Researchers evaluate sweet sorghum-to-ethanol potential in Maryland

By Lisa Gibson
Posted September 16, 2009, at 4:30 p.m. CST

A study to determine whether sweet sorghum is a viable crop on the Delmarva Peninsula in Maryland is in its first year and might lead to the construction of an ethanol plant on the peninsula.

Researchers from Salisbury University's Richard A. Henson School of Science and Technology collaborated with researchers from the University of Delaware, the University of Maryland at College Park, local farmers and the Lower Eastern Shore Research & Education Center for the three-year study. They established a one-acre plot of eight different types of sorghum on the Wicomico County farm, according to Christopher Briand, associate professor of biological sciences at Salisbury University.

Jeff Brenner of Solar Fruits Biofuels LLC initiated the study to determine if an ethanol plant on the peninsula could be sustainable, Briand said. The Maryland Grain Producers Association provided the funding for the first year and collaborators are looking for funding sources to continue in the second and third years, he said.

Meanwhile, the researchers are harvesting the crop, planted in May. "When we harvest each variety, we're harvesting approximately three-meter lengths," Briand said. One trial is irrigated and the other is not, he added. During harvesting, the stalks are counted and the biomass is weighed; the heads are removed; the seeds are collected and weighed; the juice is extracted and measured by volume and weight; and the sugar content is evaluated, Briand said. "What we're really looking for are varieties that grow well in the local conditions and produce lots of juice, i.e. have high sugar content," Briand said.

"We also look at the field," said Samuel Geleta, also an associate professor of biological sciences at SU. How the crops behave in the field is important in evaluating their potential, he said, such as whether they stand erect allowing for easy harvesting by machinery.

Sweet sorghum was chosen because alternative crops for ethanol production aren't as favorable for the region. Sugarcane doesn't grow well so far north, Geleta said, and corn competes with food crops and poultry feed. "Sweet sorghum is generally not used for that and we can grow it with less water and on marginal land so it will not compete with corn production," he said. In addition, corn-to-ethanol conversion is a lengthy process. Sweet sorghum juice, once extracted, can be fermented directly into ethanol, he said. "It kind of simplifies the process." Other states have experimented with sweet sorghum, along with India and China, but it is not commonly grown in the Delmarva Peninsula region, Geleta added.