Measurement of Environmental Performance of Iranian Electric Power Companies (In the context of Contemporaneous and Sequential Frontiers of Slack-Based Measures and Directional Distance Functions)

Many countries are trying to reduce energy consumption and C emissions by increasing the efficiency and productivity of industries. Therefore studying of environmental efficiency is one of the most common and engaging issues in environment and energy economics. In this paper, we assess the environmental efficiency of Iranian electric power companies by two Data Envelopment Analysis approaches (that is Slack-Based Measures and Directional Distance Functions) in the period of 2004-2014. The results show that Isfahan, Kerman and Gilan electric power companies consist of a high efficiency group, while Sistan and Bluchestan and Kish Electric Power Companies exhibit low efficiency scores. Also, Azerbaijan, Isfahan Khuzestan and Mazandaran electric power companies have been technological regress in recent years. Generally, the overall performance of power industry has been faced with consecutive efficiency decrease and the highest technological regress since liberalization of energy prices in 2010. On the other hand, the Kruskal–Wallis statistic accepts the hypothesis that environmental performance of power industry has been affected by this liberalization.