Asgar khademvatani - Faculty member at the Petroleum University of Technology
Abdolsalam Ebrahimpour - M.A. in Oil and Gas Economics from the Petroleum University of Technology

This paper investigates the causal relationships between CO2 emissions, industrial value added, renewable and non-renewable energy consumption, and trade for selected OPEC member countries over the period 1990–2014. Our short-run Granger causality tests for export model show a unidirectional causality running from non-renewable to renewables and also from industrial productions to exports. Furthermore, there are a bidirectional causal relationships between industrial productions with CO2 emissions and non-renewable energy consumption. When imports is included in the model, we have a unidirectional causality from CO2 to industrial productions. Also, a bidirectional causality between CO2 emissions and industrial productions exist. In the long-run, the error correction terms estimated are statistically significant for all estimated equations except when exports and imports are dependent variable. Our long-run fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) estimates show that the inverted U-shaped environmental Kuznets curve (EKC) hypothesis is verified for this sample of OPEC countries in the model with exports and also in the model with imports variable. According to the results, more trade and more use of renewable energy are efficient strategies to combat global warming in these countries.

Environmental Kuznets curve, Renewable energy, Non-renewable energy, Trade, OPEC