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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.

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This study aims to evaluate the status of Iranian gas industry and to formulate appropriate policies in order to attain the objectives of Iran’s Vision 2025. A dynamic model including exploration, production, consumption and demand sub-systems is designed based on the system dynamics approach and is simulated for the period 2010-2025. In this model, factors affecting natural gas exploration, demand and consumption as well as production, export and import of all other fuels in energy supply are identified and their dynamic interactions are investigated. The results of solving the basic model indicated that except for a 75 % share of gas consumption, none of Vision’s objectives would be attained, if current policies were followed. Accordingly, new policies are formulated and included in the model in the form of some scenarios. The results of simulating such scenarios suggest that other than coordinating the subdivisions of gas industry, production and exploration rates should be increased and significant technological exploration and production advances should be made in order to attain the objectives considered in the gas industry. Furthermore, clean energies such as water, wind and solar resources should be utilized increasingly in order to supply a part of domestic consumption. The results of model validation tests indicate the validity of the model as acceptable.