In an effort to reduce our dependency on foreign oil, the U.S. has been working to ramp up its plant-based ethanol production in recent years, and while we’re falling short of Congress’s 500 million gallon goal for 2012, things are on the up and up. Just this week, the Department of Energy announced a $105 million loan guarantee to build a plant in Iowa that will produce up to 25 million gallons of cellulosic ethanol each year. The plant, being constructed by POET, will be the first commercial-scale of its type, and would work with local farmers to process more than 700 million tons of non-food corn waste into fuel.
“This project will help decrease our dependence on oil, create jobs and aid our transition to clean, renewable energy that is produced here at home,” said U.S. Energy Secretary Steven Chu. The loan from the government is the first by the Energy Department for the production of cellulosic ethanol.
Most of the United States’ ethanol is made from corn, which many critics say is a waste of valuable food. But the new plant would use only the non-food parts of corn: the cobs, the husks, and the leaves. POET is already a major producer of ethanol made from corn kernels (they have 27 plants in operation), and since 2008, they have run a pilot plant using the other parts of corn. But the pilot plant only converts one ton of biomass a day, so POET has some technical issues to solve in terms of scaling up their production to be able to handle the expected 700 million tons. The new plant is expected to produce enough fuel to power itself and supply some energy to the corn ethanol plant next door.
The president of POET told the New York Times that the cost of their cellulosic ethanol is about $0.50 more than POET’s ethanol made from corn kernels. He also says that the company’s main goal is to make the product competitive with corn ethanol and gasoline. To transform corn waste, which is known as stover, into fuel, the cobs, husks, and leaves are steamed and treated with acid. Then enzymes are used to break down the stover into two types of sugar, which are then converted by yeast into alcohol
If the production of ethanol from corn waste can become economical, it would be a huge boost for the United States in a number of ways. It would reduce the amount of edible corn used to make fuel, and it would vastly increase the country’s potential to make motor biofuels, thus decreasing our use of fossil fuels. If POET finds success using corn waste in the new plant, the Energy Department hopes that it will spur other plants and ethanol producers to do the same.