A hybrid grass that can grow up to 13 feet high has potential to become an important renewable energy source, according to research conducted at the University of Illinois at Urbana-Champaign (UIUC). Professor Stephen P. Long contends that the grass, Giant Miscanthus, is a source of solid fuel that could join ethanol and biodiesel as a biofuel option.
Miscanthus, also known as elephant grass or E-grass, is a perennial grass native to Asia. Related to sugarcane, it grows from an underground stem-like organ called a rhizome. When the grass drops its leaves in winter, tall bamboo-like stems remain; these are harvested and are the source for a clean-burning fuel. Full-grown plants may produce 10-30 tons/acre dry weight each year.
Long, a UIUC professor of crop sciences and plant biology, has been studying Miscanthus with the help of his two doctoral students. Using computer simulation, they have predicted that if just 10 percent of the land in Illinois was used to grow the grass, 50 percent of the state’s electricity needs could be supplied by the biofuel it produced.
According to the UIUC research, the U.S. Department of Energy has been investigating and breeding another plant, switchgrass, since the mid-1980s. Although this plant can also produce a clean-burning and high-energy fuel, it has proven to be unprofitable. Meanwhile, scientists in Europe have been studying Miscanthus, and for many years now it has been grown commercially, particularly in areas near the Alps, where the climate is similar to that of the midwestern United States.
In 2002, the University of Illinois conducted a side-by-side trial of Miscanthus and switchgrass. Once the crops reached full-stand maturity in 2005, the results showed Miscanthus yielding 25 tons/acre, whereas switchgrass produced only 11 tons/acre. Since the grass was first introduced in the United States, varieties of it have been grown in Indiana, Michigan, and Ohio.
The UIUC study shows that Miscanthus has many benefits. It is easy to grow because it requires little water, minimal fertilizer, and thrives in untilled fields. When burned it produces only as much carbon dioxide as it removed from the air as it grew, meaning that it is a carbon-neutral fuel. Also, studies show that Miscanthus is an energy-efficient fuel because the energy it provides is more than the energy needed to produce it.
Long said he next plans to collaborate with the Institute of Genomic Biology to determine if Miscanthus can be converted into another fuel source in the form of alcohol.