A renowned bioenergy pioneer said Tuesday that production of corn-based ethanol doesn't result in as much net energy as production of other biofuels.
Jay Keasling, CEO of the Joint BioEnergy Institute in Emeryville, Calif., spoke as part of the Heuermann Lecture series at the University of Nebraska-Lincoln.
"You get just barely more energy out of the ethanol than you put into making it," said Keasling, who grew up on his family's corn and soybean farm outside of the small Nebraska town of Harvard. "That's a problem right now, a problem we need to fix."
Nearly half of the energy used to produce corn goes to making nitrogen-based fertilizer. Energy also is used to haul the corn to biorefineries, turn it into ethanol and then distill the ethanol. And, Keasling said, using corn as a biofuel competes with using it as food.
He described several other plants that can be used as biofuel that produce far more net energy than corn, including sugarcane-based biofuel, which produces about eight times as much energy as it takes to turn it into a biofuel. Switchgrass-based biofuel produces four times as much energy as it takes to turn it into a biofuel, he said.
"We're going to need other alternatives to corn if we want to be able to produce a lot of our energy, and these have to be non-food crops."
In 2007, Congress passed the Energy Independence and Security Act, which called for production of 36 billion gallons of renewable fuel by 2022 to reduce America's dependence on foreign oil. But achieving that goal will require dedication of about 25 percent of cropland to production of corn for use as a biofuel, Keasling said.
He said his institute has worked to improve the energy-producing potential of plants for use as biofuels through genetic engineering and other methods. One method involves removing from plants a chemical called lignin, that exists in plants' cell walls and serves to prevent extraction of sugar, the primary substance needed to produce ethanol.
Keasling and his colleagues have engineered a strain of E. coli bacteria to produce biodiesel fuel from biomass such as switchgrass without the need of enzyme additives. Now he is seeking ways to make that discovery economically competitive in the quantities needed.
He said it likely will take decades and consistent government policies for biofuel production to become established firmly in America. He said the market, not the government, should decide which crops should be used to produce biofuel.
"I think we have a bright future," he said. "We're going to need a lot of research in this area, but I think it could be great for Nebraska."