Researchers from University of Illinois conducted a study and found that grass that grows all year round will yield more ethanol output and lesser greenhouse gases emissions.

The least productive farmlands in many parts of the United States are planted with corn used for ethanol production. Grasses like miscanthus, a hybrid grass used in Western Europe and switchgrass, which is native in the United States.

The researchers used a computer model of plant growth and soil chemistry to compare the ecological effects of growing corn and the grasses. Based on the analysis, the switch can yield to a variety of ecological advantages.

Evan DeLucia, a professor in University of Illinois and the lead researcher of the study, said that based on the computer model, the replacement will convert the whole area from a source of greenhouse gases in the atmosphere to a sink.

Using grass as biofuel feedstock will decrease levels of carbon dioxide and nitrous oxide emitted by corn.

Moreover, miscanthus and switchgrass are both perennial grasses, which mean that they will cause fewer disturbances to the soil as compared to corn tilling every year.

According to the researchers, "If cellulosic feedstocks (such as miscanthus) were planted on cropland that is currently used for ethanol production in the U.S., we could achieve more ethanol (plus 82 percent) and grain for food (plus 4 percent), while reducing nitrogen leaching (minus 15 to 22 percent) and greenhouse gas emissions (minus 29 percent to 473 percent)."

The researchers said the agricultural sector contributes about 14 percent of the overall greenhouse gases that cause global warming.

The researchers said that miscanthus grows on marginal land without the need of fertilizers, so using it as a biofuel feedstock instead of corn would eliminate a major source of air and water pollution. Nitrous oxide is a byproduct of the fertilizers used on cornfields.

Based on a separate study, switch grass can produce more than enough cellulosic ethanol on a per-acre basis to offset the amount of energy needed to grow and convert the perennial prairie grass into biofuel.

The only problem faced by the switch is the conversion of grass into fuel. The conversion of sugars in corn is much easier than deriving the sugar locked on the leaves and stems of the grass.

However, there is one commercial-scale lignocellulose biorefinery that is under construction in Florida that addressed this problem. (K.A.D. Mariano)

source: apec-vc korea