**Abstract**

Since the middle of 1970s, the enthusiasm for using alcohols as alternate convenient fuels in internal combustion engine (IC) has been increased and it has reached peak stage by the middle of 1980s. The usage of alcohol as an alternate fuel, due to its minimal undesired effects on atmosphere, has gained importance. Harmful effects on environment are caused by various fossil fuels and their exhaust emissions such as carbon monoxide, carbon dioxide, hydrocarbons, nitrogen oxides and particulate matter. Alcohol type of fuels is alternative to petroleum-based fuels due to reduced greenhouse gas emission, toxic exhaust emission and enhancement of overall energy efficiency. Moreover, they are convenient for internal combustion engines due to their high octane rating, burning velocities and wider flammability limits. In order to achieve better environmental sustainability, it is the right time to use lower molecular weight alcohols (alcohols possessing lower molecular weight, such as methanol, ethanol) replacing other additives as octane boosters in automotive fuels in the present situation.

**Keywords:** methanol, ethanol, alcohol fuel, sustainable development, environment
