According to industry estimates, producing more than 30 Ggal of ethanol from U.S. corn would seriously disrupt feed and food markets. With that in mind, alternative feedstocks are being considered for increasing ethanol production. Based on pilot operations in Canada and the U.S., the office of the U.S. Energy Secretary predicts that converting crop waste and prairie grasses into ethanol could be economically and financially feasible within five years.
Government and private sector scientists have been working for years on ways of reducing the cost of producing ethanol from cellulosic material. Researchers at the University of Nebraska-Lincoln pegged the cost of cellulosic ethanol in 1982 at US$3.60/gal. The ultimate goal is to bring down the cost of cellulose ethanol to the same level as corn ethanol, or about US$1.10/gal, but US$1.50/gal appears to be a more realistic goal in the medium-term. A limiting factor for the production of cellulosic ethanol is the amount of feedstock, within a 60 mile radius, needed to maintain an efficiently sized plant producing 100 Mgal of ethanol annually.
Ethanol produced from switchgrass, mixed prairie grasses and woody plants grown on marginal land could potentially meet the growing demand for fuel. There may even be some added economic benefits from developing the cellulosic ethanol market, in particular, increasing employment for rural communities.
There is currently no commercial production of ethanol from cellulose, although the first commercial plant is being planned in Spain. A U.S. firm recently announced plans to convert their conventional dry milling facility in Emmetsburg, Iowa to the production of ethanol from cellulosic material. This would be the first commercial-sized cellulosic ethanol plant in the U.S. and it would use the stalks, leaves and cobs from corn, as well as grain corn, to produce ethanol. Once fully operational, the Emmetsburg plant would produce about 125 MGal of ethanol annually.