Making ethanol even greener
For some time, a cloud has dimmed the greenness farmers see in ethanol. It’s a fog spewed by Washington interest groups. It leads some to believe that higher corn prices loosely tied to ethanol also have this environmental side effect: Farmers in poorer countries slashing rain forests and plowing tropical savannas to plant corn and beans. That, activists argue, puts more carbon into the air than ethanol saves.
The fog is starting to lift.
The EPA still uses this theory, called indirect land-use change (ILUC), but has lowered earlier estimates of its effects. So ethanol and biodiesel qualify for mandates to be blended with gasoline and diesel. And a look at ILUC by Purdue University found ethanol’s carbon footprint 10% to 20% smaller than gasoline’s.
So far, California still sees ethanol as not so green. To start enforcing its own climate law, the California Air Resources Board (CARB) created carbon intensity values for gasoline, ethanol, and other fuels. CARB gives each fuel a score, based on how much CO2 equivalent it puts out in a unit of energy. Gasoline’s carbon intensity value is 95.86. The average for Midwest corn ethanol would be 69.4 without ILUC. But CARB adds another 30 points for land use, giving ethanol a score of 99.4. So gasoline comes out looking greener than most ethanol.
This means Midwest corn ethanol may become hard to sell in California. Ethanol groups have sued CARB, challenging the constitutionality of its Low Carbon Fuel Standard.
Meanwhile, an ethanol plant in Winnebago, Minnesota, is poised to beat CARB at its own game. Corn Plus, a farmer-owned 49-million-gallon plant built in 1993, has become one of the nation’s most energy-efficient fuel producers – and it’s aiming to prove that to CARB.
In 2005, Corn Plus put in a fluidized bed reactor to burn syrup from distillers’ grains for energy. It saved almost $30 million in natural gas, well over the reactor’s $20-million price if bought today, says Keith Kor, who recently retired as Corn Plus manager.
Corn Plus gets a third of its electricity from two on-site windmills financed by John Deere. “That was not so much cost savings, but it seemed like the right thing to do,” says Bill Drager, a farmer who is the Corn Plus board president.
Like other plants, Corn Plus has had run-ins with EPA and state regulators. In 2002, they said Corn Plus was polluting the air with volatile organic compounds. Most plants added thermal oxidizers to destroy them, says Larry Becker, environmental health and safety manager for Corn Plus. His plant chose the fluidized bed to do that and to save fuel as well.