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Increase in environmental pollutions of fossil fuels calls for policies stimulating clean technology deployment especially in the transportation sector. To evaluate the efficacy of these policies we should explore the preferences of consumers regarding different technologies. In this paper we use a discrete choice approach used in “Canadian Integrated Model system” (SIMS) to identify the behavioral components. This model has a hybrid top-down bottom-up structure. For this purpose we estimate a multi-nominal logit model (MNL) for different automobile technologies and different transportation modes based on preferences revealed by a sample of 250 Tehran citizens. Then, we evaluate the effects of economic, technological and environmental policies on market share of different automobile technologies and air pollution in Tehran. These policies include gasoline price increase, pollution tax, limitations on single passenger cars and limitations on use of gasoline driven cars. According to this analysis, technology based policies can effectively correct the market shares towards clean traffic technologies

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  Environmental Kuznets Curve ( EKC) theory has evolved over several decades from its initial intuitive conception to the complex theoretical models of today. Through successive steps of empirical and theoretical debate, a quadratic relationship between income and environmental degradation has been proposed, criticized, defended, and criticized again.

  Along the way, each finding have new look at the subject. Critic that is provided by Mazzanti et al. (2007) and Stern (1998) is that instead of attempting to gain insight into the underlying mechanics of an EKC theoretical foundation, there are undue focus on exploring empirical regularities among a large set of variables. These critics from opponent and supporter cause researcher to review their approach and take more concerns on details and methodology of EKC theory that make the way of theoretical works.

In this paper, a microeconomics model is provided in which household confront with decision about consumption of dirty and clean goods. It is showed that household make decision in the way that, as income increases, environment pollution rise at first and then fall when household substitute dirty goods by clean goods.

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    This study aims at determining the optimal environmental tax policy in the context of a dynamic model. For this purpose, clean technology diffusion was added to the AK growth model and the theoretical model has been generalized to the open economy. The main feature of the economy is creating pollution in the process of economic growth and its negative impact on social welfare. The diffusion of clean technology reduces pollution emission and has a positive effect on environmental quality and social welfare.

  The Hamiltonian solution of the model indicates that the steady state growth rate and optimal tax pollution is affected by the consumer preference toward consumption and environmental quality, pollution elasticity with respect to production, clean technology diffusion, foreign growth rate, inverse elasticity of intertemporal substitution , depreciation rate of capital and trade parameters.

  The results show that the optimal tax rate in Iranian economy is about 15 percent. Furthermore, sensitivity analysis shows that the emission elasticity of pollution subject to the production and environmental preference parameters have larger impacts on optimal tax rate than foreign growth rate and trade parameters.

 

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  The aim of this study is to calculate the marginal private and social costs of two thermal power plants in Isfahan region for a particular day in January 2010. For this purpose a nonlinear planning model with linear constraints has been used. The objective function (social cost) which is a twofold objective function is calculated by the summation of variable costs and external costs of power plants in the above mentioned region.

  The results of minimizing the objective function of private cost and also minimizing objective function of social cost indicate a significant difference between marginal social cost and marginal private cost. This difference is considered as marginal external cost in peak hours of electricity consumption and has had an obvious increase to the off-peak hours of electricity consumption in the region of the study. Taking into account the social costs of electricity generation, green power generation technologies can compete with thermal power plants.

 

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In this study, we designed and simulated a system dynamic model to analyze the impacts of energy intensity changes on environmental and economic indicators in Iran. Results show that if the current situation is continued, the industrial sector energy intensity will increase from 2.67 in the base year to 2.704 at the end of planning horizon. So, the sector will consume 540 million oil barrels to create a value added equals 490627 billion Rials in 2025. Accordingly, the amount of environmental pollutants will increase from 59 million tons in the first year to 267 million tons in 2025 and social costs of producing this pollution would be equal to 67, 449 billion Rials. These findings indicate that regarding the limitation of the production and the increasing costs of energy supply in the future, the country's industrial policies should concentrate on technological changes to increase the efficiency of energy consumption. Also, results indicate that industrial energy consumption has destructive effects on the environment and society in the future and the costs in this sector will not be reversible.