What is in this article?:
- Scientists searching for biofuels best suited for Southeast growers
- The sugarcane connection
- Sweet sorghum
• Government mandates call for producing up to 36 billion gallons of biofuel to help meet the nation's transportation needs by 2022.
• While 15 billion gallons of that is expected to come from grain ethanol, the remaining 21 billion gallons will be derived from other feedstocks, such as sugarcane; perennial grasses, like switchgrass; and oilseed crops, such as rapeseed, pennycress, camelina, and soybeans.
The sugarcane connection
At the ARS Sugarcane Research Unit in Houma, La., and its field location in Canal Point, Fla., scientists are engaged in a program to supply growers and energy companies in the Gulf Coast and other southern states with new varieties of energy cane.
Energy canes are derived by crossing cultivated sugarcane with related wild grassy species that offer desirable traits for biofuel production.
A key attribute from wild grasses is their high amount of stalk fiber, which has cellulose and other complex carbohydrates that can be converted into ethanol, complementing the ethanol that would be produced from the sugar.
Another desirable trait from wild grass species is cold tolerance, important to both energy cane and traditional forms of sugarcane. Incorporating this trait would not only extend the growing and milling season, but also enable production in states where sugarcane is not traditionally grown, such as Arkansas, Mississippi, Georgia, and the Carolinas. (Commercial sugar production on the U.S. mainland is currently limited to Louisiana, southern Florida, and Texas.)
"We don't anticipate any energy cane being grown in the traditional sugarcane growing areas of Florida, Louisiana, Texas, or Hawaii," says Ed Richard, who, prior to retiring in December 2011, led a 12-member energy cane research team at Houma.
"We envision it being grown in the more northern zones of these states and in the other southern states, in rotations with pasture and other croplands that are not productive. In Hawaii, it may be grown on hilly land that is hard to irrigate," he says.
In Gulf Coast states like Louisiana and Florida, sugarcane is better suited to the region's soil types and subtropical climate.
"A long growing season, abundance of land, and the availability of water make the Southeast ideal for the production of tall-growing herbaceous perennials," like sugarcane, sweet sorghum, and other related species, says Richard. To date, the Houma group has released four energy cane varieties as part of a longstanding cooperative agreement with the Louisiana State University AgCenter and the American Sugar Cane League.