Investigating the environmental Kuznets curve hypothesis in seven regions: The role of renewable energy

The aim of this research is to investigate how renewable energy consumption effects pollution and whether the relationship between income and pollution formulates the inverted U-shaped relationship which signals the existence of the environmental Kuznets curve (EKC). To realize the aims of this study, non-stationary panel data techniques were utilized to examine the seven selected regions. According to Pedroni and Fisher type cointegration tests, the variables were cointegrated. Moreover, the dynamic ordinary least square (DOLS) and the vector error correction model Granger causality revealed that renewable energy consumption has a significant negative effect on pollution in Central and Eastern Europe, Western Europe, East Asia and the Pacific, South Asia, and the Americas. However, the tests revealed that renewable energy consumption has no significant effect on pollution in the Middle East and North Africa and Sub-Saharan Africa. In addition, the results in general indicated that the existence of the EKC hypothesis is determined by the significance of the renewable energy consumption. Therefore, the EKC hypothesis was only found in the regions where their renewable energy has a significant correlation with pollution in both the short run and the long run. Furthermore, a number of policy recommendations were provided for the investigated regions. (C) 2016 Elsevier Ltd. All rights reserved.