Digestion of biomass material and its fermentation represents the best path forward for bio-ethanol production. While starch based feedstocks have been used extensively, it is believed that lignocellulosic energy sources offer a better long-term prospect as a source for fermentable sugars. Lignocellulosic feedstocks, such as wood chips, corn stover or switchgrasses do not directly compete with food sources for land or consumption. Regardless of the source of feed stock, current production costs make them unpalatable as a fuel. The International Energy Agency (IEA) has estimated that the cost of producing and retailing diesel and ethanol from cellulose to be $1.10 per liter of gasoline-equivalent, while ethanol from corn or sugar cane costs $0.62-0.75 compared to $0.54 for gasoline