Biofuel ethanol, often referred to simply as ethanol, is a type of renewable and alternative fuel made from organic materials, typically derived from crops like corn, sugarcane, and various biomass sources. It is used as a substitute for, or an additive to, gasoline in the transportation sector. Ethanol is considered a biofuel because it is produced from biomass, which can be grown and harvested repeatedly, making it a more sustainable and environmentally friendly energy source compared to fossil fuels.

Here are some key points about biofuel ethanol:

1. Production: Ethanol is produced through a fermentation process where sugars or starches from biomass sources are converted into alcohol. Common feedstocks for ethanol production include corn, sugarcane, wheat, and various cellulosic materials.
2. Types of Ethanol: There are two primary types of ethanol used for fuel:
   • E10: This is a blend of 10% ethanol and 90% gasoline, which is the most common ethanol blend used in standard gasoline vehicles.
   • E85: E85 contains 85% ethanol and 15% gasoline. It is primarily used in flexible fuel vehicles (FFVs) designed to run on this higher ethanol blend.
3. Environmental Benefits: Ethanol is considered a cleaner-burning fuel because it has a lower carbon content than gasoline. It reduces greenhouse gas emissions, air pollution, and dependence on fossil fuels. The carbon dioxide (CO2) released when burning ethanol is offset by the CO2 absorbed during the growth of the feedstock.
4. Renewable Resource: Ethanol production relies on renewable crops and biomass sources, making it a sustainable and renewable energy resource.
5. Energy Security: Biofuel ethanol reduces a country’s dependence on imported oil, enhancing energy security.
6. Economic Benefits: Ethanol production supports the agricultural sector and can provide economic opportunities in rural areas.
7. Challenges: There are concerns about the environmental impact of large-scale mono-crop farming for ethanol feedstock, potential impacts on food prices, and land-use changes. Additionally, the energy required for production, transportation, and processing can offset some of its environmental benefits.
8. Flex-Fuel Vehicles: Flex-fuel vehicles (FFVs) are designed to use various ethanol blends, including E85. These vehicles have special sensors and engine controls that can adapt to different ethanol-to-gasoline ratios.
9. Blender Pumps: Some gas stations offer blender pumps that allow consumers to choose their preferred ethanol blend, such as E10, E15, or E85, providing more flexibility for consumers.

Biofuel ethanol is a key component of efforts to reduce the environmental impact of the transportation sector and promote more sustainable and cleaner energy sources. Its use has grown in many countries, often in response to government policies and incentives designed to promote the use of biofuels.