How does Iogen make cellulosic ethanol?
The wheat, oat, and barley straw is first pretreated. Iogen’s patented enzyme — an active protein made from a fungus — breaks the cellulose down into sugars, which are then fermented and purified into ethanol. The enzymes are nontoxic and biodegradable. One of the big side benefits is that the plants used to create cellulosic ethanol contain lignin, a compound that is separated out in the process and can then be burned to create energy. Iogen uses the lignin in a combined heat and power plant that generates the energy needed to run the demonstration facility. Does it cost more than regular gasoline or regular ethanol? At the moment, yes, but it’s an unfair comparison because cellulosic ethanol hasn’t yet been manufactured on an industrial scale. Tax subsidies to the oil industry distort the true cost of gasoline, but when those distortions are removed, cellulosic ethanol is one of the lowest-cost ways to reduce gasoline usage and is cost-competitive with regular ethanol.
