Sugarcane is better than soybeans for producing biofuel, study finds

U.S. researchers engineered sugarcane plants to convert sugars into lipids, or oils, which could be used to produce biodiesel. They believe it would be more economical to produce biodiesel from sugarcane, rather than soybeans.

A research team led by University of Illinois scientists engineered the plants to produce 12 percent oil by weight. With further development work, they expect to reach 20 percent in the future. This could provide 17 barrels of oil per acre.

By comparison, soybeans only provide about one barrel of oil per acre. At this rate the crop could never produce enough oil to meet demand, the University of Illinois said.

The study, published in the journal Biofuels, Bioproducts & Biorefining, says that biodiesel from “oil cane” could reduce the cost of biodiesel production from $4.10 to $2.20 per gallon.

Oil cane also has further advantages that have been engineered by the team. These include increased cold tolerance and more efficient photosynthesis, which leads to greater biomass production and even more oil.

“If all of the energy that goes into producing sugar instead goes into oil, then you could get 17 to 20 barrels of oil per acre,” said Stephen P. Long, University of Illinois crop scientist and lead investigator on the project. “A crop like this could be producing biodiesel at a very competitive price, and could represent a perpetual source of oil and a very significant offset to greenhouse gas emissions, as well.”

Another advantage of oil cane is that leftover sugars in the plant can be converted to ethanol, providing two fuel sources in one.

The team’s analysis showed that oil cane with 20 percent oil in the stem, grown on under-utilized acres in the southeastern United States, could replace more than two-thirds of the country’s use of diesel and jet fuel. This represents a much greater proportion than could be supplied by soybeans, even if the entire crop went to biodiesel production.

What’s more, oil cane could achieve this level of productivity on a fraction of the land area that would be needed for crops like soybean and canola, and it could do so on land considered unusable for food crop production, the researchers said.

Although $2.20 per gallon does not represent a significant saving over the current price of gasoline in the United States, Long argued that consumers and politicians should look at the bigger picture.

“We need to start building for a future when gas is no longer as low as $1.50 per gallon, and we need to avoid any future dependency on other countries for our oil,” he said. “We are lucky to have the land resources to do this and, in doing so, to ensure that future generations have a supply of oil that is domestic and renewable.”