Ethanol blending is the practice of blending petrol with ethanol.
Many countries, including India, have adopted ethanol blending in petrol in order to reduce vehicle exhaust emissions and also to reduce the import burden on account of crude petroleum from which petrol is produced.
The renewable ethanol content, which is a byproduct of the sugar industry, is expected to result in a net reduction in the emission of carbon dioxide, carbon monoxide (CO) and hydrocarbons (HC).
Ethanol itself burns cleaner and burns more completely than petrol it is blended into.
In India, ethanol is mainly derived by sugarcane molasses, which is a by-product in the conversion of sugar cane juice to sugar.