MICHELE NORRIS, host:
Two years ago, most Americans got an introduction to a term they'd never heard of.
(Soundbite of 2006 State of the Union Address)
President GEORGE W. BUSH: Switchgrass.
NORRIS: That's President Bush during his 2006 State of the Union address. He presented a laundry list of things his administration would do to help America kick its oil habit.
Pres. BUSH: We'll also fund additional research and cutting-edge methods of producing ethanol, not just from corn, but from wood chips and stalks, or switchgrass.
NORRIS: Since then, a lot of switchgrass has been through the mill, so to speak. But there's been little evidence that growing grass could actually make a dent in our demand for oil. Now, there's new research showing that this prairie plant could be a good source of ethanol.
Here's NPR's Christopher Joyce.
CHRISTOPHER JOYCE: Right now, Americans get their ethanol fuel from corn, so much of it that corn prices have been bouncing up near their historical ceiling. A lot of economists say if the country wants more ethanol, it should not come from food. Thus, switchgrass. It's a kind of prairie grass, but you don't have to go to the prairie to find it. For example, it grows on the banks of the Chesapeake Bay in Maryland, where Ken Staver has been tending a plot for years. It's six-feet high, yellowish, and stiff as a pencil.
Mr. KEN STAVER (Scientist, University of Maryland): As you can see, it's doing, done very well here with very little care other than when we planted it 10 years ago, we used some herbicide during the establishment phase. But since then, there's, literally, the only thing we do out here every year is harvest it.
JOYCE: Switchgrass contains cellulose, the starting material that, with enough heat and the right enzymes and chemicals, can be made into ethanol fuel. Staver, a scientist with the University of Maryland, says one of the good things about this grass is that it pretty much grows by itself.
Mr. STAVER: It's considered a perennial plant. So, it does reseed some, but mostly these are the original plants. It's not growing back from seedlings every year, it's growing back from the same, from the same rootstock.
JOYCE: So you don't have to plant it every year or even fertilize it much, and it's easy to harvest. And these things are essential if you want to make fuel from plants, biofuels. The more energy you use to make them, say, gas for tractors or electricity to convert them into liquid fuel, the lower your net energy yield. In short, if it takes close to a gallon of gasoline to make a gallon of biofuel, why bother?
Well, plant scientist Ken Vogel, at the federal government's Agricultural Research Service in Nebraska, has done a new study that says switchgrass is worth the bother. Vogel spent five years with farmers growing switchgrass in the Midwest. It was one of the biggest experiments with actual crops. He calculated with what might seem like mind-numbing thoroughness, everything that went into each plot.
Mr. KEN VOGEL (Scientist, United States Department of Agriculture-Agricultural Research Service): And this includes the energy used for fuel, the energy used to make the tractors, the energy used to produce the seed to plant the field, the energy used to produce the herbicide, the energy used to produce the fertilizer, the energy used in the harvesting process.
JOYCE: Vogel says for every unit of energy used to grow the switchgrass, he could get almost five and a half units worth of ethanol out. And that's a lot more efficient than making ethanol from corn, he says.
Mr. VOGEL: The bottom line is perennial energy crops are very net energy-efficient. It is going to be economically feasible, the basic conversion technology has been developed, and it is going to be a viable process.
JOYCE: Now, Vogel has focused on the growing part of the process, mostly. He hasn't demonstrated that commercial distilleries can actually achieve the same level of efficiency.
One issue is how you power your distillery. If you use electricity made from coal, you lose some of the advantage of biofuels. Vogel argues that a distillery could regain that advantage by burning leftover parts of the switchgrass to generate the energy.
Vogel's research appears in the latest issue of the journal Proceedings of the National Academy of Sciences.
Christopher Joyce, NPR News.
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