Ethanol for $1 a Gallon, without Corn

Coskata, which is backed by General Motors and other investors, uses bacteria to convert almost any organic material, from corn husks (but not the corn itself) to municipal trash, into ethanol. "It's not five years away, it's not 10 years away. It's affordable, and it's now," said Wes Bolsen, the company's vice president of business development.

Coskata uses existing gasification technology to convert almost any organic material into synthesis gas, which is a mix of carbon monoxide and hydrogen. Rather than fermenting that gas or using thermo-chemical catalysts to produce ethanol, Coskata pumps it into a reactor containing bacteria that consume the gas and excrete ethanol. Richard Tobey, Coskata's vice president of engineering, says the process yields 99.7 percent pure ethanol.

May Wu, an environmental scientist at Argonne National Laboratory, says Coskata's ethanol produces 84 percent less greenhouse gas than fossil fuel even after accounting for the energy needed to produce and transport the feedstock. It also generates 7.7 times more energy than is required to produce it. Corn ethanol typically generates 1.3 times more energy than is used producing it.

Ethanol for $1 a Gallon without Corn