almost anything. I wrote a story last year for Wiredabout a guy who had some fat liposuctioned out of his butt and converted into biodiesel, but animal fats, algae, even used restaurant grease, will all do, as long as it will explode inside the cylinder of an engine. That reaction converts the stored energy in a fuel into the mechanical energy needed to move a piston. Petroleum happens to be an efficient way to store this energy, and, until the latter part of the last century, we thought we had plenty of that laying around too.