E20 vs E85 vs E100: Key differences in ethanol blend, mileage & engine compatibility  - BusinessToday

The key difference between E20, E85 and E100 lies in the amount of ethanol mixed with petrol, and that directly affects where the fuel can be used, how vehicles perform and what kind of engines are required. E20 contains 20% ethanol and 80% petrol, making it the most widely adopted ethanol blend for everyday passenger vehicles. It has been introduced as a cleaner alternative to regular petrol without requiring a complete redesign of modern engines. Most new vehicles manufactured for the Indian market are now being made E20-compatible. E85 contains between 51% and 85% ethanol, with the exact composition varying depending on climate and seasonal requirements. Because ethanol behaves differently from petrol during combustion, E85 can only be used in Flex-Fuel Vehicles (FFVs) that are equipped with sensors capable of detecting the ethanol content and automatically adjusting fuel injection and ignition timing. E100 is essentially pure ethanol fuel, containing close to 100% ethanol. It ...