Investigation on Social Benefits of Substitution of Gasoline with CNG in Tehran's Taxis

Environmental pollution in metropolitans due to rapid growth of using gasoline as the main fuel in transportation sector has become one of the most important problem in national level, so substituting clean fuels in this sector could be one of the most effective options.The main question which this research is going to answer is the beneficiary (non-beneficiary) of converting Tehran's taxis from gasoline to Compressed Natural Gas (CNG) in order to decrease social costs that should be interpreted as increasing social benefit's factor. In this article, after reviewing the current concepts and principles of social costs and their measuring methods, social benefits of substituting gasoline with CNG are evaluated. Considering the existing figures, reduced social costs as a result of this substitution are calculated.The results of this research suggests that substituting gasoline with CNG in Tehran's taxis reduces the social costs of using gasoline (about 63.8 Million US $). As a matter of fact this substitution increases the social benefits equivalent at mentioned figure.