bioethanol

Bioethanol is a renewable alcohol fuel produced primarily by fermenting sugars or starches from plant biomass. It is used mainly as a transportation fuel or fuel additive, blended with gasoline in ratios such as E10, E15, or up to E85 in flexible-fuel vehicles.

Most bioethanol is produced by fermenting simple sugars to ethanol, followed by distillation and dehydration to a fuel-grade product. For starch-rich crops, enzymes convert starches to sugars before fermentation. Cellulosic or lignocellulosic feedstocks (grasses, wood residues, agricultural wastes) require pretreatment to release sugars and later enzymatic hydrolysis; commercial-scale production in this segment has faced technical and cost challenges.

Common feedstocks include sugarcane and corn, as well as wheat, barley, beet, and various crop residues. The use of non-food or waste biomass can reduce food-fuel competition, but land, water, and fertilizer use remain concerns. Lifecycle greenhouse gas emissions vary widely and depend on feedstock, farming practices, and energy sources used in processing.

Policy and market factors influence bioethanol development. Incentives, mandates, and sustainability criteria aim to ensure a net reduction in emissions and avoid adverse effects on food supply. Global production is concentrated in Brazil and the United States, with growing interest in domestic and regional bioethanol in other regions.

Safety and handling: ethanol is highly flammable and requires proper storage and ventilation. While bioethanol can reduce reliance on fossil fuels, its overall environmental and economic benefits depend on the feedstock, production methods, and supply chain management.