The Biofuel Center of North Carolina celebrated its fifth birthday earlier this year. Since it’s inception, a great number of plant materials have been grown and tested for their suitability as a biofuel stock, ability to transport nitrogen out of the soil, and offer enough return on investment to make them profitable for the grower. Sam Brake, Director of Farming with Biofuels Center says they’ve a few that were a swing and a miss:
“Industrial sweet potatoes which was our big starch sweet potato that theoretically could be converted to starch to sugar to ethanol. We looked at sugar beets that are not exactly free sugar but very close to it, one of the crops that table top sugar is processed from, and tried to easily convert that sugar into ethanol. Those two crops are grown on good agricultural land that already has a use.”
So, now most of the Biofuel Center’s research focuses on grasses, or dual use crops:
“The things that get most of our interest now are grasses, some interest in annual grasses like grain sorghum because the grain can be used to feed animals and the stover that is left can be used to provide feed stock for cellulosic ethanol.”
Certain types of grain sorghum are just such a dual use crop according to Brake:
“If a farmer is going to grow grain sorghum, then he might want to grow a dual purpose sorghum that grows a little taller that makes the same amount of grain but gives twice as much bio mass. Then we look at our bio mass sorghums that will grow 10-12 tons per acre. But its an annual crop so it has the annual expense of planting and managing weeds.”
And then there’s the perennial type grasses:
“That leads us to some perennial crops such as switch grass, miscanthus and arundo donax. They are the crops on our radar now. The advantage of the perennials is once you get them established you don’t have to do that again at cost every year. Once they get well established in their third year, they can out compete weeds. The disadvantage is they are more expensive to establish.”
The Biofuels Center along with NC State is currently researching Arundo Donax, a controversial potential biomass material that has neither approval from the EPA as a third generation biomass or from the states of North and South Carolina for mass production. Arundo has a reputation for getting out of control, much like kudzu, especially around water.
Director of Farming with Biofuels Center, Sam Brake on Inside Agriculture.
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