Trash Crops to Cash Crops
Two guys in a pickup truck brewing fuel from farmed trees and grasses aim to show Americans that switching to alternative fuels is a viable option right now.
When cattle and hay farmer Wayne Keith took a road trip from his spread in Springville, Ala., to Northern California, his first stop wasn't a gas station; it was a Dumpster behind a furniture factory. He emptied the half-ton of wood scrap into an open trailer, fed some into a boiler-like device mounted on the trailer hitched to his 1991 Dodge Dakota and took off on the 7,000-mile round-trip journey, stopping every 90 miles or so to pop some more wood into the burner.
"That's a cheap ride, on somebody's garbage," he said.
Back in the 1970s, when the OPEC oil embargo squeezed oil supplies and increased the price of gas by 70 percent, Keith, a handy guy who likes to tinker and also creates sculptures out of junk lying around the farm, searched for a petroleum alternative. He learned about gasification, a method of slowly burning organic material and capturing the gasses to power an engine that had been used in World War I. Then, gas prices went down and he forgot about it for 30 years.
Five years ago, as gasoline neared $2 a gallon, Keith began experimenting with gasification, finally converting three farm trucks. The gasifiers on his pickups take the place of the carburetor, delivering combustible fumes to the pistons. A gasifier can use wood, dry brush, paper, corn stalks – almost anything that's dry enough to burn. Keith gets about 2 miles out of 1 pound of dry wood.
His 200-acre farm in the foothills of northeast Alabama is energy self-sufficient. Windmills provide electricity, the sun heats his water and wood from his sawmill provides the fuel for all his vehicles. Keith may sound like a back-to-the-lander, but he's really at the forefront of a movement to turn the American South into a 21st-century OPEC.
Keith and his pal David Bransby, a professor of energy crops and bioenergy at Auburn University in Alabama, have spent the past few years barnstorming the country, trying to demonstrate how the South could become the linchpin of America's new energy policy.
"We're not suggesting everyone needs to run their car on wood," Bransby explained. "But we are suggesting that people can run their cars on fuel derived from wood."
Bransby's idea: Instead of siphoning away resources from food and feed production, why not make fuel from easily renewable and already available resources?
"Down here in the South, we have more wood than we know what to do with," Bransby said. "Right now we're accumulating wood in the Southeast because markets are evaporating." The pulp and paper industry has moved overseas, while the lumber industry is suffering along with the housing market.
Wood isn't the only potential oil-producing crop. Switchgrass, a tall, native grass that once covered the Central Plains, and which seems to thrive even in the depleted soils of Alabama cotton fields, is a promising biomass candidate. Bransby grows switchgrass in the agriculture school's test fields, searching for the most efficient methods to produce the greatest yield. Leftovers from farming — everything from corn and cotton stalks to poultry litter — could be refined into green gold.
On Keith's farm, scraps from his sawmill power his vehicle, along with hay that's gone bad. They used to call this stuff agriculture residue; now, it's known as biomass.
In Bransby's vision, farmers could grow biomass crops on land that's too poor for food crops, then haul them to local refineries. The ideal solution would be a network of smaller plants located near centers of biofuel production that could use one process to transmute a variety of substances into fuel. A thriving market for this biomass could support struggling Southern farmers without competing with other agriculture.
One gotcha of biofuel of any kind is that it can take almost as much fuel to grow and transform the crop as can be extracted from it. That's a huge problem with corn ethanol: For every unit of energy expended in growing, harvesting and conversion, 1.67 units come back. For switchgrass or wood, the energy balance is 4 to 1, said Bransby, who is on the boards of two bioenergy companies and the editorial board of the journal Biomass and Bioenergy. He says a U.S. harvest of 1.3 billion tons a year from forestry and agricultural byproducts could chip 15 percent annually off the nation's petroleum use.
In all these biofuel schemes, the devil is in the math.
Studies conflict about how much biomass would be available, how much it would cost to convert energy crops to fuel oil and how much of a dent production could make in the U.S. oil binge. An unbiased 2008 market analysis by the University of Georgia's Center for Agribusiness and Economic Development estimates that there may be more than 13 million tons of biomass in Georgia that could be converted to electricity each year. If the entire mass were used, the center estimates it would meet 8.6 percent of the state's annual electricity consumption. (See Table 3 on Page 13.)
Neither is this stuff free for the taking. In fact, Andy Aden, a senior research engineer at the National Renewable Energy Lab, notes that the "delivered cost" of biomass gets higher the more you use, because the material that's cheapest to harvest gets used first. He's seen estimates for delivering a ton of wood ranging from $30 to $60.
Calculations of the output of biofuel plants can be just as various.
George Shumaker, professor emeritus of agriculture and applied economics who heads CAED, says biofuel companies with terrific lab results have struggled when they tried to scale up to full production.
"The dirty little secret out there is that coal and petroleum are our most efficient forms of energy," he said. "These new technologies have to find a way to convert these biomass products that is economically competitive."
Aden says the sticking point right now is making the business case to farmers. A corn farmer may make $450 an acre; the additional $40 he might get for going over the field a second time to harvest the stalks doesn't seem worth it. When it comes to switchgrass, "There's not a lot of it grown right now. It's a chicken-and-egg thing — who do I sell the switchgrass to?"
Bransby acknowledges that.
"We do need some help from the feds to kick this industry off."
The Farm Bill of 2008 provides $118 million for biomass research and instituted the Biomass Crop Assistance Program. But rule-making to implement these programs is idling. Meanwhile, the American Recovery and Reinvestment Act of 2009 (aka the Stimulus Package), signed into law on Feb. 17, provided $16.8 billion to the Department of Energy's Office of Energy Efficiency and Renewable Energy. That includes $6 billion to help finance renewable energy and electric transmission technologies, $800 million for its biomass program, up to $1.6 billion to finance clean and renewable energy projects and a three-year extension of the investment tax credit for renewable energy production.
When the industry takes off, Bransby says, "This technology will beat petroleum down to $12 a barrel."
Meanwhile, Wayne Keith feeds junk mail, sawmill detritus and the occasional plastic jug into his gasifier and keeps on trucking.
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