As concern about global warming and dependence on fossil fuels grows, the search for renewable energy sources that reduce CO2 emissions becomes a matter of widespread attention. Production of ethanol (bioethanol) from biomass is one way to reduce both the consumption of crude oil and environmental pollution. Using bioethanol-blended fuel for automobiles can significantly reduce petroleum use and exhaust greenhouse gas emission. While more expensive to produce than other fuel types, bioethanol production boosts the farm economy. Up to 80% of production cost is the cost of feedstock. Bioethanol can be produced from cellulose feedstocks such as corn stalks, rice straw, sugar cane bagasse, pulpwood, switchgrass, and municipal solid waste.